Insulin, body mass index, and cardiovascular risk factors in premenopausal women.

This study assessed the relationship between insulin, glucose, body mass index, and cardiovascular risk factors in a sample of 489 white premenopausal women. All women were participants in the Healthy Women Study (University of Pittsburgh) and had normal blood pressure and fasting blood glucose of less than 140 mg/dl and a 2-hour value after a 75-g glucose load of less than 200 mg/dl. Both body mass index and fasting insulin were significantly and independently associated with blood pressure, triglycerides, and high density lipoprotein (HDL) cholesterol and its subfractions. Body mass index and fasting insulin were more strongly associated with coronary heart disease (CHD) risk factors than were 2-hour insulin, or fasting or 2-hour glucose; glucose levels did not contribute independently to multivariate predictions of any of the CHD risk factors. When patients were divided into tertiles according to fasting insulin and body mass index, there were significant main effects of insulin and body mass index on blood pressure, triglycerides, and HDL cholesterol and its subfractions; the interaction of insulin times body mass index was also significant for systolic blood pressure, triglycerides, and apoprotein B. These data confirm the previous findings of a strong association between insulin and CHD risk factors and extend this to healthy premenopausal women.