Prevalence and correlates of diabetes mellitus in Malawi: population-based national NCD STEPS survey

BACKGROUND: Previously considered as a disease of the affluent, west or urban people and not of public health importance, diabetes mellitus is increasingly becoming a significant cause of morbidity and mortality in sub-Saharan Africa. However, population-based data to inform prevention, treatment and control are lacking. METHODS: Using the WHO STEPwise approach to chronic disease risk factor surveillance, a population-based, nationwide cross-sectional survey was conducted between July and September 2009 on participants aged 25-64 years. A multi-stage cluster sample design and weighting were used to produce a national representative data for that age range. Detailed findings on the magnitude of diabetes mellitus and impaired fasting blood glucose are presented in this paper. RESULTS: Fasting blood glucose measurement was conducted on 3056 participants (70.2% females, 87.9% from rural areas). The age- sex standardised population-based mean fasting blood glucose was 4.3 mmol/L (95% CI 4.1-4.4 mmol/L) with no significant differences by age, sex and location (urban/rural). The overall prevalence of impaired fasting blood glucose was 4.2% (95% CI 3.0%-5.4%). Prevalence of impaired blood glucose was higher in men than in women, 5.7% (95% CI 3.9%-7.5%) vs 2.7% (95% CI 1.6%- 3.8%), p 0.05. Compared to previous estimates, prevalence of diabetes increased from <1.0% in 1960s to 5.6% in 2009 (this study). CONCLUSION: High prevalence of impaired fasting blood glucose and diabetes mellitus call for the implementation of primary healthcare approaches such as the WHO package for essential non-communicable diseases to promote healthy lifestyles, early detection, treatment and control.