Prevalence of diabetes mellitus and impaired glucose tolerance in a group of urban adults in Nigeria.

This survey was undertaken to determine the prevalence of diabetes mellitus and impaired glucose tolerance in a group of urban adults in Ibadan, Nigeria. A total of 998 subjects randomly selected from five main ministries and departments in the Government Secretariat participated in the survey. Each subject was asked to fast overnight and ingested 75 g of glucose dissolved in 250 mL of water after answering a questionnaire. Relevant anthropometric measurements such as weight, height, waist and hip diameters, and blood pressure also were taken. After 2 hours, of blood was drawn and plasma glucose concentration measured. Diagnosis of diabetes or impaired glucose tolerance was based on 1985 World Health Organization (WHO) cut-off values. Blood glucose results were available in 875 subjects. Seven subjects were found to be diabetic for a prevalence of 0.8%, with the majority (5 subjects) being newly diagnosed. Nineteen were found to have impaired glucose tolerance for a prevalence of 2.2%. There were no sex differences between the two groups. All of the newly diagnosed diabetics were asymptomatic. Multivariate analysis revealed that subjects with a family history of diabetes, higher body mass index, and higher systolic blood pressure had higher blood glucose levels. The prevalence of diabetes in this survey is lower than rates reported in recent surveys in Nigeria that used less stringent criteria and different methodologies. The rate is comparable to that of a Tanzanian study that used WHO criteria. However, the rate of impaired glucose tolerance in this study, first to be reported in Nigeria, is lower than that obtained in the Bantu population.