Opioid use disorder and hospital readmission in the United States from 2010 to 2022: Primary reasons and the complex interplay of comorbid conditions.

Abstract

The opioid epidemic in the United States (U.S.) is a critical public health issue that has led to a sharp increase in opioid-related deaths, as well as significant implications for healthcare systems, including increased readmission rates. This study examines how opioid use disorder (OUD), when not the primary diagnosis, influences the risk of hospital readmission among other primary health condition groups. This retrospective study used data from the Nationwide Readmissions Database (NRD) from 2010 to 2022. Modified Poisson regression models were employed with Taylor-series linearization variance estimation to approximate relative risks (RRs) and 95% confidence intervals (CIs) to assess the association between secondary OUD status and all-cause, primary health condition (PHC)-specific, and substance use disorder (SUD)-specific readmission across five different PHCs (i.e., cardiovascular disease [CVD], respiratory disease [RD], mental health disorder [MHD], chronic pain [CP], and SUDs other than OUD). For all years and PHCs besides MHD and other SUDs, secondary OUD was associated with significantly higher risk of all-cause readmission (e.g. 2010 aRR [95% CI]: 1.19 [1.11, 1.27]; 2022 aRR [95% CI]: 1.10 [1.07, 1.14]). The risk of RD-specific and CP-specific readmission was significantly higher for patients with secondary OUD than those without. For all years and PHCs besides other SUDs, secondary OUD was associated with significantly higher risk of SUD-specific readmission. Secondary OUD was differentially associated with hospital readmission across PHCs, with added risk when accompanied by select comorbidities. Findings support condition-tailored discharge planning, OUD treatment linkage, addiction consultation, peer navigation, and post-discharge follow-up.