Cardiovascular risk factors and impaired glucose tolerance: the San Luis Valley Diabetes Study

Cardiovascular risk factor patterns were examined cross-sectionally in 856 Hispanic and Anglo subjects aged 20-74 years enrolled in the population-based San Luis Valley Diabetes Study of Colorado. Risk factor levels and prevalence were compared for 279 individuals with non-insulin-dependent diabetes mellitus, 89 with impaired glucose tolerance, and 488 with normal glucose tolerance. Sex-specific comparisons of continuous risk factors were made by diabetic status and ethnicity, adjusting for age using two-way analysis of covariance; similar comparisons of discrete variables were made using logistic regression. A number of vascular, metabolic, lipid, obesity-related, family history, and life-style risk factors for cardiovascular disease were examined. In general, biologic risk factors tended to be more strongly associated with diabetic status, while life-style risk factors varied more by ethnicity. Age-adjusted levels of systolic and diastolic blood pressure, hypertension history, triglyceride, and body mass index were lowest among normal subjects, intermediate for those with impaired glucose tolerance, and highest in subjects with non-insulin-dependent diabetes mellitus, while the trend was reversed for high density lipoprotein (HDL) cholesterol and its subfractions. Hispanics had lower serum uric acid levels and greater central obesity than Anglos; they were less likely to have a Type A personality, less physically active at work, and more likely to be a current smoker than Anglos. Hispanic males had a lower body mass index and a higher HDL cholesterol level than Anglo males. These results indicate that an adverse cardiovascular risk factor pattern is present not only in subjects with non-insulin-dependent diabetes mellitus but also in subjects with impaired glucose tolerance who are at increased risk of developing diabetes. This suggests that an adverse risk factor pattern may develop concurrently with or prior to the onset of impaired glucose tolerance. Future prospective studies will help to clarify the temporal sequence involved in the development of adverse cardiovascular risk factor patterns and impaired glucose tolerance.