Arterial Stiffness in Type 2 Diabetes Patients in Ghana

Abstract

Diabetes mellitus is associated with increased risk of cardiovascular diseases (CVDs) and mortality. Type 2 diabetes (T2DM) exerts it deleterious effects through the blood vessel which may lead to hypoperfusion and end organ damage. The ability to characterize the arterial system and derive related biomarkers that can predict the occurrence of CVDs and discriminate high risk subject for management would be of immense importance. Assessment of arterial stiffness and central hemodynamic indices had been shown to predict CVD events in healthy and diseased Caucasian and Asian population; few studies had been reported of the utility of arterial stiffness assessment in sub-Saharan Africa. This study measured the levels of arterial stiffness and central hemodynamic indices in Ghanaian T2DM subjects with and without hypertension, and compared to the levels in age and gender matched nondiabetes subjects with and without hypertension; in order to assess the impact of arterial stiffness in diabetes and hypertension conditions. Also, the associations of vibration perception threshold (VPT) and vascular growth factors, angiopoietin (ang)-1, ang-2 and vascular endothelial growth factors (VEGF), to the levels of arterial stiffness were investigated. In this study, 197 individual, composed of 68 hypertensive T2DM subjects, 46 nonhypertensive T2DM, 48 nondiabetes hypertensive subjects and 35 nondiabetes normotensive subjects volunteered to participate. Anthropometric characteristic and blood pressure measurement were performed. VPT was measured with Horwell Neurothesiometer and arterial stiffness was assessed using Tensiomed Arteriograph and Vasera. Fasting blood samples were collected from all the participants and nondiabetes subjects were screened for diabetes using the oral glucose tolerance test. Plasma glucose and lipid profile were assayed whereas vascular growth factors were assayed with ELISA. The study showed that aortic pulse wave velocity (PWV), heart-ankle (ha) PWV and aortic pressure indices were highest in hypertensive T2DM subjects, followed by nondiabetes hypertensive subjects, then the nonhypertensive T2DM subjects, and the control subjects with the lowest levels. However, cardio-ankle vascular indices (CAVI) was highest in hypertensive T2DM subjects, followed by nonhypertensive T2DM subjects, and then the nondiabetes hypertensive subject, with the control subjects having the least levels. The study also showed that female subjects had higher levels of aortic stiffness than the male counterpart, though no difference in CAVI and ha-PWV was observed. Arterial stiffness indices were found to generally increase with increasing age, duration of diabetes and body composition indices. Subjects with peripheral sensory neuropathy (PSN) were found to have higher levels of arterial stiffness indices than those without PSN. Of vascular growth factors, ang-2 was found to be associated with central aortic pressure and indices ang-1 was found to be associated with VPT. The findings of this study showed that diabetes and hypertension are associated with arterial stiffness in Ghanaians. Arterial stiffness is associated with impaired angiogenesis in Ghanaians. Arterial stiffness might also contribute to the development of PSN in Ghanaians.