Characteristics and co-morbidities associated with hospital discharges for opioid and methamphetamine co-use, United States 2016-2019.

Introduction: The US overdose crisis is increasingly characterized by opioid and methamphetamine co-use. Hospitalization is an important opportunity to engage patients in substance use treatment. Understanding characteristics of co-use-related hospital stays can inform the development of services to better support this growing patient population. Methods: We used 2016-2019 National Inpatient Sample data to conduct a cross sectional analysis of hospitalizations involving use of opioids, methamphetamine, or both. We used bivariate analysis to compare patient demographics. We then used multinomial logistic regressions to compare the proportion of hospital stays which indicated co-morbid diagnosis. To account for correlated data, we used generalized linear models to compare outcomes in hospital mortality, patient-directed discharge, and length of stay. Results: Co-use-related stays had a higher proportion of co-morbid mental health (60.7%; 95% CI: 59.9-61.4%) and infectious diseases (41.5%; 95% CI: 40.8-42.2%), than opioid- or methamphetamine-related stays. Co-use-related stays increased between 2016 and 2019 and were associated with a higher proportion of patient directed discharge (10.7%; 95% CI: 10.4-11.0%) and longer length of stay (6.3 days; 95% CI: 6.2-6.4 days) compared to opioid (8.1%; 95% CI: 7.9-8.3% and 5.8 days; 95% CI: 5.8-5.9 days) and methamphetamine-related stays (6.5%; 95% CI: 6.3-6.6% and 5.5 days; 95% CI: 5.4-5.5 days). Conclusion: Patients discharged with co-use differ from patients with opioid or methamphetamine use alone, representing a range of challenges and opportunities. In addition to offering treatment for both substance use disorders, hospital-based services that address co-occurring conditions may better support patients with co-use through targeted and tailored approaches.