Care utilization among patients with stimulant use disorder during COVID-19: A national cohort study of U.S. Veterans

Abstract: Aim: Overdose rates have grown rapidly for both opioids and stimulants. However, much less is known about populations with stimulant use disorders (StUD), including those with comorbid opioid used disorder (OUD) and those without. In particular, no prior studies have comprehensively examined care utilization across both substance use disorder (SUD) treatment and inpatient hospitalizations, in particular since the start of the COVID-19 pandemic. Methods: This study examined all patients across the US in the Veterans Health Administration with StUD from 3/2020-2/2022. We compared patient characteristics among those diagnosed with StUD-only versus those with StUD+OUD. Using logistic regression models, we examined the association between comorbid OUD and receipt of SUD care (outpatient and residential) and inpatient medical and psychiatric care, adjusting for demographic and clinical characteristics. Results: Among the 123,228 Veterans with StUD from 3/2020-2/2022, 25,334 (20.6%) had a comorbid OUD. Among patients with StUD-only, 45.3% were Black, 7.2% female, 77.5% age ≥45, 45.1% homeless, 56.1% with comorbid alcohol use disorder, and 50.0% with depression compared to 25.1% Black, 7.9% female, 61.0% age ≥45, 38.2% homeless, 62.2% with alcohol use disorder, and 61.0% with depression among those with StUD+OUD. Among patients with StUD-only, 39.1% received any SUD care and 30.3% had ≥1 inpatient hospitalization compared to 61.7% (p<0.01) with SUD care and 35.9% (p<0.01) with an inpatient hospitalization among those with StUD+OUD. In regression models adjusting for all patient characteristics, Veterans with StUD+OUD were more likely to receive SUD care (AOR=2.14, 95%CI:2.08-2.21) and to have an inpatient hospitalization (AOR=1.12, 95%CI:1.09-1.16) compared to patients with StUD-only. Conclusions: In this national cohort of patients with StUD, only a minority of patients had comorbid OUD. However, both patients with and without comorbid OUD experienced high burden of comorbid conditions and high levels of care utilization including hospitalizations. New strategies are needed to mitigate harms across both groups of highly vulnerable and complex patients with StUD.