Part D Plan Switching Among Medicare Beneficiaries With Schizophrenia

Objective: Most Medicare schizophrenia patients were randomly assigned in 2006 to one of 409 benchmark plans. This study examined plan switching and factors affecting switching among beneficiaries with schizophrenia. Methods: The data were 2006 Medicare pharmacy data for three groups of schizophrenia patients: those with Medicaid coverage ("dual eligibles"; N=93,705), Medicare beneficiaries with a low-income subsidy (N=56,148), and Medicare beneficiaries without the subsidy (N=36,107). Switching frequency and how patient and plan characteristics affected switching were examined. Results: Beneficiaries who switched their Part D plan at least once included 10.7% of the dual eligibles, 9.8% of those with a subsidy, and 5.5% of those without. Several factors affected likelihood of switching, including age, geographic region, and proportion of prescriptions filled by beneficiaries who were covered or whose prescriptions required utilization review in the original plan. Conclusions: Plan switching among Medicare beneficiaries with schizophrenia was relatively infrequent but may be driven by the need for better drug coverage and less restrictive utilization policies.