Yoga MAT: A factorial randomized study using the Multiphase Optimization Strategy to develop a multicomponent yoga intervention for people with chronic pain taking medications for opioid use disorder.

BACKGROUND: People taking medications for opioid use disorder (MOUD) commonly experience chronic pain. Yoga interventions show promise for decreasing pain-related disability in other populations. More time spent in yoga practice may improve pain-related outcomes. METHODS: The Multiphase Optimization Strategy (MOST) provided the framework for developing an optimized yoga intervention package. In a 2x2x2x2 factorial experiment, we evaluated four candidate intervention components which, when added to a weekly yoga class, might increase yoga engagement. The primary outcome was minutes per week of yoga practice (classes and other yoga practice) over the 12-week intervention period. We sought to determine which combination of intervention components was associated with the most yoga practice for people with chronic pain taking buprenorphine or methadone as MOUD. RESULTS: We enrolled 192 adults. There was a significant main effect for Component "B" (having two private sessions with a yoga teachers; IRR = 1.10, 90%CI 1.02; 1.18), and a synergistic interaction between Components "B" and "D" (D was financial incentives for attending class; IRR = 1.11, 90%CI 1.02; 1.19). This combination of these two components (without other potential components) was associated with the second highest model-predicted mean minutes of yoga per week (157.1min; 90% CI = 120.1-194.0) which was only 4min less than the combination including all four components. CONCLUSIONS: We identified a combination of intervention components as the optimized intervention. A next step will be to test the effect of this optimized intervention on pain and substance use outcomes in a randomized controlled clinical trial.