Background: The association of insulin resistance (IR) with other cardiometabolic risk (CMR) factors in sub-Saharan Africans is poorly documented. This study examined the links between IR and the evolution of blood pressure (BP), glycaemia, serum lipids and abdominal obesity in the population of Benin.
Design: Population-based longitudinal study.
Methods: This study initially included 541 apparently healthy Beninese adults (50% women) aged 25-60 years who were randomly selected in a large city, a small town and a rural area. After a baseline survey, our subjects were followed up after 2 years, and again at 4 years. IR based on homeostasis model assessment (HOMA), blood glucose, BP, waist circumference (WC), triglycerides, total cholesterol and HDL-cholesterol were measured. Complete data at the end of the follow-up periods was available for 416 subjects.
Results: IR was more prevalent in women than in men (33.2% versus 17.8%) and it was generally associated with more adverse values of CMR factors, excepting BP. In controlling for baseline age, sex, WC, diet, lifestyle variables and WC changes; the relative risk (RR) of hyperglycemia over 4 years was as least 3-fold in IR subjects, compared to normal subjects. The RR of abdominal obesity was 5.3 (1.04-26.93) in IR women, compared to non-IR. The association of IR with the evolution of dyslipidemia was inconsistent, but IR tended to exacerbate low HDL-cholesterol.
Conclusion: Over 4 years, IR exacerbated hyperglycemia in both men and women, and abdominal obesity in women, but IR did not affect blood pressure. Further research on the link found between IR and dyslipidemia, particularly low HDL-C, is needed in sub-Saharan Africa.
Keywords: Abdominal fat; Benin; blood glucose; blood pressure; cardiometabolic risk factors; dyslipidemia; epidemiology; hyperglycemia; insulin resistance; sub-Saharan Africa.