Effects of Patient Copayments on Retention in Substance Abuse and Mental Health Treatment

Rationale: In the US, many health plans and managed behavioral health care organizations (MBHOs) require patient copayments at each visit, following the model they use for medical care. Prior research has shown that higher cost-sharing results in lower utilization of substance abuse and mental health care. However, some plans provide the first few visits free, with copayments only for subsequent visits. It is not known how utilization is affected by this type of 'stepped' cost-sharing, which might encourage treatment retention by removing one potential barrier during the early phase when patients may be particularly vulnerable to dropout. Objectives: To study the effect of copayment level, and stepped copayments on the distribution of the number of visits per user of substance abuse and mental health treatment. Data: We take advantage of natural variation among insured groups in a single MBHO. Some employers purchase an insurance product where behavioral health benefits are 'integrated' with an employee assistance plan (EAP). As a result, the first few visits are provided free of charge to the patient, under the EAP benefit. The number of free visits varies somewhat across employers. Other employers purchase the 'stand-alone' product with copayments for all visits. Even when copayments are charged, the level varies across employers in both products. In 2004, 78,213 enrollees in these products received individual outpatient mental health treatment and 1,865 received individual outpatient substance abuse treatment. Methods: To maximize comparability we focus on clinical visits, excluding certain non-clinical services that are unique to EAP programs (e.g. financial counseling). Regression analyses are used to assess the how the number of visits per user per year is affected by the presence/absence of a copayment requirement for initial visits, after controlling for observable characteristics of patients and their employers. We will also use survival analysis to examine whether the integrated product shows a spike in treatment dropout at the point when visits cease to be free. Our hypothesis is that retention will be longer in products where initial visits are free. Results: Descriptive analyses show that, as expected, retention in outpatient substance abuse treatment was longer for the integrated product (where initial visits were free) than for the stand-alone product. In the integrated product 36% of users had more than 3 visits, compared to 29% at the stand-alone product. For outpatient mental health treatment, the pattern is reversed, although the difference is smaller: 55% in the integrated product and 57% in the stand-alone product. Multivariate analyses are under way to verify whether the observed patterns reflect differing case-mix or other differences between the groups. Conclusions: The results of the study will be of interest to employers, insurers, policymakers, and others concerned with improving access to substance abuse and mental health treatment in privately insured populations. If eliminating copayments for initial visits results in better retention in treatment, this could lead to better treatment outcomes and possible savings in other health care spending. Discussant: Vanessa Azzone, Harvard Medical School, USA