Do Differences in Waist Circumference Modify the Relationships Among Body Mass Index, Insulin Resistance, and Related Cardiometabolic Risk Factors in Apparently Healthy Women?

Objective: The aims of the study were to (1) compare the cardiometabolic risk profile between insulin-resistant and non-insulin-resistant women within similar body mass indexes (BMIs) and waist circumference (WC) groupings and (2) test the hypothesis that measurements of BMI are not inferior to WC in identifying insulin resistance. Methods: The sample consisted of 899 women without known cardiovascular disease or diabetes. BMI was used to divide participants in normal (<25.0 kg/m2), overweight (≥25–29.9 kg/m2), and obese (≥30.0 kg/m2) subgroups, and waist circumference ≥88 cm was used to identify women with or without abdominal obesity. The 25% of the population with highest fasting insulin concentrations was classified as insulin resistant. BMI, WC, blood pressure, and fasting plasma glucose, insulin, triglyceride, and high-density lipoprotein cholesterol concentrations were compared using analysis of covariance (ANCOVA). The relationships between obesity and insulin resistance were analyzed using univar...