Influence of residential greenness and season on discontinuation of medication treatment for opioid use disorder across rural to urban community types.

Introduction: Medications for opioid use disorder (MOUD) are standard of care for opioid use disorder (OUD), but high rates of treatment discontinuation limit their impact on recovery. Nature exposure and engagement holds promise as a potential adjunctive treatment to MOUD through stress reduction and mental health benefits. This study evaluated whether nature exposure influenced MOUD treatment participation by analyzing associations of residential greenness with MOUD discontinuation across a diverse geography in Pennsylvania, while considering interrelated factors-season and community type. Methods: We analyzed electronic health records from 2,570 adults receiving MOUD from an outpatient addiction treatment program. Weekly MOUD participation was derived from medication days' supply of buprenorphine or naltrexone. Average weekly greenness (normalized difference vegetation index) was assigned to buffers surrounding participants' residential address. We applied mixed-effects logistic regression of pooled person-weeks in treatment to model the odds of MOUD discontinuation, clustered by patient and with robust standard errors. Results: In models adjusted for sociodemographic factors, residential greenness was not associated with MOUD discontinuation. We observed associations of season with MOUD discontinuation: compared to spring weeks, the odds of MOUD discontinuation were 20-27% higher during summer, fall, and winter weeks. In season-stratified models, we observed a non-linear association of greenness and MOUD discontinuation during the spring season. Conclusions: Understanding factors contributing to MOUD discontinuation is essential to improving recovery outcomes for those with OUD. Findings suggest that passive greenness exposure may have little influence on MOUD participation but identified the potential importance of season on MOUD outcomes.