Abstract

Objective: To determine the prevalence of diabetes mellitus, impaired glucose tolerance (IGT) and impaired fasting glycaemia (IFG) and associated risk factors in a rural South African Black community.

Research Design and Methods: A cross-sectional survey conducted by random cluster sampling of adults >15 years. Participants had a 75g OGTT using 1998 World Health Organisation (WHO) criteria for disorders of glycaemia.

Results: Of 1300 subjects selected, 1025 subjects (women: 815) participated (response rate 78.9%). The overall age-adjusted prevalence of diabetes was 3.9%, of IGT 4.8% and of IFG 1.5%. The prevalence was similar in men and women for diabetes (M: W; 3.5: 3.9%) and IGT (M: W; 4.6%: 4.7%) but higher in men for IFG (M: W; 4.0%: 0.8%). The prevalence of diabetes and IGT increased with age both in men and women, with peak prevalence in the 55-64 yr age-group for diabetes and in the ≥ 65 year age-group for IGT. Of the subjects with diabetes, 84.8% were discovered during the survey.

Results: In multivariate analysis, the significant independent risk factors associated with diabetes included family history (OR3.5), alcohol ingestion (OR2.8), waist circumference (OR1.1), systolic blood pressure (OR1.0), serum triglycerides (OR2.3) and total cholesterol (OR1.8); hip circumference was protective (OR0.9).

Conclusion: There is a moderate prevalence of diabetes and high prevalence of total disorders of glycaemia and suggests that this community unlike other rural communities in Africa is well into the epidemic of glucose intolerance. There is a low proportion of known diabetes and significant association with potentially modifiable risk factors.