Sharon Reif, Andrea Acevedo, Deborah W Garnick, Catherine A Fullerton

Individuals with substance use disorders are at high risk of hospital readmission. This study examined whether follow-up services received within 14 days of discharge from an inpatient hospital stay or residential detoxification reduced 90-day readmissions among Medicaid enrollees whose index admission included a substance use disorder diagnosis. Claims data were analyzed for Medicaid enrollees ages 18-64 with a substance use disorder diagnosis coded in any position for an inpatient hospital stay or residential detoxification in 2008 (N=30,439). Follow-up behavioral health services included residential, intensive outpatient, outpatient, and medication-assisted treatment (MAT). Analyses included data from ten states or fewer, based on a minimum number of index admissions and the availability of follow-up services or MAT. Survival analyses with time-varying independent variables were used to test the association of receipt of follow-up services and MAT with behavioral health readmissions. Two-thirds (67.7%) of these enrollees received no follow-up services within 14 days. Twenty-nine percent were admitted with a primary behavioral health diagnosis within 90 days of discharge. Survival analyses showed that MAT and residential treatment were associated with reduced risk of 90-day behavioral health admission. Receipt of outpatient treatment was associated with increased readmission risk, and, in only one model, receipt of intensive outpatient services was also associated with increased risk. Provision of MAT or residential treatment for substance use disorders after an inpatient or detoxification stay may help prevent readmissions. Medicaid programs should be encouraged to reduce barriers to MAT and residential treatment in order to prevent behavioral health admissions.