Polysubstance use and post-discharge mortality risk among hospitalized patients with opioid use disorder.

Polysubstance use is becoming increasingly common and presents several harms. This study aimed to examine the association of comorbid cocaine, alcohol (binge drinking), and sedative use with mortality among hospitalized patients with opioid use disorder (OUD). A subsample of adult medical/surgical hospital patients with OUD who were seen by a hospital addiction consultation service in Baltimore City and enrolled in a randomized trial of a patient navigation intervention were included in this study (N = 314; 45 % female; 48 % White; mean age = 44). Death certificate data from the Maryland Division of Vital Records was used, covering 3.3-5.5 years post-discharge. Multivariable proportional hazards Cox regression and competing risks regression were used to estimate all-cause mortality and overdose mortality, respectively, as a function of concurrent use of cocaine, alcohol (binge drinking), and non-prescribed sedatives at baseline. In the 30 days prior to hospital admission, 230 (73 %) participants used cocaine, 64 (20 %) binge drank, and 45 (14 %) used non-prescribed sedatives. Nearly one-third (N = 98; 31 %) died during the observation period. Drug overdose caused 53 % (N = 52) of deaths. Older age (HR = 1.03 [1.01,1.05]; P = 0.001), less than high school education (HR = 0.36 [0.24,0.54]; P < 0.001), and past 30-day sedative use (HR = 2.05 [1.20,3.50]; P = 0.008) were significantly associated with all-cause mortality. The risk of overdose mortality was 62 % lower (HR = 0.38 [0.22,0.66]; P = 0.001) for those who completed high school. No other characteristics were significantly associated with overdose mortality. The concurrent use of opioids and sedatives increases the post-discharge mortality risk among hospitalized patients with OUD. Interventions are needed to prevent mortality among this high-risk population.