Background: Inconsistent findings have been reported regarding improved health-related quality of life (HRQOL) after weight loss. We tested the efficacy of a weight management program for improving HRQOL in overweight or obese adults diagnosed as having type 2 diabetes mellitus.
Methods: We conducted a randomized multisite clinical trial at 16 outpatient research centers with 2 treatment arms and blinded measurements at baseline and the end of year 1. A total of 5145 participants (mean [SD] age, 58.7 [6.9] years; mean [SD] body mass index [calculated as weight in kilograms divided by height in meters squared], 36.0 [5.9]; 59.5% women; 63.1% white) were randomized to an intensive lifestyle intervention (ILI) or to diabetes support and education (DSE). Main outcome measures included the 36-Item Short-Form Health Survey physical component summary (PCS) and mental health component summary (MCS) scores and Beck Depression Inventory II (BDI-II) scores. Baseline mean (SD) scores were 47.9 (7.9) for PCS, 54.0 (8.1) for MCS, and 5.7 (5.0) for BDI-II.
Results: Improved HRQOL was demonstrated by the PCS and BDI-II scores (P < .001) in the ILI arm compared with the DSE arm. The largest effect was observed for the PCS score (difference, -2.91; 99% confidence interval, -3.44 to -2.37). The greatest HRQOL improvement occurred in participants with the lowest baseline HRQOL levels. Mean (SD) changes in weight (ILI, -8.77 [8.2] kg and DSE, -0.86 [5.0] kg), improved fitness, and improved physical symptoms mediated treatment effects associated with the BDI-II and PCS.
Conclusions: Overweight adults diagnosed as having type 2 diabetes experienced significant improvement in HRQOL by enrolling in a weight management program that yielded significant weight loss, improved physical fitness, and reduced physical symptoms.
Trial registration: clinicaltrials.gov Identifier: NCT00017953.