Medication costs during an 18 month clinical trial of obesity treatment among patients encountered in primary care

BACKGROUND: Weight loss often leads to reductions in medication costs, particularly for weight-related conditions. We aimed to evaluate changes in medication costs from an 18 month study of weight loss among patients recruited from primary care. METHODS: Study participants (n = 79, average age = 56.3; 75.7 % female) with average BMI of 39.5 kg/m(2), plus one co-morbid condition of either diabetes/pre-diabetes, hypertension, abnormal cholesterol, or sleep apnea, were recruited from 2 internal medicine practices. All participants received intensive behavioral and dietary treatment during months 0–6, including subsidized access to portion-controlled foods for weight loss. From months 7–18, all participants were offered continued access to subsidized foods, and half of participants were randomly assigned to continue in-person visits (“Intensified Maintenance”), while the other half received materials by mail or e-mail (“Standard Maintenance”). Medication costs were evaluated at months 0, 6, and 18. RESULTS: Participants assigned to Intensified Maintenance maintained nearly all their lost weight, whereas those assigned to Standard Maintenance regained weight. However, no significant differences in medication costs were observed within or between groups during the 18 months of the trial. A reduction of nearly $30 per month (12.9 %) was observed among all participants from month 0 to month 6 (active weight loss phase), but this difference did not reach statistical significance. CONCLUSIONS: A behavioral intervention that led to clinically significant weight loss did not lead to statistically significant reductions in medication costs. Substantial variability in medication costs and lack of a systematic approach by the study team to reduce medications may explain the lack of effect. TRIAL REGISTRATION: The trial was registered at (NCT01220089) on September 23, 2010.