Objective: The effectiveness of the Peer-led Group Lifestyle Balance (PGLB) intervention, a 12-month manualized healthy lifestyle intervention delivered by peer specialists, was investigated in a sample of persons with serious mental illness who were overweight or obese and living in supportive housing.
Methods: The authors randomly assigned 314 participants from three supportive housing agencies to PGLB or usual care, with assessments at baseline and 6, 12, and 18 months. Outcomes were clinically significant changes from baseline in weight (≥5% weight loss), cardiorespiratory fitness (CRF; increase of ≥50 meters in the 6-minute walk test), and cardiovascular disease (CVD) risk reduction (clinically significant weight loss or CRF improvement).
Results: Most participants were from racial-ethnic minority groups (82%, N=255). The mean±SD baseline weight of this sample was 218.8±54.0 pounds, and the body mass index was 33.7±7.2. Compared with the usual care group, a larger proportion of the PGLB group achieved clinically significant changes in study outcomes at 12 and 18 months, but none of these changes was statistically significant. Outcomes differed by site: two sites reported no significant differences between the two groups, and one reported that PGLB significantly outperformed usual care on clinically significant weight loss at 18 months and CVD risk reduction at 6 and 12 months.
Conclusions: The null findings indicate that PGLB was not superior to usual care in helping participants achieve clinically significant changes in weight, CRF, and CVD risk reduction at 12 and 18 months. Questions remain regarding how PGLB works, for whom, and in which settings.
Trial registration: ClinicalTrials.gov NCT02175641.
Keywords: Healthy lifestyle intervention; Peer-delivered; Pragmatic trial; Serious mental illness; Supportive housing.