Does Type 2 Diabetes Genetic Testing and Counseling Reduce Modifiable Risk Factors? A Randomized Controlled Trial of Veterans

We examined the clinical utility of supplementing type 2 diabetes mellitus (DM) risk counseling with DM genetic test results and counseling. In this randomized controlled trial, non-diabetic overweight/obese veteran outpatients aged 21 to 65 years received DM risk estimates for lifetime risk, family history, and fasting plasma glucose, followed by either genetic test results (CR+G; N = 303) or control eye disease counseling (CR+EYE; N = 298). All participants received brief lifestyle counseling encouraging weight loss to reduce the risk of DM. The mean age was 54 years, 53% of participants were black, and 80% were men. There was no difference between arms in weight (estimated mean difference between CR+G vs. CR+EYE at 3 months = 0.2 kg, 95% CI: -0.3 to 0.7; at 6 months = 0.4 kg, 95 % CI: -0.3 to 1.1), insulin resistance, perceived risk, or physical activity at 3 or 6 months. Calorie and fat intake were lower in the CR+G arm at 3 months (p's a parts per thousand currency sign 0.05) but not at 6 months (p's > 0.20). Providing patients with genetic test results was not more effective in changing patient behavior to reduce the risk of DM compared to conventional risk counseling.