Utilization of Outpatient and Intensive Treatment Services By Adults with Multiple Substance Use Disorders in the Medicaid Population
Authors: O'Brien P. , Creedon T. , Lin J. , Schaefer M. E. , Henke R. 
Published: August 2020

Research Objective

Use of multiple substances is common among adults who misuse opioids. Adverse consequences of drugs are more severe among multisubstance relative to single drug users. It is not known whether adults with multiple substance use disorders (multi‐SUD) including opioid use disorder (OUD) receive treatment at the same level compared with those with OUD only. If not, additional emphasis in interventions may be needed to target this population. This study sought to (1) assess whether adults with multi‐SUD are as likely to receive outpatient or intensive treatment compared with adults with OUD only and (2) determine whether any particular drug use combinations are at risk for not receiving treatment.

Study Design

We conducted a retrospective longitudinal study using IBM® MarketScan® Multi‐State Medicaid Database enrollment and claims data (2016‐2017). We used adjusted logistic regression to measure the association between clinical characteristics and receipt of treatment.

Population Studied

The sample included non‐Medicare‐eligible adults aged 18‐64 years who were continuously enrolled in Medicaid and had at least one claim in 2016 with a primary OUD diagnosis.

Principal Findings

Of the 58,745 Medicaid enrollees with an initial OUD diagnosis in 2016, 29,478 had no other SUDs. The remaining 29,267 had additional SUD diagnoses. In the year following diagnosis, adults with multi‐SUD were less likely to receive OUD outpatient services or medication treatment than adults with OUD only (OR = 0.931, P = .0006). Adults with co‐occurring alcohol (OR = 0.774, P < .0001), cannabis (OR = 0.848, P < .0001), or stimulant (OR = 0.829, P < .0001) disorder were significantly less likely to receive OUD outpatient treatment than adults with OUD only. Adults with a co‐occurring sedative, hypnotic, or anxiolytic use disorder (SHA) were the only group meaningfully more likely to receive OUD outpatient treatment (OR = 1.179, P < .0001).

Adults with multi‐SUD were more likely to use all types of higher intensity services than those with OUD only. Other than for detoxification services, individuals with OUD and a cocaine use disorder were most likely to experience all‐cause use of intensive treatment services. Individuals with OUD and alcohol use disorder were most likely to receive detoxification services (OR = 2.260, P < .0001). Individuals with co‐occurring SHA and OUD used inpatient, emergency department, residential, and detoxification services more heavily compared with other multi‐SUD combinations.

Only adults with co‐occurring SHA and OUD used outpatient mental health services and medication to a larger extent than those with OUD only. Those with OUD and a stimulant use disorder were significantly less likely to use such services (OR = 0.937, P = .0105).

Conclusions

Our findings suggest that there are barriers to outpatient OUD and mental health treatment for adults with multi‐SUD. Adults with co‐occurring alcohol, cannabis, and stimulant misuse are particularly at risk for not receiving services. Adults with multi‐SUD receive more intensive services, which may reflect severity and lack of outpatient treatment before misuse escalation. Intensive services are expensive and should be provided along with outpatient OUD treatment to be most effective.

Implications for Policy or Practice

Programs should account for barriers in connecting people with multi‐SUD to OUD treatment and implement best practices for treatment of non‐OUD SUDs.

Primary Funding Source

SAMHSA.