Serving persons with severe mental illness in primary care-based medical homes.

OBJECTIVE: Primary care-based medical homes are rapidly disseminating through populations with chronic illnesses. Little is known about how these models affect the patterns of care for persons with severe mental illness who typically receive much of their care from mental health specialists. This study examined whether enrollment in a primary care medical home alters the patterns of care for Medicaid enrollees with severe mental illness.
METHODS: The authors conducted a retrospective secondary data analysis of medication adherence, outpatient and emergency department visits, and screening services used by adult Medicaid enrollees with diagnoses of schizophrenia (N=7,228), bipolar disorder (N=13,406), or major depression (N=45,000) as recorded in North Carolina Medicaid claims from 2004-2007. Participants not enrolled in a medical home (control group) were matched by propensity score to medical home participants on the basis of demographic characteristics and comorbidities. Those dually enrolled in Medicare were excluded.
RESULTS: Results indicate that medical home enrollees had greater use of both primary and specialty mental health care, better medication adherence, and reduced use of the emergency department. Better rates of preventive lipid and cancer screening were found only for persons with major depression.
CONCLUSIONS: Enrollment in a medical home was associated with substantial changes in patterns of care among persons with severe mental illness. These changes were associated with only a modest set of incentives, suggesting that medical homes can have large multiplier effects in primary care of persons with severe mental illness.