Obesity in primary school children in Accra Metropolis This dissertation is submitted to the School of Public Health, University of Ghana, Legon in partial fulfillment of the requirement for the award of Master of Public Health Degree By Svitlana Aduama September 2004 University of Ghana http://ugspace.ug.edu.gh <2574970 'g.33cl1'C€ t^1 U l. ^ c c ' [ University of Ghana http://ugspace.ug.edu.gh Declaration. I do hereby declare that except for duly acknowledged citation and ideas, this dissertation is an original work produced by me from a study personally under+ J .en and was not submitted for any degree elsewhere. Signed^ % Academic Supervisors: Prof. A.G.B. Amoah Signed Dr. L. Ahadzie Signed_ University of Ghana http://ugspace.ug.edu.gh Abstract Objectives: To determine the prevalence and socio-demographic aspects o f obesity in primary school children in Accra Metropolis. Design: A descriptive cross-sectional survey was conducted on sample o f 1123 children aged 6-10 years attending primary schools who were selected by multistage sampling using school registers and listings o f primary schools by Accra Metropolitan Education Service. Setting: Four public and four private primary schools in Accra Metropolis. Subjects and Methods: In total, 1123 subjects (584 females and 539 males) participated. There was however 912 questionnaires available for further analysis. Socio-demographic data were obtained by self-administered questionnaire and measurements were made o f weight, height and triceps skin fold thickness. Results: The mean age for males was 8.43 years and that for females 8.41years (p<0.001).The mean weight for males was 26.8kg and that for females 27.8kg (p<0.001). The mean BMI for males was 16. lkg/m2 and that for females 16.5kg/m2 (p<0.001). The mean skin fold thickness for males was 6.8mm and that for females 9.6mm (p<0.001). Crude prevalence o f obesity (above 95 percentile) was 5% (by CDC- criteria 3.4%), prevalence o f risk o f overweight (above 85 and below 95 percenlile) was 10.2% (by CDC criteria 7%) and prevalence o f underweight (below 5 percentile) was 4.8% (by CDC criteria 3.7%). The crude prevalence o f obesity by skin fold thickness distribution was 5.3%. The rates o f obesity (7% vs2.8%) and at risk o f overweight (12.3% vs 7.8%) were higher in females than males. There were more obese and at risk o f overweight subjects in University of Ghana http://ugspace.ug.edu.gh the private schools 9.6% and 14.1% than that in public schools 1.1% and 6.8%, respectively. Obesity and risk o f overweight were highest among Akan and Ewe tribes. Subjects o f parents with tertiary education were more obese and at risk o f overweight than their counterparts o f parents with lower educational level. Conclusion: Obesity does not yet appear to be a major problem in primary school children in Accra. A significant number, a tenth o f the children, were at risk o f overweight category. There was co- existence o f obesity and underweight Economic status appeared to be an important determinant o f nutritional status. Female gender, Akan ethnical group, private schools and higher school fees, tertiary education o f the parents were associated w ith higher levels o f obesity and overweight. Further work is needed to ascertain the real reasons for observed differences. University of Ghana http://ugspace.ug.edu.gh Acknowledgement T am greatly indebted to my academic supervisors Professor A.G.B. Amoah and Dr. L. Ahadzie for their guidance and support as well as the useful discussions held throughout the entire study. I am grateful to the lecturers o f the School o f Public Health for development research skills and for their guidance through the development o f the study. I acknowledge the support given by the D irector o f Education Accra Metropolis Mr. A.B. Amoatey, Headmasters/mistresses and teachers for their assistance in conducting the research. I am grateful for support given by the National Diabetes Management and Research Centre through provision o f equipment needed for the study. 1 owe a debt o f gr atitude to the National Surveillance Unit team for their immense support in providing guidance, especially in Epi Info training, encouragement and logistics needed for the study. I wish to express my gratitude to all research assistants who worked tirelessly and helped generate quality information. I appreciate the contributions made by my colleagues and friends. I can not leave out the children and their parents who participated in the study. Finally, I wish to express my profound gratitude to my family members for their understanding and support while I undertook this study. University of Ghana http://ugspace.ug.edu.gh AMA Accra Metropolitan Area BIA Bioelectrical Impedance BMI Body Mass Index 0 Cedi (Ghanaian currency) CAT Computerized Axial Tomography CDC Centers for Diseases Control Cl Confidence Interval DEXA Dual Energy X-ray Absoptiometry IOTF International Obesity Task Force MRI Magnetic Resonance Imaging NAFLD Non-alcoholic fatty liver disease NASH Non-alcoholic steatohepatitis NHANES National Health and Nutrition Examination Survey NCHS National Centre for Health Statistics USA SD Standard Deviation St Sent WHO World Health Organization WHR Waist-to-Hip Ratio WHZ Weight for Height Z-score List of abbreviations. v University of Ghana http://ugspace.ug.edu.gh Table of Contents 1.0 Introduction and background 1.1 Background Information........................................................................... 1 1.2 Statement o f the Problem ...........................................................................2 1.3 Rationale for Study......................................................................................3 1.4 Study Site...................................................................................................... 4 1.5 Study Objectives..........................................................................................4 2.0 Literature Review 2.1 Introduction....................................................................................... .............5 2.2 Assessment o f obesity: which child is fat?..............................................6 2.3 Global secular trends and prevalence o f obesity in children and Adolescents...................................................................................................14 2.4 Prevalence o f overweight in Sub-Saharan Africa.............................. 18 2.5 The physical and psycho-social consequences o f childhood obesity.. 18 2.6 Population groups at higher risk for obesity...........................................22 2.7 Environmental risk factors............................. ................. ........................... 24 2.8 Prevention- the only solution.....................................................................25 3.0 Methodology and Materials 3.1 Study Design................................................................................................. 27 3.2 Variables........................................................................................................ 27 3.3 Sampling Method........................................ ................................................. 27 3.4 Sample Size Determination......................................................................... 29 3.5 Eligibility criteria...........................................................................................29 3.6 Training and pre-testing .....................................................................30 3.7 Ethical Considerations...................................................................................31 3.8 Data Collection, Management and Analysis.............................................32 3.9 Limitations o f the study.................................................................................34 University of Ghana http://ugspace.ug.edu.gh 4.0 Results...........................................................................................................................35 5.0 Discussion..................................................................................................................... 58 6.0 Conclusion and Recommendations...................................................................... 61 References..........................................................................................................................63 Appendices. 1. Questionnaire on socio-economic status o f the primaiy school children..........72 2. Informed Consent form ................................ 74 3. International cut-off points for BMI for overweight and obesity by gender from 2 to 18 years........................................................................................................................ 75 vii University of Ghana http://ugspace.ug.edu.gh 1. Characteristics o f participated schools....................................................................35 2. Mean value ± SD o f selected variables o f the study population........................ 36 3. Distribution n (%) o f ethnic groups by age and gender....................................... 40 4. Distribution o f means ± SD o f selected variables and obesity prevalence by schools...........................................................................................................................48 5. Distribution o f BMI categories by gender and type o f the school by CDC criteria......................................................................... . . . . . ................................. 51 6. Distribution o f BMI categories by school fees category..................................... 51 7. Distribution o f BMI categories by ethnic affiliation............................................. 52 8. Distribution o f BMI categories by level o f father’s education...........................52 9. Distribution o f BMI categories by level o f mother’s education........................ 53 10. Distribution o f BMI categories by possession o f a house and cooker............54 11. Agreement between BMI and skin fold thickness in diagnosing obesity 54 12. Correlation between age, BMI and skin fold thickness..................................... 55 13. Partial Correlation between weight, height, BMI and skin fold thickness controlling for age..................... 56 14. Partial Correlation between weight, height, BMI and skin fold thickness controlling for gender............................................................................................. 57 List of Tables. University of Ghana http://ugspace.ug.edu.gh 1. Gender distribution by Age.................................................................................. 37 2. Distribution o f mean BMI by Gender and Age.................................................37 3. Mean skin fold distribution by Gender and Age..............................................38 4. Ethnic distribution by age......................................................................................39 5. Weight for Age for all females............................................................................ 41 6. Weight for Age for all m ales................................. 42 7. BMI for Age for all females....................................................................................43 8. BMI for Age for all m ales....................................................................................... 44 9. Nutritional Status of Primary school children in Accra..............................45 10. Distribution o f BMI categories by Gender......................................................... 46 11. D istributioi o f BMI categories by Gender by CDC criteria.......................... 46 12. Distribution o f BMI categories by Age in girls..................................................47 13. Distribution o f BMI categories by Age in boys..................... ....................... 47 14. Distribution o f BMI categories by type o f school.............................................49 15. Distribution o f BMI categories by type o f school by CDC criteria............... 50 List of Figures. University of Ghana http://ugspace.ug.edu.gh 1.0 Introduction. 1.1 Background Information The prevalence o f overweight and obesity is increasing worldwide at an alarming rate in developed and developing countries1' 4' 57. Obesity may be defined as a condition in which there is an excessive amount o f body fat. Obesity is a disease o f complex and multiple causes leading to an imbalance between energy intake and output and to the accumulation o f large amounts o f body fat. It is measured most often as excessive weight for a given height, using the body mass index (BMI)— weight in kilograms (kg) over height squared (m2). The World Health Organization (WHO) defines overweight as a BMI from 25.0 to 29.9 kg/m2 and obesity as a BMI o f 30.0 kg/m2 or greater1. Excess body weight is associated with increased risk for cardiovascular disorders5, type 2 diabetes6, dislipidaemia5’6, endocrine disorders58, osteoarthritis, some cancers and gallbladder disease59'60. Obesity rates, which are doubling every 5-10 years in many parts o f the world, are placing significant additional financial burdens on health systems. Many developing nations are undergoing epidemiological transition with alterations in diet and physical activity61. Some countries with high levels o f obesity also report significant rates o f child-hood stunting and nutritional deficiencies62. Maintaining a. dual nutrition agenda, preventing obesity and related chronic diseases while eliminating nutritional deficiencies, presents a difficult challenge to countries with limited resources. Childhood obesity is a problem because it is an important predictor o f adult obesity63. About one third o f obese preschool children become obese adults, and 1 University of Ghana http://ugspace.ug.edu.gh one-half o f obese school-age children become obese adults. Childhood obesity, just like adult obesity, is caused by an imbalance between calories-in and calories- out. But this simple equation is confounded by complex social facts that influence how children eat, exercise, and play. 1.2 Problem statement WHO defined obesity as a condition where fat has accumulated to such extent that health is adversely affected. Ten percent o f the world’s school-age children are estimated to be carrying excess body fat, an increased risk for developing chronic diseases. Childhood obesity is an important predictor o f adulthood obesity A number o f developing countries undergoing rapid socio-economic and nutrition transitions are experiencing shift from under- to over nutrition problems. Their fragile health systems may face a double burden o f malnutrition and obesity. In industrialized countries it is children in lower socioeconomic groups who are at a greater risk. In contrast, developing countries show obesity to be more prevalent among higher income sectors o f the population, and among urban populations rather than rural ones. An assessment o f the local information on nutritional status o f school age children identified the following: data are scanty, scattered and not nationally representative. In the past nutritional data was collected mostly in children under 5 years and focused on malnutrition and food security. In the face o f increasing trends o f overweight and obesity reliable baseline data on childhood obesity would be useful. Therefore, the research questions o f this study were: What was the level o f obesity in primary school 2 University of Ghana http://ugspace.ug.edu.gh children in Accra metropolis, most urbanized area in the country? Were there any differences in obesity prevalence among private and public schools? 1,3 Rationale for study In 1995, estimated 17.6mln children in the low income countries were overweight.68 An understanding and awareness o f the burden o f nutritional problems among school-age children is growing although until recently there have been few surveys that document nutritional status o f school-age children in Ghana. Nationally representative data are lacking. Furthermore, there are methodological concerns, the use and interpretation o f weight for height indices based on children from USA has been questioned in populations w ith significant level o f stunting. Prevention o f obesity in developing countries is imperative, since improvements in socioeconomic conditions and rapid urbanization are causing a ‘nutrition transition’. The recent study among adults in Accra revealed prevalence o f overweight and obesity was 23.4 and 14.1% respectively.64 Countries undergoing a ‘nutrition transition’ have high levels o f stunting (low height-for-age), which is believed to be a risk factor for obesity. For this reason, we should look towards prevention efforts for children, rather than focusing solely on treating the obesity that already exists. Comprehensive strategies that consider both physical activity and nutrition in home, school, and community settings are needed for remedial actions to be effective. To monitor such interventions, reliable baseline data on childhood obesity would be useful. Such data are presently not available or difficult to find. 3 University of Ghana http://ugspace.ug.edu.gh 1.4 Study site The capital Accra is the most urbanized and densely populated area in the country, with an urban population o f 1.6 million (2000 Census). For administrative purposes it is divided into 6 sub-metros: Ablekuma, Ayawaso, Ashiedu-Keteke, Kpeshie, Okaikoi and Osu-Clottey. Pre-Adolescent population (5-9 years) comprises 14.67% (2000 Census). There are 386 public and number o f private primary schools in Accra. Current primary school attendance in Greater Accra region is 361080 pupils (2000 Census). 1.5 Study Objectives. Main Objective of the study. To estimate the prevalence o f obesity/ overweight and underweight among children (aged 6-10 years) attending primary schools (public and private) in the Accra Metropolitan area (AMA). Specific objectives. • To measure weight, height and triceps skin fold o f children. • To calculate Body Mass Index (BMI) for every participant. • To evaluate distribution o f mean BMI and skin fold thickness among children by age and sex. • To estimate proportion o f obese, at risk o f overweight and underweight children.. • To determine the demographic and socioeconomic associations o f obesity. • To analyze significance o f skin fold thickness as an indicator for obesity. 4 University of Ghana http://ugspace.ug.edu.gh 2.0 Literature review. The success o f child survival programs and expansion o f basic education coverage have resulted in a greater number o f children reaching school age with a higher proportion actually attending primary school.(10) The main nutritional problems facing the school-age child include stunting, underweight, anaemia and iodine and vitamin A deficiencies. In countries experiencing the “nutrition transition, overweight and obesity are increasing problems in school-age ch ild (2) Ten per cent o f the world’s school-age children are estimated to be carrying excess body fat(Figure. 1), an increased risk for developing chronic diseases5’6,60. F igure 1. Prevalence o f overweight and obesity among school-age children in global regions. Overweight and obesity defined by International Obesity Task 35 H overweight O obese - > 5 University of Ghana http://ugspace.ug.edu.gh Force (IOTF) criteria. Children aged 5 -17 years. Based on surveys in different years after 1990. Source: IOTF (3)' Obesity is associated with several risk factors for later heart disease and other chronic diseases including hyperlipidaemia, hyperinsulinaemia, hypertension, and early atherosclerosis.4'6 The burden o f obesity upon the health services cannot yet be estimated. Although childhood obesity brings a number o f additional problems in its train - hyperinsulinaemia, poor glucose tolerance and a raised risk o f type 2 diabetes, hypertension, sleep apnoea, social exclusion and depression- the greatest health problems will be seen in the next generation o f adults as the present childhood obesity epidemic passes through to adulthood. Greatly increased rates o f heart disease, diabetes, certain cancers, gall bladder disease, osteoarthritis, endocrine disorders and other obesity related conditions will be found in young adult populations, and their need for medical treatment may last for their remaining life-times. For example, 10% o f young people with type 2 diabetes are likely to develop renal failure by the time they enter adulthood, requiring hospitalization followed by life-long dialysis treatment.7 Health services, especially in developing countries, may not easily bear these cost, and the result could be a significant fall in life expectancy. 2.1 Assessment o f obesity: which child is fat? Power et al. suggest that ‘an ideal measure o f body fat should be accurate in its estimate o f body fat; precise, with small measurement error; accessible, in terms 6 University of Ghana http://ugspace.ug.edu.gh o f simplicity, cost and ease o f use; acceptable to the subject; and well documented, with published reference values’ 8 They further comment that ‘no existing measure satisfies all these criteria. Measurement of adiposity in children and adolescents occurs in a range of settings, using a range of direct and indirect methods. Direct measures o f body composition provide an estimation o f total body fat mass and various components o f fat-free mass. Such techniques include underwater weighing, magnetic resonance imaging (MRI), bioelectrical impedance analysis (BIA), computerized axial tomography (CT or CAT) and dual energy X-ray absorptiometry (DEXA). These methods are used predominantly for research and in tertiary care settings, but may be used as a ‘gold standard’ to validate anthropometric measures o f body fatness8. Among the anthropometric measures o f relative adiposity or fatness are waist, hip and other girth measurements, skin fold thickness and indices derived from measured height and weight such as Quetelet’s index (BMI or W H '2), the ponderal index (W H '3) and similar formulae. All anthropometric measurements rely to some extent on the skill o f the measurer, and their relative accuracy as a measure o f adiposity must be validated against a ‘gold standard’ measure o f adiposity. Procedure: W eight and w eight-for-height Description: Total body weight can be recorded and compared with reference standards based on a child’s age. Low weight-for-age is a widely used marker o f malnutrition for younger children. However, weight is correlated with height, and reference 7 University of Ghana http://ugspace.ug.edu.gh standards based on weight-for-height provide a more accurate measure ol under- or overweight, and take account o f possible confounding from inadequate linear growth (stunting) when assessing nutritional status. Validation: Growth charts are based on standard reference populations (usually the US National Center for Health Statistics reference population) Weight-for-height charts are inaccurate beyond the age o f around 10-11 years and the measure is not useful in older children and adolescents 9 Comments: Weight and height (or length) is relatively easy to obtain, although they tend to be more accurate if taken by a trained person. Procedure: Body mass index (B M I) Description: BMI is defined as weight (kg) /height squared (m2), and is widely used as an index o f relative adiposity among children, adolescents and adults. Among adults, the WHO recommends that a person with a BMI o f 25 kg m '2 or above is classified overweight, while one with a BMI 30 kg m"2 or above is classified obese 1 For children, various cut-off criteria have been proposed based on reference populations and different statistical approaches. Validation: 8 University of Ghana http://ugspace.ug.edu.gh BMI has been compared with dual-energy X-ray absorptiometry (DEXA) in children and adolescents aged 4-20 years 11 BMI had a true positive rate of 0.67, and a false positive rate of 0.06 for predicting a high percentage o f total body fat. Sardinia) el al. 12 reported a true positive rate o f 0.83 for 10-11 year olds, 0,67 for 12-13 year olds and 0.77 for 14-15 year olds, while the false positive rate ranged from 0.03 in 12-13 year olds to 0.13 in 10-11 year olds. Therefore, although some overweight children would be wrongly classified as being o f normal weight when using BMI as a screening test, few children would be classified as overweight if they were not. Comments: BMI is more accurate when height and weight are measured by a trained person rather than self-reported. Measurement o f height and weight has a high subject acceptance, which is particularly important for adolescents who may be reluctant to undress (measures are normally taken in light clothing, without shoes). There is low observer error, low measurement error and good reliability and validity. Hence two people with the same amount o f body fat can have quite different BMIs 12 There may also be racial differences in the relationship between the true proportion o f body fat and B M I14 Procedure: W aist circum ference and W aist-to-hip ra tio (WHR) Description: Waist circumference is an indirect measure o f central adiposity. Central adiposity is strongly correlated with risk for cardiovascular disease in adults and an 9 University of Ghana http://ugspace.ug.edu.gh adverse lipid profile, hyperinsulinaemia in children 13 Waist circumference is measured at the minimum circumference between the iliac crest and the rib cage using a flexible tape measure. W-to-hip ratio has been used among adults to identify people with high central adiposity. Validation: In young people aged 3-19 years, the correlation between waist circumference and DEXA o f trunk fat were 0.83 for girls and 0.84 for boys Waist-to-hip ratios are less well correlated with trunk fat measures using DEXA 16 Comments: Waist and hip circumferences are easy to measure with simple, low-cost equipment, have low observer error, offer good reliability, validity and low measurement error. However, there are no accepted cutoff values for the classification o f overweight and obesity based on these measures, and there have been few studies o f the relation between central adiposity and the metabolic disturbances associated with excess visceral fat among children and adolescents. Procedure: Skin fold thickness Description: Skin-fold thickness can be measured at different sites on the body (e.g. triceps, sub scapular) using skin-fold calipers. Prediction equations can then be used to estimate fat mass and percentage fat from the skin-fold measurements. Validation: Children’s abdominal skin-fold thickness correlates well (r = 0.88) with visceral 10 University of Ghana http://ugspace.ug.edu.gh adipose tissue as measured by CT scan or M R I1'. Triceps skin-fold thickness shows a sensitivity o f 0.79 in 10-11 year olds, 0.78 in 12-13 year olds and 0.87 in 14-15 year olds when compared with DEXA in measuring obesity (=30% body fat) 12 Comments: Skin-fold thickness uses simple equipment and offers only a moderate respondent burden, and has the potential to determine total body fat and regional fat distribution. However, skin-fold thickness varies with age, sex and race, and the equations relating skin-fold thickness at several sites to total body fat need to be validated for each population. Measurement requires training and intra- and inter-observer reliability is poor 18 In very obese individuals the measurement o f triceps skin-fold or other skin-fold thicknesses may not be possible. The relationship with metabolic problems is unclear. Definitions of ‘overw eight’ and ‘obesity’ in young people The primary purposes for defining overweight and obesity are to predict health risks and to provide comparisons between populations. Faced with a continuous distribution, criteria need to be created that define where cut-off points should occur that best fulfill these purposes. For practical reasons, the definitions have usually been based on anthropometry, with waist circumference and BMI being the most widely used both clinically and in population studies. 11 University of Ghana http://ugspace.ug.edu.gh As suggested in Table 1 above, BMI is significantly associated with relative fatness in childhood and adolescence, and is the most convenient way o f measuring relative adiposity i9. BMI for age reference charts and BMI for age percentiles. BMI varies with age and gender. It typically rises during the first months after birth, falls after the first year and rises again around the sixth year o f life: this second rise is sometimes referred to as ‘the adiposity rebound’23. A given value o f BMI therefore needs to be evaluated against age- and gender-specific reference values. Several countries, including France, the UK, Singapore, Sweden, Denmark and the Netherlands, have developed their own BMI-for-age gender- specific reference charts using local data. In the USA, reference values published by Must et al. 20 derived from US survey data in the early 1970s, have been widely used and were recommended for older children (aged 9 years or more) by a WHO expert committee in 1995 21. More recently, the US National Center for Health Statistics (NCHS) has produced reference charts based on data from five national health examinations from 1963-1994 22, although to avoid an upward shift o f the weight and BMI curves, data from the most recent survey were excluded for children over the age o f six years 23. The NCHS documentation 22recommends that those children with a BMI greater than or equal to the 95th percentile be classified as ‘overweight’ and those children with a BMI between the 85 th and 95th percentile be classified as ‘at risk o f overweight’. In some papers, US children at or above the 95th centile are referred to as ‘obese’ 24 and in others ‘obesity’ refers to US children above the 85* centile 23. 12 University of Ghana http://ugspace.ug.edu.gh BMI for age Z-scores. As with the use o f weight-for-height measures compared with standard reference populations, BMI can be compared with a reference data set and reported as Z-scores. A BMI Z-score is calculated as follows65: fObserved value) - (median reference value o f a population) Standard deviation o f reference population A Z-score o f 0 is equivalent to the median or 50th centile value, a Z-score o f +1.00 is approximately equivalent to the 84th centile, a Z-score o f +2.00 is approximately equivalent to the 98th centile and a Z-score o f +2.85 is >99* centile. As with other measures, BMI Z-scores can be used to compare an individual or specified population against a reference population. BMI for age Z- scores, however, require suitable statistical skills or software programmes. Also Z-scores are associated with difficulty in choosing an appropriate reference population, and there are only arbitrary cut-off points for categorizing into non­ overweight, overweight and obese. BMI based on adult cut-off points. An expert committee convened by the International Obesity Task Force in 1999 determined that although BMI was not ideal as a measure o f adiposity, it had been validated against other, more direct measures o f body fatness and may therefore be used to define overweight and obesity in children and adolescents19. As it is not clear at which BMI level adverse health risk factors increase in children, the group recommended cutoffs based on age specific values that project to the adult cut-offs o f 25 kg m'2 for overweight and 30 kg m '2 for obesity. Using data from six different reference populations (Great Britain, Brazil, the Netherlands, Hong Kong, Singapore and the USA) Cole et al. 23 derived centile curves that passed 13 University of Ghana http://ugspace.ug.edu.gh through the points o f 25 kg m"2 and 30 kg m '2 at age 18 years. These provide age and gender specific BMI cut offs to define overweight and obesity, corresponding to the adult cut o ff points for overweight and obesity. The tables developed by Cole et a l (reproduced in Appendix 1) are useful for epidemiological research in that children and adolescents can be categorized as non-overweight, overweight or obese using a single standard tool. The cutoff points were developed using several data sets, therefore they represent an international reference that can be used to compare populations world-wide. The authors, however, acknowledge that the reference data set may not adequately represent non-Westem populations. 2.2 Global secular trends and prevalence o f obesity in children and adolescents Representative data for examining the problem o f childhood obesity have been collected in many industrialized countries, especially in North America and Europe as well as in a number o f developing countries, although for most developing countries the data are more limited, especially data on older children (>5 years) and adolescents. Nevertheless, data collected in national and local surveys from different parts o f the world provide useful insights into the global obesity situation among young people (Figure 2) (i) Global prevalence is unequally distributed Taken overall, the data available from surveys o f young people aged 5-17 years, collated for the WHO Global Burden o f D isease report and extrapolated to countries where no data are available, indicates the prevalence o f overweight 14 University of Ghana http://ugspace.ug.edu.gh (including obesity) to be approximately 10% in this age range, and the prevalence o f obesity to be 2-3% This global average reflects a wide range o f prevalence levels, with the prevalence o f overweight in Africa and Asia averaging well below 10% and in the Americas and Europe above 20 %.3 (ii) Childhood overweight is rising rapidly The prevalence o f excess weight among children is increasing in both developed and developing countries, but at very different speeds and in different patterns. North America and some European countries have the highest prevalence levels, and have shown high year-on-year increases in prevalence. (Hi) Overweight is high among the poor in rich countries, and the rich in poorer countries In industrialized countries it is children in lower socioeconomic groups who are at greatest risk. In contrast, developing countries show obesity to be more prevalent 15 University of Ghana http://ugspace.ug.edu.gh Algeria Egypt Argentina Chile Morocco South Africa Bolivia Peru Uruguay Jamaica Jordan Australia D.-inil USA China Zimbabwe indonesia Paraguay Azerbaijan Kenya Iran Pakistan Venezuela Turkey Uganda Colombia Tanzania Romania Ghana India Mali Bangladesh Central Afric Philippines Vietnam 0 1 2 3 4 5 6 7 8 9 10 Percentage Figure 2. Prevalence o f obesity among children aged under 5 years. Obesity in under fives according to WHO standardized cut-offs (Z > 2.0). Based on surveys in different years. Source: de Onis & Blossner 26 among higher income sectors o f the population, and among urban populations rathei than rural ones (Figures3, 4). 16 University of Ghana http://ugspace.ug.edu.gh F igu re 3. Prevalence o f overweight according to residential area. Overweight defined by IOTF criteria. Survey years 1988-1994 (USA) and 1997 (Brazil, China). Children aged 6-18 years. Source: Wang et al.21 3 0 - 25 ■ d* » 20-0 J 1 5 - 1 10- 5 - 0- Figure 4. Prevalence o f overweight according to family income levels. Overweight defined by IOTF criteria. Survey years 1988-1994 (USA) and 1997 (Brazil, China). Children aged 6 -18 years. Source: Wang et al.1 35 30 25a o> 0 20 ca> 1 is »- o. 10 s 0 USA cm na Brazil A number o f developing countries undergoing rapid socio-economic and nutrition transitions are experiencing shift from under- to over-nutrition problems, and may experience a double burden o f malnutrition and obesity. For example, in Brazil between 1974 and 1997, the prevalence o f overweight and obesity (IOTF definitions) among young people aged 6-17 years more than tripled increasing from 4.1% to 13.9%), while the prevalence o f underweight (<5th centile NHANES-I) decreased from 14.8% to8.6%(27). It is likely that many other developing countries will show similar trends as economic conditions develop. USA China Brazil 17 University of Ghana http://ugspace.ug.edu.gh 2.3 Prevalence of overweight in Sub-Saharan A frica. There are very limited representative data available from African countries for studying the secular trends in childhood obesity, because most public health- and nutrition-related efforts have been focused on malnutrition and food safety problems. Most o f the available data that do exist are collected for pre-school children and focus on malnutrition. In general, the prevalence o f childhood obesity remains very low in this region, except for countries such as South Africa where obesity has become prevalent in adults, particularly among women, and where childhood obesity is also rising. According to a recent comprehensive study conducted among pre-school children from 24 sub-Saharan countries excluding South A frica2S, the prevalence o f overweight including obesity (defined as a weight-for-height standardized score greater than one, i.e. WHZ > 1 ) was below 10% in 18 countries, and the prevalence o f obesity alone (defined as WHZ > 2) was below 5% in all countries except one (Malawi). Overall, the prevalence o f overweight (including obesity) was 8.4% while for obesity alone the prevalence wasl.9% . 2.4 The physical and psycho-social consequences of childhood obesity. Physical health. Clinical studies o f obese children have suggested a range o f medical conditions for which obese children are at greater risk29 1.1. Sleep-disordered breathing and asthma 18 University of Ghana http://ugspace.ug.edu.gh A well-established pulmonary consequence o f childhood obesity is ‘sleep- associated breathing disorder’, most clearly seen in severe obesity. The term refers to a broad spectrum o f sleep-related conditions including increased resistance to airflow through the upper airway, heavy snoring, reduction in airflow (hypopnoea) and cessation o f breathing (apnoea). Obesity-linked hypoventilation syndrome, sometimes referred to as Pickwickian syndrome, is a serious condition associated with pulmonary embolism and sudden death in children30. 1.2. Fatty liver disease Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized as a major health burden in obese children, NAFLD is a spectrum, ranging from fatty infiltration o f the liver alone (steatosis) that is relatively benign to fatty infiltration with inflammation known as steatohepatitis or nonalcoholic steatohepatitis (NASH) and characterized by the potential to progress to fibrosis, cirrhosis and end-stage liver disease 31 Current prevalence estimates indicate that NAFLD affects approximately 3% o f all children in various countries and from 23% to 53% o f children who are obese, with up to 70% o f these having steatohepatitis, severe fibrosis or c irrhosis32. NAFLD therefore appears to be a common form o f liver disease in many children, especially in developed countries where the obesity epidemic is most advanced. 1.3. Menstrual problems and early menarche Abnormalities in menstruation and early menarche represent part o f the endocrine response to excess body weight in girls. Previous studies have established a 19 University of Ghana http://ugspace.ug.edu.gh relationship between obesity and lowered fertility33 but the impact o f excess weight on menstrual problems in adolescence is less well established. Oligomenorrhoea or amenorrhoea associated with obesity, insulin resistance, hirsutism, acne and acanthosis nigricans comprise a ‘polycystic ovary syndrome’. The appearance o f insulin resistance in youth, associated with overweight, may foreshadow an increased prevalence o f polycystic ovary syndrome in adolescence. Menarcheal timing is influenced by weight status, w ith higher relative weights associated with earlier m enarche34. The rise in childhood obesity seen in the last decade among younger children may result in a further lowering o f the population average age o f menarche. 1.4. Delayed maturation linked to obesity in adolescent boys Overweight boys tend to show later maturation than their non-overweight counterparts. Although early sexual maturity is associated with overweight in girls, in boys the reverse appears to be the case, with the prevalence o f overweight and obesity higher in late maturers than in early m aturers35. The differences are also reflected in the changing body composition that occur during puberty, when girls tend to increase fat mass as a result o f maturation while boys tend to increase muscle and other non-fat body mass. 1.5. Type 2 diabetes Previously only seen in adults, the emergence o f type 2 diabetes in youth represents a particularly alarming consequence o f the obesity epidemic in children. The onset of diabetes in youth will increase the risk in early adulthood of the advanced complications o f the disorder - cardiovascular disease, kidney 20 University of Ghana http://ugspace.ug.edu.gh failure, visual impairment and limb amputations. A review by the American Diabetes Association suggests that as many as 45% o f paediatric diabetes cases are the type 2 non-insulin dependent fo rm 36. Although other factors are associated with type 2 diabetes in children (including family history, ethnicity and the presence o f acanthosis nigricans), the most important risk factor is obesity. In a study o f childhood diabetes carried out in Arkansas (USA), Scott et al. j7 found excess bodyweight among over 90% o f adolescents with type 2 diabetes while among children with type 1 diabetes excess bodyweight was found in about 25% o f cases. 1.6. Cardiovascular risk factors The Bogalusa study in Louisiana (USA) has provided detailed information on cardiovascular risk factors in childhood and their persistence into adulthood38. In the study, overweight during adolescence was associated with an 8.5-fold increase in hypertension, a 2.4- fold increase in the prevalence o f high total serum cholesterol values, a 3-fold increase in high LDL serum cholesterol values and an 8-fold increase in low HDL serum cholesterol levels as adults aged 27-31 years39. Several studies have shown links between weight gain in childhood and a subsequent increase in cardiovascular risk factors in urban African-Americans 40 and in populations in Finland 41 The Finnish data suggest that the cluster o f cardiovascular risk factors in adulthood - including hypertension, hypertriglyceridaemia, low HDL cholesterol and hyperinsulinaemia - sometimes referred to as the metabolic syndrome, is especially common among obese adults who .'/ere also obese as children. 21 University of Ghana http://ugspace.ug.edu.gh Psychological and social consequences Obesity in children and adolescents may have its most immediate consequences in the psychological and social realms. Stigmatization o f obese children and adolescents has long been recognized in Westernized cultures, and is well documented among the children’s peers. Several studies found that obese children have greater social problems (peer rejection or stigma) or psychological problems (anxiety, depression or low self-esteem) than their non-obese peers. Not all cultures view excess weight as a negative attribute. For example, a study in Mexico noted that food treats’ for children are a cultural index o f parental caring, and that parents value child fatness as a sign o f health42. Ghanaians generally associate fatness with beauty in women and success in both sexes64. 2.5 Population groups at higher risk for obesity There are identifiable risk factors within the population o f normal children that increase their risk o f becoming obese. Ethnicity. It is a common impression that schoolchildren from non-Caucasian backgrounds living in Westernized societies have greater propensity for developing obesity than white Caucasian children, but when socio-economic *» circumstances and parental education are taken into account, the differences may not be great. In the USA, for example, African-Americans and H ispanic- Americans appear to contribute more to the obesity epidemic, with more rapid rates o f change in their populations, than does the white American population 43. 22 University of Ghana http://ugspace.ug.edu.gh Paren ta l obesity. The risk o f a child becoming overweight increases with parental overweight and obesity25. It is likely that the family association is due partly to genetic factors and partly to shared lifestyles, i.e. diets and patterns o f activity. In some cases obese parents show less concern than average for their children’s obesity, although in other cases the opposite may be true. Low b irth weight. A U-shaped relationship between birth weight and subsequent risk o f obesity appears to apply, with the heaviest babies and the lightest being at risk o f excess weight gain during subsequent childhood and adulthood44. Considerable evidence now exists that obese children and obese adults who had low birth weights are more vulnerable to both coronary heart disease and type 2 diabetes than similarly obese people who had higher birth weights43. Stunting in chil dhood. Stunting (short height for age) affects one-third o f all children aged under 5 years globally (i.e. around 270 million children), most o f them in less developed or transitional economies 46 Evidence from several surveys has shown the co-existence o f stunting and overweight or obesity in the same child and/or among other members o f the same household, in urban areas in developing countries 47,48 and poorer communities in developed countries 4S, One o f the largest studies50 o f nutritional status o f rural school children in low income countries (Ghana, Tanzania, Indonesia, Vietnam and India) found the overall prevalence o f stunting to be high in all five countries, ranging from 48% to 56% 23 University of Ghana http://ugspace.ug.edu.gh 2.6 Environm ental risk factors The changing nature o f the environment towards greater inducement o f obesity has been described in WHO Technical R epo rt10 on chronic disease as follows: ‘Changes in the world, food economy have contributed to shifting dietary patterns, for example, inc reased consumption o f energy-dense diets high in fat, particularly saturated fat, and low in unrefined carbohydrates. These patterns are combined with a decline in energy expenditure that is associated with a sedentary lifestyle— motorized transport, labour-saving devices at home, the phasing out o f physically demanding manual tasks in the workplace, and leisure time that is preponderantly devoted to physically undemanding pastimes.’ (pp. 1-2) It is probable that similar factors are linked to the rise o f overweight in children; for example, a decline in walking to school66 and a rise in snack food consumption67 and the popularity o f fast-food outlets69. W ithin this ‘obesogenic’ environment there are a number o f factors that warrant specific consideration with respect to the risk o f overweight in children and adolescents. It is also important to consider, however, the micro-environment created in the home. For younger children in particular the family environment plays an important role in determining their risk o f obesity, for example parental physical activity levels 51, the family’s eating behaviours51 and television viewing h ab its52. 24 University of Ghana http://ugspace.ug.edu.gh 2.7 Prevention- the only solution Virtually all reviews have indicated that the prevention o f obesity is not only possible but is the most realistic and cost effective approach for dealing with childhood obesity53 as it is for adult obesity 10. Dr D. Satcher, US Surgeon General, 2001 (foreword) A “Many people believe that dealing w ith overweight and obesity is a personal responsibility. To some degree they are right, but it is also a community responsibility. When there are no safe, accessible places for children to play or adults to walk, jog or ride a bike that is a community responsibility. When school lunchrooms or office cafeterias do not provide healthy and appealing food choices that is a community responsibility. When new or expectant mothers are not educated about the benefits o f breast-feeding, that is a community responsibility. When we do not require daily physical education in our schools, that is also a community responsibility . . . The challenge is to create a multi-faceted public health approach capable o f delivering long-term reductions in the prevalence o f overweight and obesity. This approach should focus on health rather than appearance, and empower both individuals and communities to address barriers, reduce stigmatization and move forward in addressing overweight and obesity in a positive and proactive fashion.” The school approach In principle, schools provide an excellent setting for preventing obesity55, and are also the target o f the World Health Organization’s ‘Health Promoting Schools’ programme56 They offer regular contact with children during term-time and 25 University of Ghana http://ugspace.ug.edu.gh provide opportunities for nutrition education and promotion o f physical activity both within the formal curriculum, and informally via the provision o f appropriate facilities within the school environment such as healthy school meals, break-time snack provision and playground equipment. Thus schools not only influence the knowledge and attitudes o f children but also provide opportunities for experiential learning and the development o f a sense o f self-efficacy. Furthermore the school can also provide links with the family and the wider community. 26 University of Ghana http://ugspace.ug.edu.gh 3.0 Methodology and materials. 3.1 S ibdy design A cross-sectional descriptive survey was conducted using quantitative and qualitative data in June 2004 in selected primary schools o f Accra Metropolis. 3.2Variables: • Age • Sex • Weight • Height • BMI » Skin fold thickness • Socio-demographic variables: ethnicity, mother’s and father’s education, type o f school, school fees per term, owning o f a house, own :ng o f a cooker. 3.3 Sampling procedure A Multistage Sampling procedure was carried out in 4 stages: 1. Randomly 4 Accra sub-metros were selected from 8 sub-metros by balloting method. They were: Ablekuma South, Ayawaso, Okaikoi, Kpeshie, 2. Fcur public schools were randomly selected from sample frame o f 56 schools in Ablekuma South sub metro, from sample frame o f 71 schools in Ayawaso sub metro, from sample frame o f 76 schools in 27 University of Ghana http://ugspace.ug.edu.gh Kpeshie sub metro, from sample frame o f 51 schools in Okaikoi sub metro by blind pointing on the random numbers tab le '1, i. e. in each sampling frame ID numbers were assigned to each school (from 1 to56 for Ablekuma South sub-metro, from 1 to71 for Ayawaso sub­ metro,from lto 76 for Kpeshie sub-metro, from 1-56 for Okaikoi sub- metro).Then using a table o f random numbers the researcher closed her eyes and pointed with a pencil a digit on the table. That digit was used to determine the sample unit. I f the selected number was not a valid number, digits were read down the column and then proceed to the upper left top until the first valid number was reached. This procedure was repeated 4 times for each o f the selected sub-metro. 3. The nearest private school to the selected public school was chosen. The aim was to enrich our sample with subjects o f different (possible higher) socio-economic background living in the same area. 4. Selection o f all eligible subjects in the selected schools. The following number o f children was sampled per school: Name o f the sub­ metro Public schools(n) Private schools(n) Ablekuma South Zion Mamprobi - 122 St Anthony -163 Ayawaso Kanda Estate -152- St P a u l-164 Okaikoi Bubiashie St Anglican- 178 New Dimension - 89- Kpeshie Nungua AMA -162 Mandela - 93 28 University of Ghana http://ugspace.ug.edu.gh Sample unit', a child o f age 6-10 years attending one o f the selected public or private primary school in Accra Metro. Study population: Children aged 6-10 years attending primary schools in AMA. 3.4 Sample size determination. A sample size o f 544 was determined based on: Estimate o f obesity prevalence among children o f 3.3%, Worst acceptable o f 1.8%, Population size o f children (aged 5-9 years): 14.6%* 1658937/100%=243366, Confidence Interval o f 95%, In accordance with the Statcalc function o f Epi Info version 3(Centers for Diseases Control and Prevention, Atlanta, GA,USA/ WHO, Geneva, Switzerland). This sample size was multiplied by maximum design effect for cluster sampling o f 2 to give a sample o f 1088. To allow for a non-response rate o f 10% and a non-participation rate o f 10%, 1088 is multiplied by (100/100-20) to arrive at a sample o f 1360. 3.5 Eligibility criteria. 1. The child is 6-10 years old by the 01 June 2004 attending the selected primary school in Accra and is not physically deformed that it would not distort the data. 29 University of Ghana http://ugspace.ug.edu.gh 3.6 Training and Pre-testing Two research assistants were recruited and trained using WHO recommended measurement protocols.21 To standardize survey measurements and procedures, survey team was provided with a copy o f the research protocol and the most relevant sections were discussed, including: -statement o f the problem; -objectives; -data collection technique (age, sex determination, performing height, weight, triceps skin fold thickness measurements) -plan for data collection and handling, etc. Before the main survey pretest study was conducted in class one o f 28 pupils o f Mamprobi Roman Catholic School. The following points were assessed during the Pretest: • Reactions o f respondents to the research procedure; • Availability o f sample needed for full study; • Whether the tools are reliable (adjustment o f the questionnaire); • Time needed for performing anthropometric measures per participant. 2. Obtained informed consent from one of the parents permitting their child to participate in the study. 30 University of Ghana http://ugspace.ug.edu.gh 3.7 Ethical Considerations. Permission to proceed was obtained from Accra Metropolitan Educational Service, Head Master/Mistress o f the selected schools. The study was approved by the Ethical Review Committee o f the University o f Ghana Medical School and complied with the Helsinki Declaration o f 1975 (revised in 1983) on human experimentation and International Ethical Guidelines for Biomedical Research Involving Human Subjects developed by the Council for International Organizations o f Medical Sciences (CIOMS) in collaboration with the World Health Organization (2002)7'" Following ethical issues in research design and procedures were addressed: • Participation in the study was voluntary; • The parents and guardians were informed about their right to refuse to take part in the study; • There was no penalty for refusing to participate; • Expected benefits in obtaining knowledge relevant to the health needs o f children were explained. • Procedures used in the study did not cause physical, mental, or emotional harm. • A child refusal to participate in the research was respected. • Subjects and their parents were informed o f the findings (weight, height, BMI) and health implications were explained. • Utmost discretion and confidentiality were exercised in handling the personal information provided. 31 University of Ghana http://ugspace.ug.edu.gh Informed written consent was obtained from one o f the parents/ guardians before the child participated in the study (Appendix 3). 3.8 D ata Collection, M anagem ent and Analysis The self-administered questionnaire on demographic and socioeconomic status and the consent form were distributed to the parents through the children 1-2 days before anthropometric measurements. Anthropometrical measures were taken in the morning in the school premises on subject in light clothing and without shoes by direct observation. Weight was measured with a Seca770 floor digital scale (Seca, Hamburg, Germany) to the nearest 0.1 kg. It was ensured that the reading was always zero before subjects stepped on the scale. Height was measured w ith a stadiometer to the nearest 0.5 cm. This was placed on a flat floor at each site with subjects standing on the base o f the stadiometer with feet together and back o f head, back o f buttocks, calves and heels all touching the upright. Subjects were then instructed to look straight at spot with head high on the opposite side. Triceps skin fold thickness was measured with skin fold calipers FAT-O-METER (Health and Education Services, Chicago, III) to the nearest 0.5 mm. It was measured in the midline o f the posterior aspect o f the arm at a level midway between the lateral projection o f the acromion at the shoulder and the olecranon process at the ulna which was determined using a tape measure. A vertical fold o f skin and subcutaneous tissue was picked up gently approximately 1cm proximal to the marked level, and the tips o f the calipers were applied perpendicular to the skin fold at the marked level. 32 University of Ghana http://ugspace.ug.edu.gh Age by 01 June 2004 was determined from the school records based on the date o f birth. Quality control checks. Quality control checks were performed for completeness o f entries and internal consistency by principal investigator before leaving the school. On-going supervision o f research assistants was arranged. The weighing scale was checked against two reference scales each morning before commencement o f weighing. \ Data processing and analysis. All data forms were entered using Epi Info 6 and were checked for range and internal consistency. Body Mass Index (BMI) was determined as WEIGHT / HEIGHT2 (kg/m2). The height, weight, triceps skin fold thickness and BMI percentiles were calculated against the international growth reference (CDC 2000 Epi Info Nutrition program). Nutritional status was classified as follow: those w ith BMI scores>85ft and<95fll percentile were considered at risk o f overweight and those with BMI s c o r e ^ S * percentile were considered obese, those with BMI scores <5* percentile were considered underweight, those with BMI>5 and<85 percentile were considered normal. Nutrition programme, Epi Info, Version 6 (CDC, Atlanta, GA, USA/WHO, Geneva Switzerland) and the statistical package SPSS 10,0 for Windows (SPSS, Inc., Chicago, IL, USA) were used for analysis. Statistical tests included the Chi square test for discrete variables and student’s t- 33 University of Ghana http://ugspace.ug.edu.gh test for normally distributed data. Results were considered statistically significant if p-value < 0.05. 3.9 Limitations of the study. As a result o f limited logistics and time the survey was limited to children attending primary schools excluding out o f school children which could limit generalization o f results. The self-administered questionnaires which was giving out to the parents resulted in lower response rate on socio-demographic status o f the children. The prevalence o f obesity in the analysis was not age and sex specifically adjusted as the age range in the sample was too small. 34 University of Ghana http://ugspace.ug.edu.gh 4.0 Results. In total 1123 children (584(52%) females and 539(48%) males) aged 6-10 years took part in the study from 1st to 30th June 2004 in Accra Metropolis. There were however, 912 questionnaires on socio-economic status available for further analysis. General characteristics of the study population. The survey was carried out in the 8 primary schools in Accra. Sex distribution in the schools did not differ significantly (p=0.057). Table 1 shows the name, type, school fees per term o f selected for study schools. Table 1. Characteristics of participated schools. Area Public Private Name o f the school School fees per term (0) Name o f the school School fees per term (0) Mamprobi Mamprobi Zion 53,000 St. Anthony 780,000 Bubiashie St. Joseph Anglican 55,000 New Dimension 370,000 Kanda Kanda Estate 13,500 St. Paul 800,000 Nungua Nungua AMA 13,500 Mandela 530,000 35 University of Ghana http://ugspace.ug.edu.gh Table 2 shows the mean ± SD o f age, weight, height, skin fold thickness and BM I for males and females. Mean weight as weil as mean B M i and mean skin fold thickness in male subjects were significantly lower than that o f female subjects. Also girls appear to be taller than boys. Table 2. Mean value ± standard deviations of selected variables of the study population. G ender Mean age (years) Mean weight (kg ± SD) Mean height (cm ± SD) Mean skin fold (mm ± S D) i Mean S M I ! (kg m '"± ! SD) males(539) 8.43 ± 1.2* 26.8 ± 5.1* 128.3 ± 8.6* 6.76*3.5* 16.1 ± 1.7* females(584) 8.41 ± 1.2* 28.3 ±6.7* 130.0 ±9.1* 9.61 ±4.9* i 16.5 ± 2.2* Total (1123) 8.42 ± 1.2* 27.6 ±6.0* 129.2 ± 8.9* 8.24 ± 4.5* ■ 16.3 * 2.0* * p = 0.00 F igurel represents gender distribution in the sample by ages. There was no statistical difference in distribution o f sexes between age groups (*p 0.681). Sex ratio female/ male in the sample was 1.1 :1 Mean BM I distribution by gender and age is shown in Figure 2. G irls appear to be “heavier” in all age groups except in the 6 years group where mean BMI for males was higher. Generally, BM I increased with age. 36 University of Ghana http://ugspace.ug.edu.gh Figure 1. Gender distribution by age. □ male E3 female 60% 50% g 40% 8 30% | 20% 10% 6 7 8 9 10 Age (years) Figure 2. D istribution of mean BM I by gender and age.* ;Dm a le ' □ fema!e| ■ I * p = 0 .0 0 37 University of Ghana http://ugspace.ug.edu.gh Figure 3 shows the distribution o f mean skin fold o f boys and giris by age group. In girls, skin fold thickness increased with age. The pattern was less clear in boys. Figure 3. Mean skin fold thickness d istribu tion by gender and age*. *p=0.00 The age distribution by ethnic group is shown in Figure 4. Akan and Ga-Adangbe were predominant groups. □ male o female 6 7 8 9 10 Age(yeare) 38 University of Ghana http://ugspace.ug.edu.gh Figure 4, Ethnic distribution by age. 43o S ' 3 CO Age (years) □ Akan 0 Ewe □ Ga-Adangbe □ Other Figures 5 and 6 show weight for age on C D C curves o f a ll females and males respectively (CDC 2000 Reference, Nutrition, Ep i Info). The weight was normally distributed for both gender and ranged from 14.4 kg to 59.3 kg among girls and from l6.4kg to 50.1kg among boys. The median for females and males were 27.1 kg and 26.8kg, respectively. The respective modes for females and males were 27.2kg and 23.3kg. Figures 7 and 8 show BM I on CD C curves o f female and male subjects ( CDC 2000 Reference, Nutrition, Ep i Info). The BM I was normally distributed for boih gender and ranged from 11.9 kg/m2 to 28.6 kg/m2 among girls and from 12.1 kg/m -25.0 kg/m2 among boys. The median for females and males were 16.1 39 University of Ghana http://ugspace.ug.edu.gh kg/m2 and 15.9 kg/m2, respectively. The respective modes for females and males were 15.48 kg/m'' and 16.6 kg/m2 Table 3 shows the distribution o f ethnicity by gender. There was no significant difference in distribution o f ethnic groups by gender and age groups. Table 3. D istribu tion n (%) of ethnic groups by age and gender. Akan Ewe Ga- Adangbe Other Male* Age 6 10(35.7) 6(21.4) 10(35.7) 2(7.1) 7 28(47.5) 6(10.2) 20(33.9) 5(8.5) 13(10.9)8 43(36.1) 15(12.6) 48(40.3) 9 46(36.2) 16(12.6) 46(36.2) 19(15.0) 10 33(32.4) 18(17.6) 34(33.3) 17(16.7) All males 160(36.8) 61(14.0) 158(36.3) 56(12.9) Female** 6 17(56.7) 2(6.7) 8(26.7) 3(10.0) 7 23(32.4) 10(14.1) 25(35.2) 13(18.3) 8 56(42.1) 21(15.8) 43(32.3) 13(9.8) 9 48(36.4) 15(11.4) 51(38.6) 18(13.6) 10 45(40.0) 16(14.4) 32(28.8) 18(16.2) All females 189(39.6) 64(13.4) 159(33.3) 65(13.6) *p 0.631 **p 0.483 40 University of Ghana http://ugspace.ug.edu.gh W eig ht ( kil os ) Figure 5. Weight For Age Of Ail Females 100 - 95% 95 90 90% 85 80 75 70 75% 65 50% 60 55 50 45 - 40 35 ■ 30 25 ■ 20 15 10 X ! / 1 . / l • / */ */ 8 .« / I 25% 10% 5% a aii Females 41 University of Ghana http://ugspace.ug.edu.gh W eig ht ( kil os ) Figure 6 Weight For Age O f All Males 95% 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 90% 75% I M 50% 25% 10% 5% All Males 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Age (yrs) 42 University of Ghana http://ugspace.ug.edu.gh BM I Figure 7. BMI For A9e ° f AI1 Fema|es 3 6 ---------- — ----------------------------------- ------------- 111 95% I 34 32 30 26 12 10 ,----------•-------- '-------■------ --------------------.--------r---_ ----------- t--------,-------- t--------,--------,-------- ,------- ,------- 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Age (yrs) 90% 8 | 85% H 75% H 50% M 10% H 5% ! B All Females 43 University of Ghana http://ugspace.ug.edu.gh BM I T t g U r g l i r BMI For Age O f All Males : H 95% E3 90% H 85% S 75% H 50% HI 25% H 10% H 5% H All Males 2 3 4 5 6 7 3 9 10 11 12 13 14 15 16 17 18 19 20 Age (yrs) 44 University of Ghana http://ugspace.ug.edu.gh The corresponding crude prevalence of obesity by CDC 2000 reference criteria was 3.4% (95%CJ .14%- 4 7%).The corresponding crude prevalence at risk of overweight was 7% (95% Cl 5.6%-8.7%).The prevalence of underweight by CDC criteria was .3.7% (95%C1 2.7% -5.1%). F igure 9. N utritional status of p rim ary school children in Accra. Figure 9 shows distribution o f BMI categories in the study population. 5% 4 .8% -j O0/_ 80 .1% □ Underweight m Normal □ At risk □ Obese Figures 10 and 11 present gender specific distribution o f BMI in the sample and by CDC 2000 reference criteria. According to these figures the rate o f obesity and risk of overweight as well as underweight was higher in females than males (p = 0.000). The Figures 12 and 13 show distribution of BMI categories by age in each gender. The highest prevalence of obesity and risk o f overweight in females occurred in the 10 years group. In males, 7 years group had the highest prevalence o f obesity and 10 years group had the highest risk o f overweight. There were no obese subjects in the youngest age group in both genders. In contrast there were no 45 University of Ghana http://ugspace.ug.edu.gh underweight boys in 10 years group Highest rates o f underweight were observed in 8 years group in males and 7 years group in females. F igure 10. D istribution BMI categories by gender. 90 80 70 2 60 « 50 c 0 | 40 £ 30Q. 20 10 0 85 . 5 . “ 379' -5J- 7.8 12.3 □ male 0 female u/weight normal at risk obese N u trit iona l s ta tu s F igure 11. D istribution BM I categories by gender by CDC criteria . □ male £3 female Nutritional status 46 University of Ghana http://ugspace.ug.edu.gh Figure 12. Distribution of BMI categories by age in girls. Age(years) □ Underweight n At risk of overweight □ obese F igure 13. D istribution of BMI categories by age in boys. A ge(years) □ underweight m at risk of overweight □ obese Table 4 represents distribution o f means + SD o f the selected variables by schools. The lowest number o f subjects (7.9%) was in Bubuashie private school, followed by Mandela private (8.3%), among public schools the lowest proportion o f participants was in Mamprobi Zion school (10.9%). Kanda Estate school had 47 University of Ghana http://ugspace.ug.edu.gh the highest mean weight (29.8kg) and the highest mean height (134.3cm). Subjects o f Bubiashie St. Joseph school had the lowest mean BMI (15.6kg/m2) while subjects o f St. Anthony school had the highest mean BMI (17.2kg/m2).Children o f St. Anthony school also had the highest mean skin fold thickness (17.2mm) and the lowest mean o f skin fold thickness was noticed in Mamprobi Zion school. Prevalence o f obesity reflects distribution o f mean BMI: the highest proportion o f obese children was at St. Anthony school (12.3 %), closely followed by S tPaul school (12.2%) and none o f the participants at Nungua AMA school was obese followed by Bubiashie St. Joseph school where obesity prevalence was 0.6%. Table 4. Distribution o f means ± SD o f selected variables and obesity prevalence by schools (p=0,00) Variables Mean values ±SD School Zion Mamp robi Bubiashie StAnglcan Kanda Estate Nungua AMA St Anthony New dimension StPaul Mandel Age 8.5 ± 1.2 8.2 ± 1.1 8.9 ± 1.1 8.5 ±1 .2 8.5 ±1.1 8.5 ±1.3 41o00 r—< 8.4 ±1 . Weight 26.5 ± 5.4 24.2 ± 4.2 29.8 ± 5.9 24.7 ±4.1 29.6 ± 7.0 28.9 ±7.1 28.9 ± 6.8 28.2 ± f Height 128.6± 9.4 125.7±6.9 134.3±9.8 125 ±7.3 130.6±8.3 130.7±9.4 129.9± 8.3 130.6±f Skin fold 5.9 ± 2.2 7.2 ± 2,3 7.7 ±3.3 6.1 ±2,4 11.2 ± 5.6 8.7 ±5.5 10.4 ± 5.8 8.6 ±4. BMI 15.9 ± 1.4 15.6 ± 1.7 16.4 ± 1.6 15.7 ±1.3 17.2 ±2 .4 16.7 ±2 .2 16.9 ± 2.7 16.4 ± : %obese 1.6 0.6 2.6 0 12.3 6.7 12.2 3.2 N(%) subjects 122 (10.9) 178(15.9) 152(13.5) 162(14.4) 163(14.5) 89(7.9) 164 (14.6) 93(8.3) 48 University of Ghana http://ugspace.ug.edu.gh Prevalence o f obesity and risk o f overweight were higher in the private schools 9.6% (CDC 7.1%) and 14.1% (CDC 10.8%), respectively than that in the public schools where prevalence o f obesity was 1.1% (CDC 0.3%) and risk of overweight was 6.8%(CDC 3.9%). Opposite pattern was noticed in distribution of underweight: the prevalence was higher in the public schools 6.4% (CDC 5%) and that for private 2.9% (CDC 2.2%). F igure 14. D istribution of BMI categories by the type of schoo! Figures 14 and 15 show the distribution of BMI by the type of school. Nutritional status 49 University of Ghana http://ugspace.ug.edu.gh Figure 15. Distribution of BMI categories by the type of school by CDC criteria- 0oc0 ca>0i— o_ 100 90 80 70 60 50 40 30 20 - 10 0 90.7 80 P 5.0 . , 10'8 7.1 I Irrrsra ... r i * r n u/weiglit normal at risk obese Nutritiona l sta tus | □ public j C3 private Table 5 shows distribution o f BMI categories by gender and type o f schools. Females were more obese than boys in both public and private schools. There were more obese subjects in the private schools than in public schools. There were more underweight girls than boys in both type o f schools and more underweight subjects in the public schools than in private schools. 50 University of Ghana http://ugspace.ug.edu.gh Table 5. D istribution o f BM i categories by sex and type o f school by CDC criteria* Gender/School D istribution of BMI categories N (% ) u/weight normal at risk obese Total Male Private 5(2.1) 200(84.4) 21(8.9) 1 1(4.6) 237(100) Public 14(4.6) 275(91.1) 13(4.3) 0(0) 312(100) Female Private 6(2.2) 207(76.1) 34(12.5) 25(9.2) 272(100) Public 17(5.4) 282(90.4) 11(3.5) 2(0.6) 312(100; Total 42(3.7) 964(85.9) 79(7.0) 38(3.4) 1123(100) *p<0.001. Table 6 represents distribution o f BMI categories by paid school fees. The highest prevalence o f obesity and at risk o f overweight was in the schools with the highest charge rate. Schools with the lowest charge rate had the highest underweight prevalence. Table 6. D istribution of BM I categories by school fees category*. School fees Distribution o f BMI categories n (%) per term u/weight normal at risk obese Total <55,000 39(6.4) 526(85 .7) 42(6.8) 7(1.1) 614(100) >55,000 - < 530,000 5(2.7) 145(79.7) 23(12.6) 9(4.3) 182(100) >530,000 10(3.1) 228(69 .7) 49(15) 40(12 2) 327(100)11 Total 54(4.8) 899(80 .1) 114(10.2) 56(5 0) 1123(100) * p =0.000 51 University of Ghana http://ugspace.ug.edu.gh Ethnicity by BMI categories are given in Table 7. Underweight was least prevalent among Akan ethnic group. Obesity and risk of overweight prevalence were highest among Akan and Ewe tribes. Table 7. D istribution of BM I categories by ethnic affiliation'''. D istribution of BM I categories N (% ) Ethnicity Underweight Normal At risk of overweight Obese Total Akan 10(2.9) 270(77.4) 39(11.2) 30(8.6) 349 Ewe 4(3.2) 97(77.6) 17(13.6) 7(5.6) 125 Ga-Dangbe 16(5) 258(81.4) 28(8.8) 15(4.7) 317 Other 11(9.1) 94(77.7) 15(12.4) 1(0.8) 121 Pearson Chi-square test 21.666“ d f 9 *p 0.01 Table 8 shows distribution BMI categories by father’s educational level. Obesity and at risk o f overweight prevalence was higher in subjects whose father had tertiary education. Children o f fathers with primary/ middle education had the highest underweight prevalence. Obesity rates tended to increase with increase of father's level o f education. T able 8. D istribution of BM I categories by Sevel o f fa th e r’s education* D istribu tion of BM I categories N (% ) F a th e r’s education Underweight Normal A t risk of overweight Obese Total No forma! education 1(2.3) 42(95.5) 1(2.3) o 44(100) Primary/middle 10(5.1) 166(84.3) 18(9.1) 3(1.5) 197(100) | Secondary/ Technical 19(3.9) 384(79) 51(10.5) 32(6.6) 486(100) Tertiary 5(3.4) 104(70.3) 25(16.9) 14(9.5) 148(100) Total 35(4) 696(79.5) 95(10.9) 49(5.6) 875(100) Pearson Chi-square 33.942a d f9 *p= 0.002 University of Ghana http://ugspace.ug.edu.gh Mother’s educational level by BMI categories is shown in Table 9. Children o f mothers who had tertiary education had the highest obesity and at risk o f overweight prevalence. The highest proportion o f underweight children was among mothers with no formal education. T able 9. D istribution of BMI categories by level of m o ther’s education D istribu tion of BM I categories N (% ) M other’s education Underweight Normal A t risk of overweight Obese Total No formal education 5(4.7) 89(84) 9(8.5) 3(2.8) 106(100) Primary/middle 15(4.5) 282(84.4) 28(8.4) 9(2.7) 334(100) Secondary /’ Technical 16(4.2) 281(74.5) 49(13.0) 31(8.2) 377(100) Tertiary 1(2) 36(73.5) 7(14.3) 5(10.2) 49(100) Total 37(4.3) 688(79.4) 93(10.7) 48(5.5) 866(100) *Pearson Chi-square 32.220a d f9 p=0.013 TablelO represents nutritional status o f children whose parents own or not own the house, cooker. The highest prevalence o f obesity was among “owners” than that among “non-owners” By contrast, “non-owners” had the highest prevalence o f underweight than “owners” 53 University of Ghana http://ugspace.ug.edu.gh Table 10. D istribution o f BM I categories by possession o f the house* and cooker** D istribution of BM I categories N (% ) House owner Underweight Normal A t risk of overweight Obese I Total j j 1. ... . f ..... No 44(5.7) 628(80.8) 77(9.9) 28(3.6) j 777 Yes 10(2.9) 271(78.3) 37(10.7) 28(8.1) j 346 Possession of a cooker J No 22(6.0) 309(84.2) 28(7.6) 8(2.2) | 367(100) Yes 18(3.3) 405(75.0) 72(13.3) 45(8.3) j 540(100) *Pearson Chi square 13.833a d f3 *p 0.003 **Pearson Chi square 26.463a d f 3 **p 0.000 Tablel 1 represents reliability o f skin fold thickness in measuring o f obes ity prevalence o f obesity using skin fold thickness was 5.3% and that using 8MT was 5%. There was good agreement between BMI and skin fold thickness (Kappa 0.636) and there was strong positive association between these two indices (r 0.702). T able 11. Agreem ent between BM I and skin fold th ickness in diagaosing «f obesity. fold BMI Obesity p resen t (n) No obesity (n) Total a (% ) Obesity present (n) 38 18 56(5) , No obesity (n) 22 1045 1067(95} | Total n (% ) 60(5.3) 1063(94.7) 1123(100) Kappa 0.636 p = 0.000 Table 12 shows linear relationships between age, weight, height, BMI and skin fold thickness. There was also strong positive association between skin iM I 54 University of Ghana http://ugspace.ug.edu.gh thickness and weight (r 0.628) and positive but weak association with age (r 0.118) and height (r 0.299). BMI was also positively associated with age(r 0.204). Weight and height were strongly associated with age (r 0.516 and r 0.647). Table 12. Correlation between age, BMI and skin fold thickness. BMI AGE Skin fold thickness WEIGHT HEIGHT BMI Pearson Correlation 1 .204 .702 .793 .345 Sig. (2- tailed) .000 .000 .000 .000 AGE Pearson Correlation .204 1 .118 .516 .647 Sig. (2- tailed) .000 .000 .000 .000 Skin fold thickness Pearson Correlation .702 .118 1 .618 .299 Sig. (2- tailed) .000 .000 .000 .000 WEIGHT Pearson Correlation .793 .516 .618 1 .826 Sig. (2- taiied) .000 .000 .000 .000 HEIGHT Pearson Correlation .345 .647 .299 .826 1 Sig. (2- tailed) .000 .000 .000 .000 55 University of Ghana http://ugspace.ug.edu.gh Tables 13 and 14 represent partial correlation between weight, height, BMI and skin fold thickness controlling for age and sex. There was also strong positive correlation between skin fold thickness and BMI, skin fold thickness and weight. Table 13. Partial correlation between weight, height, BMI and skin fold thickness, controlling for age. Weight Height BMI Skinfold thickness Weight Coefficient 1.0000 .7534 .8201 .6558 Sig.(2-tailed) P= .000 P= .000 P= .000 Height Coefficient .7534 1.0000 .2849 .2950 Sig.(2-tailed) 11 © o o P = .000 oo01 BMI Coefficient .8201 .2849 1.0000 .6977 Sig.(2-tailed) P= .000 P= .000 P= .000 Skinfold thickness Coefficient .6558 .2950 .6977 1.0000 Sig. (2-tailed) P= .000 P= .000 P= .000 56 University of Ghana http://ugspace.ug.edu.gh Table 14. Partial Correlation between weight, height, BMI and skin fold thickness, controlling for sex. Weight Height BMI Skinfold thickness Weight Coefficient 1.0000 .8246 .7903 .6142 Sig.(2-tailed) P= .000 P= .000 P= .000 Height Coefficient .8246 1.0000 .3383 .2862 Sig. (2-tailed) P= .000 P= .000 P= .000 BMI Coefficient .7903 .3383 1.0000 .7097 Sig.(2-tailed) P= .000 hd II © o o P= .000 Skinfold thickness Coefficient .6142 .2862 .7097 1.0000 Sig.(2-tailed) P= .000 P= .000 OO01 57 University of Ghana http://ugspace.ug.edu.gh 5. Discussion. In the present descriptive cross-sectional survey data is presented on burden o f overweight and underweight in primary school children in Accra the most urbanized area in the country. The study also provides useful baseline data on socio-demographic aspects o f obesity in older children (5-10 years). Most o f the available data that do exist are collected for pre-school children and focus on malnutrition. It is notable that over nutrition and nutrition-related chronic diseases are on the increase in developing countries due to changes in life style with altered difet and diminished physical activity. The study in Accra found growing problem o f obesity and overweight in adults. 640verall crude prevalence o f obesity and overweight was 14.1% and 23.4%, respectively. Obesity generally tracks from childhood into adulthood39,41. It is probable that similar factors are linked to the risk o f overweight in children; for example, a decline in walking to school and a rise in snack food consumption and the popularity o f fast foods outlets. The present study revealed that overall crude prevalence o f obesity and at risk o f overweight in primary school children in Accra was 5% and 10.2%, respectively. That corresponds with findings o f recent study conducted among pre-school children from 24 Sub Saharan countries.28 The prevalence o f obesity was below 5% in all countries, except Malawi. It is interesting to notice that prevalence o f underweight was almost the same as obesity 4.8%. The proportions o f obese and at risk o f overweight children by CDC criteria22 was less than ones derived from the sample percentiles 3.4% and 7%, respectively. This discrepancy may be 58 University of Ghana http://ugspace.ug.edu.gh attributed to the fact that curves come from more affluent American population with a high prevalence o f obesity (15%)54. Despite growing concern about weight related problems among children no universally accepted classification system for childhood obesity exist, although the choice o f BMI as a measure is fairly established19. But number o f problems associated with BMI as a measure o f adiposity in childhood. In children BMI varies with age and sex, maturation patterns also influence these variations. In addition, increases in BMI during childhood growth seem to be attributable mainly to muscular gains, unlike in adults where adiposity gains dominate70. It has been recommended that BMI use requires additional measures to confirm excess body fat. In this study skin fold thickness was chosen as an additional measure o f fatness. Overall prevalence o f obesity by skin fold thickness distribution wa<- 5.3% and that using BMI was 5%. There was good agreement between BMI and skin fold thickness (Kappa 0.636) and there was strong positive association between these two indices (r 0.702). There was also strong positive association betv/een skin fold thickness and weight (r 0.628) and positive but weak association with age (r 0.118). BMI was also positively associated with age (r 0.204). These two indices may be recommended for future growth monitoring programs in Ghana From the present study the percentage o f obese and at risk o f overweight girls was more than twice that o f boys (7% verse 2 .8%). It is matches with findings o f the study64 on adults, where female were more obese and overweight than males. 59 University of Ghana http://ugspace.ug.edu.gh Obesity prevalence in females was higher in all age group than that in males except 6 years group. In both genders subjects from private were more at risk o f excessive weight gain than their counterparts from the public schools. Prevalence o f obesity and at risk o f overweight in the private schools was 9.6% and 14.1% and that for public schools was 1.1% and 6.8%. Using the type o f school (private or public) and amount of school fees paid as a proxies o f economic status, my findings confirm that overweight is high among the rich in lower income countries27.This is contrary to reports from Western world, where subjects from affluent families tend to have lowest rates o f obesity than do have subjects from less affluent families. In contrast, underweight was relatively higher in the public schools compared to private schools (6.4% verse 2.9%). Among possible reasons accountable for high obesity rates in children from higher social background may be riding in cars to schools and other places, watching video games and therefore less physically active, they are more likely to afford fast food and drinks. Looking at possible socio-demographic determinants o f obesity it is interesting to note that obesity was highest in Akans (8.6%) and the risk o f overweight was highest in Ewes (13.6%) and Akans (1 1.2%).The observed differences presumably lie in dietary and cultural pattern o f people concerned. Further research is however needed to confirm these findings and to ascertain reasons for the ethnic differences. Subjects whose father had tertiary education tended to be more obese or overweight. Prevalence o f obesity and at risk o f overweight in this 60 University of Ghana http://ugspace.ug.edu.gh group were 9.5% and 16.9%, respectively. Prevalence o f underweight was highest in subjects whose father had only primary education (5.1%). Similar trends were observed in distribution o f BMI categories among mothers with respect o f level o f education. Mothers with tertiary education tended to have more obese children (10.2%) and children at risk o f overweight (14.3%). In contrast, mothers without formal education had more underweight children. 6. Conclusion and Recommendations 6.1 Conclusion Obesity does not appear to be a major problem in primaiy school children in Accra. The study however provides useful baseline information for future monitoring o f trends. A significant number, a tenth o f the children, were in the at risk o f overweight category. There was co-existence o f obesity and underweight in primary school children. Economic status appeared to be an important determinant o f nutritional status. Subjects in private schools had higher rates o f overweight and obesity compared to subjects from public schools. Also higher school fees and tertiary education o f parents were associated with higher rates o f obesity. In contrast underweight was lowest in private schools and associated with lower school fees and low parental education. Further work is needed to ascertain the real reasons for observed differences. The results o f the study suggest that improved living conditions in urban areas in population adapted to chronic food shortages increase the susceptibility to obesity and nutrition related chronic 61 University of Ghana http://ugspace.ug.edu.gh diseases. There is a need for policy shift towards organized and co-coordinated health promotion to combat an increasing trend o f overweight and obesity. 6.2 Recommendations. 1. Continued collection o f data on nutritional status o f school age children is essential for development o f national reference charts to monitor their growth and development patterns. 2. Developing effective education programmes for the public, health professionals to increase awareness o f the causes and consequences o f obesity as well as the methods for its prevention. 3. Schools are the main institutions able to reach a large number o f children and young people. They can promote health and prevent diseases through healthy eating and exercise. 4. Urban planners can support increased physical activity by building recreational facilities, such as parks and play grounds. 5. Further research into determinants o f obesity and metabolic risk profile at younger ages should be undertaken. 62 University of Ghana http://ugspace.ug.edu.gh References. 1 World Health Organization. Obesity: Preventing and Managingthe Global Epidemic. Report o f a WHO Consultation. WHOTechnical Report Series no. 894. WHO: Geneva, 2000. 2. Standing Committee on Nutrition: L.Drake et al. School-Age Children: Their Nutrition and Health. SCN News 25, Dec 2002. 3. 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Jahns L, Siega-Riz AM, Popkin BM. The increasing prevalence o f snacking among US children from 1977 to 1996. J Pediatr 2001; 138; 493-498. 68. St-Onge MP, Keller KL, Heymsfield SB. Changes in childhood food consumption patterns: a cause for concern in light o f increasing body weights. Am J Clin Nutr 2003; 78: 1068-1073. 69. ACC/SCN(2000).Fourth Report on the World Nutrition Situation. Geneva: ACC/SCN in collaboration with IFPRI. 70. Maynard LM, Wisemandle W, Roche AF, Chumlea WC. Childhood body composition in relation to body mass index. Pediatrics 2001; 107: 344-350. 71. Arvanitis LC, Portier KM, Simple Random Selection. Natural Resource. University o f Florida, 1997. http ://i fasstat. ufl. sdu/nrs/SRS 72. International Ethical Guidelines for Biomedical Research Involving Human Subjects CIOMS. Geneva. http://wsvw.cioms.clT/fraiTie guidelines nov 2002.htm 71 University of Ghana http://ugspace.ug.edu.gh Questionnaire on socioeconom ic status of the primary school children. Explanatory N o ;e: The purpose o f this questionnaire is to collccl information on effect of demographic and socioeconomic factors on nutritional status o f children attending primary schools in Accra.-Utmost discretion and confidentiality w ill be exercised in handling the information provided. We thank you in advance for your participation. Questions 1,2,4. 7 fill appropriate and the rest o f the questions thick appropriate. 1, Full name o f the child: 2. Date o f birth of the ch ild :_______________________ ?. Sex o f the child: M _ / F / 4. Residential a rea :__________ 5. Ethnicity: Akan Other / / Ewe________/ Ga-Adangbe______ / 6. Type o f school: Pub lic___ 7. School fees per term (cedi): / Private / / 8. Wha; was the highest level o f education your father completed: None / Primary/ / Secondary/Technical_____ / University /Polytechnic/ j Not known / 9. Wha:' was the highest level o f education your mother completed: None / Primary/ m idd le / Secondary/ Technical I University/Polytechnic_______ / Not known / 10. Father's employment: Employed at present__________/ Unemployed _____ / 72 University of Ghana http://ugspace.ug.edu.gh 11.Mother’s employment: Employed at present_______ / Unemployed__________ / Not known___________ / 12. Number o f sisters and brothers living in the same house:______________ / 13. Parents living at home: Mother on ly_______ / Father on ly_______ / Mother and father / Neither paren t__________ / 14. Grandparents living at home: One grandmother____ / One grandfather_____ I Both o f th em _______ / None o f them / 15. Do the parents own a house: Yes / N o _ / 16. Do the parents rent a house: Yes_____/ No / 17. How much do they pay for the rent: Less 200,000 cedi/month_________ / 200,000-500,000 cedi/month______ / More 500,000 cedi/ month_________/ 18. Do the parents possess a car: Yes____/ No__ J 19. Do you have a TV set in your house: Yes___ J No_____/ 20. Do you subscribe to any TV programme(M-Net, Multichoice): Yes /No I 22. Do the parents possess a refrigerator: Yes___ I No________I 23. Do you have a cooker in the house: Yes / Noj________ I Not known__________ / 73 University of Ghana http://ugspace.ug.edu.gh INFORMED CONSENT FOR STUDY ON NUTRITIONAL STATUS OF THE SCHOOL-AGE CHILDREN. PARENT’S NAM E :......................................................... DATE: WARD’ S NAME: ........................ INTRODUCTION Your ward has been invited to participate in the survey on nutritional status o f the school-age children. This study is being conducted by the School o f Public Health, University o f Ghana in collaboration with National Diabetes Management and Research Center, Korle-Bu. The aim o f this study is to assess the extent o f the most common nutritional problems such as under- and overweight among school-age children. The information may assist us develop programmes to address the any problems identified. Early prevention is essential and cost-effective in order to prevent nutrition-related chronic diseases. Participation in this study is voluntary. Your ward will not be affected by your refusal to let him/her participate in the study. The procedures involved in the study are simple and safe and involve measuring weight, height and skin fold thickness. These procedures would not cause any physical, mental or emotional harm to your ward. The measurements will be made available to parents. All personal information gathered in the study will be kept confidentially. If you have any problems or questions about this study you should contact principal investigator Dr. S. Aduama, p.o. box 77, Korle- Bu, tel.027-7512388. CONSENT I have read about this study and understood its nature. I hereby consent to permit my ward to take part in this study. SIGNATURE / THUMB PRINT OF THE PARENT.......................................... DATE..................... SIGNATURE OF INVESTIGATOR DATE.................... 74 University of Ghana http://ugspace.ug.edu.gh