Impact of poverty on the prevalence of diabetes and its complications in urban southern India

AIM: The impact of poverty on the profile of diabetes and its complications was studied. METHODS: A comparative study of low income group (LIG) (family income Rs. < 30,000/annum (approx. 432 pounds sterling) and high income group (HIG) (family income Rs. greater-than-or-equal 60,000/annum (approx. pounds sterling) subjects of > or = 40 years was done in Madras, India. By screening 1748 LIG subjects (M/W 844/904) 301 diabetic subjects were identified and 218 underwent tests for diabetic complications. Population data available in 635 (M/W 309/326) HIG subjects from the survey were used for comparison of glucose tolerance profile. Complications were studied in 221 diabetic HIG subjects. RESULTS: Age-standardized prevalences of diabetes (12.6% vs. 25.5%; chi(2) = 56.9, P < 0.0001) and impaired glucose tolerance (IGT) (8.9% vs. 19.0%) were significantly lower (chi(2) = 57.7; P < 0.0001) in the LIG. Hypertension was more common in LIG (53.7% vs. 40.0% in HIG; chi(2) = 34.9; P < 0.0001). LIG subjects were more physically active; 73.8% did not go to school. Parameters significantly associated with diabetes were body mass index (BMI), age, higher income, waist--hip ratio and physical inactivity. Higher income, BMI and age were associated with IGT. Diabetic LIG subjects had a higher prevalence of cardiac disease, neuropathy and cataract and a lower prevalence of retinopathy than HIG subjects. The risk variables such as hyperglycaemia, dyslipidaemia, hypertension, smoking and alcohol consumption were more in the LIG group. CONCLUSIONS: The urban poor in the developing world has a lower prevalence of diabetes than the urban poor in developed societies. However, they have higher rates of complications of diabetes.