Diabetes and intermediate hyperglycaemia in Kisantu, DR Congo: a cross-sectional prevalence study

Objectives: To study the prevalence and risk markers of diabetes mellitus and intermediate hyperglycaemia (IH) in Kisantu, a semirural town in Bas-Congo province, The Democratic Republic of Congo. Design: A cross-sectional population-based survey. Settings: A modified WHO STEPwise strategy was used. Capillary glycaemia was measured for fasting plasma glucose and 2-h-postload glucose. Both WHO/IDF (International Diabetes Federation) 2006 and American Diabetes Association (ADA) 2003 diagnostic criteria for diabetes and IH were used. Participants: 1898 subjects aged >= 20 years. Results: Response rate was 93.7%. Complete data were available for 1759 subjects (86.9%). Crude and standardised (for Doll and UN population) prevalence of diabetes were 4.8% and 4.0-4.2%. Crude IH prevalence was 5.8% (WHO/IDF) and 14.2% (ADA). Independent risk markers for diabetes (p<0.01) were male (OR 2.5), age 50-69 years (OR 2.6), family history (OR 3.5), waist (OR 4.1) and alcohol consumption (OR 0.36). In receiver operating characteristic (ROC) analysis, prediction of diabetes was slightly better by waist than body mass index (BMI). IH defined according to WHO/IDF was associated with BMI (OR 2.6, p<0.001). IH defined according to ADA was associated (p<0.05) with waist (OR 1.4), education level (OR 1.6), BMI (OR 2.4) and physical activity (OR 0.7). Conclusions: Current prevalence of diabetes in DR Congo exceeds IDF projections for 2030. The lower glucose threshold used by ADA almost triples impaired fasting glucose prevalence compared to WHO/IDF criteria. The high proportion of disorders of glycaemia made up by IH suggests the early stages of a diabetes epidemic.