Factors associated with mortality following hospitalization among veterans with opioid use disorder

Hospitalizations are common among people with opioid use disorder (OUD). While hospitalizations represent opportunities to engage patients and offer treatment, they are also destabilizing events associated with an increased risk of death in the post-hospitalization period.

We conducted a retrospective cohort study within the Veterans Health Administration including all Veterans with OUD who experienced at least one medical hospitalization between January 2011 and December 2021. We examined which patient-level clinical and demographic factors were associated with all-cause and opioid-related mortality within 0-30 and 0-365 days following an index medical hospitalization.

The cohort included 90,920 Veterans with OUD who experienced one or more medical hospitalizations during the study period. Median age was 58 years, and 93 % were male. Older age (adjusted Odds Ratio [aOR] range 30d: 1.50-2.66; 1y: 1.58-3.28), higher medical complexity (aOR range 30d: 2.11-6.23; 1y: 1.96-7.34), multiple substance use disorders (SUD; aOR 30d: 1.81 (95 % CI 1.44, 2.27) 1y: 1.48 [95 % CI 1.36, 1.62]), and length of hospitalization (aOR 30d: 6.78 [95 % CI 4.85, 9.47] 1y: 3.45 [95 % CI 2.96, 4.01]) were associated with increased all-cause mortality following hospitalization. Homelessness (aOR 30d: 0.75 [95 % CI 0.63, 0.90]; 1y: 0.85 [95 % CI 0.80, 0.91]), depression (aOR 1y: 0.89 [95 % CI 0.84, 0.95]), bipolar disorder (aOR 1y: 0.88 [95 % CI 0.82, 0.94]), buprenorphine receipt (aOR 1y: 0.79 [95 % CI 0.69, 0.91]), and service connection (aOR 30d: 0.76 [95 % CI 0.60, 0.97] 1y: 0.64 [95 % CI 0.59, 0.70]) were associated with reduced all-cause mortality. Younger age (aOR range 30d: 3.21-5.24; 1y: 2.71-2.38), homelessness (aOR 1y: 1.40 [95 % CI 1.20, 1.63]), and multiple SUD (aOR 1y: 1.78 [95 % CI 1.33, 2.38]) were among factors associated with increased opioid-related mortality after hospitalization. Black race (aOR 1y: 0.61 [95 % CI 0.50, 0.74]) and higher service connection (aOR 30d: 0.41 [95 % CI 0.21, 0.81]; 1y: 0.53 [95 % CI 0.43-0.66]) were associated with reduced opioid-related mortality after hospitalization.

Several patient-level factors were associated with increased all-cause mortality (e.g., length of hospital stay), reduced all-cause mortality (e.g., homelessness), increased opioid-related mortality (e.g., multiple SUD), and reduced opioid-related mortality (e.g., service connection) after hospitalization. This information provides a roadmap for future development and study of tailored supports and risk stratification tools to enhance post-hospitalization transitional care for patients with OUD.