Sex differences in diabetes risk and the effect of intensive lifestyle modification in the Diabetes Prevention Program

Abstract

Objective: In participants of the Diabetes Prevention Program (DPP) randomized to intensive lifestyle modification (ILS), meeting ILS goals was strongly correlated to prevention of diabetes in the group as a whole. Men, however, met significantly more ILS goals than women, but had a similar incidence of diabetes. Therefore, we explored sex differences in risk factors (RFs) for diabetes, and the effect of ILS on RFs.

Research Design And Methods: Baseline RFs for diabetes, and percent change in RFs over the first year, were compared using Wilcoxon rank-sums in men vs. women.

Results: At baseline, men were older, had a larger waist circumference, higher fasting plasma glucose concentration, caloric intake, and blood pressure, as well as lower HDL cholesterol and corrected insulin response than women, who were less physically active and had a higher body mass index (BMI) (p<0.01 for all comparisons). Over the first year of DPP, no sex difference in RFs for diabetes was observed for those who lost <3% body weight. Weight loss of 3-7% yielded greater decreases in 2-hour glucose (p<0.01), insulin concentration (p<0.04) and insulin resistance (p<0.03) in men vs. women. Weight loss of >7% resulted in greater decreases in 2-hour glucose (p<0.01), triglyceride level (p<0.01) and HbA1C (p<0.03) in men vs. women.

Conclusions: Weight loss >3% yielded greater reduction in RFs for diabetes in men vs. women. Despite the more favorable effects of ILS in men, baseline RFs was more numerous in men, and likely obscured any sex difference in incident diabetes.