Motivational Interviewing Improves Weight Loss in Women with Type 2 Diabetes

Abstract

Objective: To determine whether adding motivational interviewing (MI) to a behavioral weight control program improves weight loss outcomes and glycemic control for overweight women with type 2 diabetes.

Research Design and Methods: A randomized, controlled clinical trial in which participants all received an 18-month, group-based behavioral obesity treatment and were randomized to individual sessions of motivational interviewing (MI) or attention control (total of 5 sessions) as an adjunct to the weight control program. Overweight women with type 2 diabetes treated by oral medications who could walk for exercise were eligible. Primary outcomes were weight and HbA1c assessed at 0, 6, 12 and 18 months.

Results: 217 overweight women (38% African American) were randomized (93% retention). Women in MI lost significantly more weight at 6-months (p=0.01) and 18- months (p=0.04). Increased weight losses with MI were mediated by enhanced adherence to the behavioral weight control program. African-American women lost less weight than white women overall and appeared to have a diminished benefit from the addition of MI. Significantly greater HbA1c reductions were observed in MI at 6-months (p=0.02) but not at 18-months.

Conclusions: MI can be a beneficial adjunct to behavioral obesity treatment for women with type 2 diabetes, although the benefits may not be sustained among African-American women.