The interrelationship between impaired glucose tolerance and other risk factors for cardiovascular disease: is it a predictor for cardiovascular disease?

Glucose intolerance and cardiovascular risk factors were assessed among 215 subjects aged 27-86 years in Ho-long, Taiwan. An oral glucose tolerance test (OGTT) was normal in 107 subjects, impaired in 41 subjects, and abnormal in 67 subjects (as noninsulin dependent diabetes mellitus, NIDDM). Body fatness, blood pressure, carbohydrate and lipid metabolic factors were examined. One-way ANCOVA was used to compare age- and/or BMI-adjusted differences among these groups. Male subjects with NIDDM and impaired glucose tolerance (IGT) had higher systolic (SBP) and diastolic (DBP) blood pressures, plasma insulin (fasting and 1-hour after OGTT), serum triglycerides (TG), heavier body weight, and larger BMI than normal. IGT subjects were also found to have higher TG, insulin (2-hour) and larger insulin area under curve (IAUC) after OGTT than NIDDM. In females, subjects with NIDDM had higher TG, insulin (fasting and 1-hour after OGTT), and larger IAUC than normal. Moreover, female IGT subjects were also found to have significantly higher SBP, DBP, insulin (1-and 2-hour after OGTT), and larger IAUC than both normal and NIDDM subjects. These results suggest that adverse cardiovascular risk factors are present not only in NIDDM subjects, but also in IGT subjects.