Medicaid Enrollment Patterns Among People with Serious Mental Illnesses

Background: Medicaid is the largest payee of mental health services in the United States. It provides health insurance for nearly 30 million low-income adults and is the primary source of insurance for people with serious mental illnesses (SMI). Research has found that even relatively small breaks in Medicaid coverage have adverse effects on service use and health outcomes.  However, little research has focused on Medicaid disruptions among people with SMI because their connection to treatment services is thought to facilitate coverage continuity. This paper presents research that tests this assumption by examining the rates of Medicaid disruptions among people with SMI, and examines the extent to which mental health diagnoses predict Medicaid enrollment stability.

Methods:  A retrospective longitudinal cohort study examined the Medicaid enrollment patterns between 2007-2010 for a cohort of people with SMI who received treatment services through the public mental health system in 2006. This cohort included 9,676 adults with SMI, age 18-61, living in a large metropolitan area in the Midwest. The mean age of participants was 40.3 (SD = 11.3). Six-three percent of participants were women, 48% were black, and 69% were single. Thirty-nine percent of participants had a primary diagnosis of schizophrenia, 33% major depression, 19% bipolar disorder, and 10% anxiety disorder. Descriptive statistics and logistic regression models were used to examine Medicaid enrollment patterns among people with SMI, as well as the relationship between mental health diagnosis and Medicaid enrollment continuity.

Results: The results of this study found that only 38% of participants were continuously enrolled in Medicaid during the study period. Of the remaining 62% of participants, 43% experienced one disruption and 19% experienced two or more disruptions (i.e. churn) in Medicaid enrollment. Multivariate analyses found that mental health diagnosis was not predictive of continuous Medicaid enrollment, however, individuals with schizophrenia were 29% more likely to churn than those with depression (B = 0.26; p<.001) and 41% more likely to churn than individuals with anxiety (B = 0.34; p<.01).  Individuals with bipolar disorder did not have significantly different odds of churning than individuals with schizophrenia.

Conclusions and Implications:  This is one of the first studies to look at Medicaid enrollment patterns among a cohort of people with different mental health diagnoses. These results challenge the notion that the presence of a serious mental illness mitigates Medicaid discontinuity. These findings point to the need for more research on the enrollment patterns of this population since Medicaid is a primary insurer of treatment services for people with SMI.  Future research needs to explore the mechanisms behind Medicaid instability among people with SMI and what interventions are needed to support stable Medicaid enrollment and adequate access to mental health services among this population.