Fasting glucose and cardiovascular risk factors in an urban population.

OBJECTIVE: To test the hypothesis that blood glucose levels in the range of normoglycemia are associated with increased cardiovascular risk we performed an epidemiological study in an urban population.

METHODS: Randomly selected adults > or = 20 years were studied using stratified sampling. Target sample was 1800 (men 960, women 840) of which 1123 subjects participated. Blood samples were available in 1091 subjects (60.6%, men 532, women 559). Measurement of anthropometric variables, blood pressure, fasting blood glucose and lipids was performed. Cardiovascular risk factors were determined using US Adult Treatment Panel-3 guidelines. Pearson's correlation coefficients (r) of fasting glucose with various risk factors were determined. Fasting glucose levels were classified into various groups as < 75 mg/dl, 75-89 mg/dl, 90-109 mg/dl, 110-125 mg/dl and > 126 mg/dl or known diabetes. Prevalence of cardiovascular risk factors was determined in each group.

RESULTS: There was a significant positive correlation of fasting glucose in men and women with body mass index (r = 0.20, 0.12), waist-hip ratio (0.17, 0.09), systolic blood pressure (0.07, 0.22), total cholesterol (0.21, 0.15) and triglycerides (0.21, 0.25). Prevalence (%) of cardiovascular risk factors in men and women was smoking/tobacco use in 37.6 and 11.6, hypertension in 37.0 and 37.6, overweight and obesity in 37.8 and 50.3, truncal obesity in 57.3 and 68.0, high cholesterol > or = 200 mg/dl in 37.4 and 45.8, high triglycerides > or = 150 mg/dl in 32.3 and 28.6 and metabolic syndrome in 22.9 and 31.6 percent. In various groups of fasting glucose there was an increasing trend in prevalence of overweight/obesity, hypertension, hypercholesterolaemia, hypertriglyceridaemia, and metabolic syndrome (Mantel-Haenzel X2 for trend, p < 0.05) and fasting glucose < 75 mg/dl was associated with the lowest prevalence of these risk factors.

CONCLUSIONS: There is a continuous relationship of fasting glucose levels with many cardiovascular risk factors and level < 75 mg/dl is associated with the lowest prevalence.