Effect of socioeconomic risk factors on the difference in prevalence of diabetes between rural and urban populations in Bangladesh

OBJECTIVE - To compare the prevalence of diabetes between the poor and rich of rural and urban populations in Bangladesh. RESEARCH DESIGN AND METHODS - A total of 1,052 subjects from urban and 1,319 from rural communities (age greater than or equal to 20 years) of different socioeconomic classes were investigated. Capillary blood glucose levels, fasting and 2 h after a 75-g glucose drink (2-h blood glucose [BG]), were measured. Height, weight, waist, hips, and blood pressure were also measured. RESULTS - Age-adjusted (30-64 years) prevalence of NIDDM was higher in urban (7.97% with 95% CI 6.17-9.77) than in rural subjects (3.84%, CI 2.61-5.07), whereas impaired glucose tolerance (IGT) prevalence was higher in rural subjects. In either urban or rural areas, the highest prevalence of NIDDM was observed among the rich, and the lowest prevalence was observed among the poor socioeconomic classes. The rural rich had much higher prevalence of IGT than their urban counterpart (16.5 vs. 4.4%, CI 6.8-17.4). Increased age was an important risk factor for IGT and NIDDM in both rural and urban subjects, whereas the risk related to higher BMI and waist-to-hip ratio (WHR) was less significant in rural than urban subjects. Using logistic regression and adjusting for age, sex, and social class, the urban subjects had no excess risk for NIDDM. In contrast, an excess risk for glucose intolerance (2-h BG greater than or equal to 7.8 mmol/1) was observed in the rural subjects. CONCLUSIONS - Adjusting for age, sex, and social class, the prevalence of NIDDM among urban subjects did not differ significantly from that among rural subjects. Increased age, higher socioeconomic class, and higher WHR were proven to be independent risk factors for glucose intolerance in either area.