Effect of managed care on access to mental health services among Medicaid enrollees receiving substance treatment.

Objective: Mental health services are important to treatment retention and positive outcomes for many clients of substance abuse treatment programs. For these clients the implementation of managed care should provide for continued or increased access to mental health treatment, rather than decreased access because of short-term, cost-reduction objectives. This study assessed whether converting Medicaid from a fee-for-service program to a capitated, prepaid managed care program affected access to mental health services among clients who were treated for substance abuse.

Methods: Medicaid enrollees who were being treated for substance abuse in Oregon were interviewed before beginning treatment and after six months of service. One cohort (N=53) was interviewed one to six months before the implementation of managed care, a second (N=66) was interviewed two years after the implementation, and a third (N=49) was interviewed three to four years after the implementation. Logistic regression analyses were used to identify whether the implementation of managed care, the psychiatric need of the client, and other client characteristics affected the receipt of mental health services during the first six months of substance abuse treatment.

Results: Clients in all three cohorts had similar characteristics. The implementation of managed care did not affect whether clients received mental health services. A baseline interview score that was derived from items in the Addiction Severity Index psychiatric section was the only client characteristic that predicted receipt of mental health services.

Conclusions: Although this study was a naturalistic experiment with many methodologic flaws, it provided a unique opportunity to observe whether the introduction of managed care changed access to mental health services among Medicaid enrollees who were being treated for substance abuse.