: Disabled, low income Americans who receive both Medicaid and Medicare insurance coverage (i.e., dual enrollees), represent one of the fastest growing segments of the Medicare population. About one-third of these beneficiaries (est. 2.5 million) have expensive, often debilitating mental illness, including schizophrenia and bipolar disorder. Poor drug treatment adherence among these dual enrollees leads to worse health and expensive downstream clinical events including hospitalizations for severe mental illness (SMI). The Medicare Modernization Act of 2003 (MMA) transferred the responsibility for outpatient prescription drug coverage for dual enrollees from individual state Medicaid programs to private Part D plans funded by the Medicare program on January 1, 2006. The Centers for Medicare and Medicaid Services (CMS) randomly assigns dual beneficiaries to Part D Prescription Drug Plans (PDPs) with relatively low premiums. These standalone PDPs can vary in the numbers and types of prescription drugs included in the plan formulary and can employ utilization management approaches such as prior authorization (PA) for any drug prescriptions. Because each state determined its own Medicaid coverage policies, dual beneficiaries faced a range of drug coverage benefits prior to their transition to Part D coverage. For example, in 15 states, dual enrollees had caps on the number of prescriptions. Thus, the transition to Part D in 2006 expanded their drug coverage and removed a potential risk factor for costly adverse health events. Most states, however, excluded antipsychotic and anticonvulsant therapy from Medicaid prior authorization (PA), while PDPs often use PA as the primary approach for managing drug costs. Thus, as drug coverage responsibility shifts from states to private plans, dually enrolled beneficiaries face fewer state-determined cost barriers to outpatient prescription drug access, but potentially more plan-determined administrative barriers to psychotropic drug access. We will analyze the impact of Part D separately in four large and geographically diverse states: two that placed caps on the number of prescriptions and had relatively higher copayments between 2004 and 2007 (South Carolina: limit of 4 prescriptions per month;California: limit of 6 per month), and two that had no caps and relatively lower copayments during the same period (Missouri, New Jersey).
In Aim 1, we will use a strong quasi-experimental design, Multiple Interrupted Time Series, to examine the population level impacts of this transition on: (1) the prevalence and persistence of psychiatric medication use;(2) use of non-drug psychiatric services;and (3) costs.
In Aim 2 we use a randomized design at the patient level to estimate the effect of coverage restrictions on use of psychiatric medications (including discontinuation and switching of medications), psychiatric outpatient and ER visits, and costs.
In Aim 3 we will use both designs to examine the impact of the policy changes among at-risk subgroups (defined by somatic comorbidities and minority status) of patients with schizophrenia and bipolar disorder.

Public Health Relevance

This study will evaluate the impacts of changes in drug cost containment policies that occurred with the shift from Medicaid coverage to Medicare Part D drug coverage on access to psychiatric medications and quality of care for disabled people with schizophrenia or bipolar disorder in four states. The study findings have relevance not only for those who transitioned to Medicare Part D in 2006, but for the continuing stream of disabled Medicaid beneficiaries who qualify for disability status and transition to Medicare Part D medication benefits after a two year waiting period.

National Institute of Health (NIH)
Agency for Healthcare Research and Quality (AHRQ)
Research Project (R01)
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Health Systems Research (HSR)
Program Officer
Hagan, Michael
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Harvard Pilgrim Health Care, Inc.
United States
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Adams, Alyce S; Madden, Jeanne M; Zhang, Fang et al. (2017) Effects of Transitioning to Medicare Part D on Access to Drugs for Medical Conditions among Dual Enrollees with Cancer. Value Health 20:1345-1354
Burns, Marguerite E; Huskamp, Haiden A; Smith, Jessica C et al. (2016) The Effects of the Transition From Medicaid to Medicare on Health Care Use for Adults With Mental Illness. Med Care 54:868-77
Briesacher, Becky A; Madden, Jeanne M; Zhang, Fang et al. (2015) Did Medicare Part D Affect National Trends in Health Outcomes or Hospitalizations? A Time-Series Analysis. Ann Intern Med 162:825-33
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Madden, Jeanne M; Adams, Alyce S; LeCates, Robert F et al. (2015) Changes in drug coverage generosity and untreated serious mental illness: transitioning from Medicaid to Medicare Part D. JAMA Psychiatry 72:179-88
Burns, Marguerite E; Busch, Alisa B; Madden, Jeanne M et al. (2014) Effects of Medicare Part D on guideline-concordant pharmacotherapy for bipolar I disorder among dual beneficiaries. Psychiatr Serv 65:323-9
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Adams, Alyce S; Madden, Jeanne M; Zhang, Fang et al. (2014) Changes in use of lipid-lowering medications among black and white dual enrollees with diabetes transitioning from Medicaid to Medicare Part D drug coverage. Med Care 52:695-703