Random capillary blood sugar and coronary risk factors in a south Kerala population.

Background: High prevalence of type 2 diabetes in one subdivision of a district in south India prompted us to look at the prevalence of other major coronary risk factors, and relate these to random blood sugar values.

Design: Cross-sectional survey of all adult residents of four wards (clusters of households) of a subdivision. Detailed investigation for diabetes and blood lipids in a selected subsample with random blood sugar (RBS) >109 mg/dl by glucometer.

Methods: From the selected wards, we conducted a standard oral glucose tolerance test and serum lipids in all those who had RBS above 109 mg/dl by glucometer. Risk factors such as smoking, obesity (body mass index > 29.9), high blood pressure (systolic pressure > 139; diastolic pressure > 89 mmHg) and sedentary habits were assessed in all irrespective of RBS.

Results: Prevalence of all risk factors increases with age. Mean RBS ranges from 92.9 +/- 15.7 to 108.8 +/- 35.7 mg/dl in males and 88.6 +/- 16.0 to 117.3 +/- 61.6 mg/dl in females, between the age groups 20-29 to > 69. Risk factor prevalence varied with area of residence, with urban population reporting highest prevalence for type 2 diabetes and obesity, and coastal population for hypertension. For increasing levels of fasting plasma glucose (FPG < 100, 100-124 and > 125 mg/dl), serum total cholesterol values were 5.21 +/- 1.08 mM/l, 5.38 +/- 0.86 mM/l and 5.63 +/- 1.37 mM/l for males. For females, corresponding values were 5.23 +/- 1.11 mM/l, 5.54 +/- 1.15 mM/l, and 5.49 +/- 1.10 mM/l respectively.

Conclusions: Risk factor prevalence varies with area of residence within the study population. Mean plasma lipid levels are high among both sexes, tending to rise with increasing mean fasting plasma glucose levels.