First-Year Economic and Quality of Life Effects of the RAINBOW Intervention to Treat Comorbid Obesity and Depression

Objective Obesity and depression are prevalent and often co-occurring conditions in the United States. The Research Aimed at Improving Both Mood and Weight (RAINBOW) randomized trial demonstrated the effectiveness of an integrated intervention for adults with both conditions. Characterizing the intervention's economic effects is important for broader dissemination and implementation. Methods This study evaluated the cost (2018 US dollars) and health-related quality of life (HRQoL) impacts during RAINBOW's first year, comparing intervention (n = 204) and usual-care groups (n = 205). Outcomes included intervention delivery costs, differential changes in antidepressant medication spending compared with the pretrial year, differential changes in medical services spending compared with the pretrial year, and HRQoL changes from baseline using Euroqol-5D US utility weights. Results RAINBOW's 1-year delivery cost per person was $2,251. Compared with usual care, annual antidepressant medication days increased more (38 days [95% CI: 4 to 72]; P = 0.027). Annual antidepressant medication spending had a larger, nonsignificant increase ($89 [95% CI: -$20 to $197]; P = 0.109). Annual spending on medical care services had a smaller, nonsignificant decrease (-$54 [95% CI: -$832 to $941]; P = 0.905). HRQoL had a nonsignificant increase (0.011 [95% CI: -0.025 to 0.047]; P = 0.546). Conclusions The RAINBOW intervention's economic value will depend on how its 1-year improvements in obesity and depression translate into long-term reduced morbidity, delayed mortality, or averted costs.