Motivational interviewing ineffective in helping patients lose weight

Reference

Michalopoulou M, Ferrey AE, Harmer G, et al. Effectiveness of motivational interviewing in managing overweight and obesity: a systematic review and meta-analysis. Ann Intern Med 2022;175(6):838-850.

Synopsis

These researchers searched 6 databases, including Cochrane CENTRAL, and 2 trial registries to identify randomized controlled trials published in any language that evaluated the use of motivational interviewing (MI) to help participants lose weight. The 46 studies of 11,077 participants (at least 12 years of age) compared MI with minimal intervention, a similar intensity non-MI intervention, or a lower intensity behavioral program that did not include MI. MI comprised written materials combined with counseling provided by psychologists, nurses, dietitians, or nutritionists. Most of the studies had a moderate to high risk of bias, either due to unclear randomization or dropouts. The researchers followed PRISMA guidelines for conducting and reporting the meta-analysis. At 6 months, MI was more slightly more effective than minimal intervention, producing an average weight loss of an additional 1 kg (standardized mean difference [effect size] -0.88; -1.27 to -0.48), but was no better than lower intensity or similar intensity interventions. At 1 year and beyond, there was no difference between lower and similar intensity interventions. There was high heterogeneity among the studies for most of the outcomes.