2019 HSR&D/QUERI National Conference

4070 — Comorbid substance use disorders in Veterans with opioid use disorder: the association with treatment receipt

Lead/Presenter: Lewei (Allison) Lin,  COIN - Ann Arbor
All Authors: Lin L (Center for Clinical Management Research, VA Ann Arbor Healthcare System and Dept. of Psychiatry, University of Michigan), Ilgen MA (Center for Clinical Management Research, VA Ann Arbor Healthcare System and Dept. of Psychiatry, University of Michigan), Gordon AJ (VA Informatics, Decision Enhancement and Analytic Sciences Center, Salt Lake City VA Healthcare System and University of Utah School of Medicine) Ignacio RV (Center for Clinical Management Research, VA Ann Arbor Healthcare System and Dept. of Psychiatry, University of Michigan( Bohnert AS (Center for Clinical Management Research, VA Ann Arbor Healthcare System and Dept. of Psychiatry, University of Michigan)

Objectives:
Opioid use disorder (OUD) in Veterans is associated with serious harms including overdose and suicide. However, only a third of Veterans receive buprenorphine and methadone treatment, which help prevent these harms. Comorbid diagnoses of other substance use disorders (SUDs) can impact clinicians' willingness to use these medications. However, little is known about comorbid SUDs among Veterans with OUD and impacts on treatment.

Methods:
This study examined the cohort of Veterans nationally with OUD in FY2017. We compared patient characteristics among those diagnosed with OUD only with those with one other SUD (OUD+1 SUD) and with multiple SUDs (OUD+?2 SUDs). We examined the relationship between comorbid SUDs and receipt of buprenorphine, methadone and SUD clinic treatment during one year follow-up, adjusting for demographics and clinical conditions.

Results:
Among the 65,741 Veterans with OUD in FY2017, 41.2% had OUD only, 22.9% had OUD+1 SUD, and 35.9% had OUD+?2 SUDs. Common comorbid SUDs included alcohol use disorder (41.3%), cocaine/stimulant use disorder (30.0%) and cannabis use disorder (22.3%). Adjusting for baseline characteristics, Veterans with OUD+1 SUD (AOR = 0.90, 95% CI:0.86-0.95) and Veterans with OUD+?2 SUDs (AOR = 0.69, 95% CI:0.65-0.73) were less likely to receive buprenorphine compared to OUD only patients. There were no significant differences in methadone for Veterans with OUD+1 SUD (AOR = 1.00, 95% CI:0.95-1.06) and modest differences for those with OUD+?2 SUDs (AOR = 0.91, 95% CI:0.86-0.96). Veterans with OUD+1 SUD (AOR = 1.91, 95% CI:1.83-1.99) and Veterans with OUD+?2 SUDs (AOR = 3.38, 95% CI:3.23-3.54) were more likely to have a SUD clinic visit.

Implications:
The majority of Veterans with OUD have at least one comorbid SUD and many have multiple SUDs. Despite higher likelihood of a SUD clinic visit, having an additional SUD is associated with lower likelihood of buprenorphine treatment, potentially due to provider uncertainty about medication treatment in patients with comorbid SUDs.

Impacts:
Additional efforts are needed to understand barriers to medication treatment for the majority of Veterans with OUD who have comorbid SUDs. These results emphasize the importance of addressing comorbid SUDs within current efforts to expand medication treatment access for OUD.