Dual-eligibles with a psychiatric illness are a particularly vulnerable subgroup of Medicare beneficiaries, and some patient advocates and policymakers were concerned that the shift from Medicaid drug coverage to enrollment in a private Part D plan would result in difficulties accessing medications and possibly negative mental health outcomes for this group. The special protections for medication classes used commonly by individuals with mental disorders were intended to address this concern by guaranteeing formulary coverage of these medications. However, many plans use management tools such as prior authorization and step therapy to control utilization of psychopharmacologic medications. While use of these tools may lead to a more efficient allocation of resources and could possibly result in higher quality of care in some cases, utilization management requirements could also create access issues for enrollees. For example, Soumerai and colleagues’ study of the atypical antipsychotic prior authorization and step therapy policies implemented in Maine’s Medicaid program indicated these policies were associated with a 29% greater risk of antipsychotic discontinuations compared to a comparison state, with no associated cost savings in drug expenditures.(13
) The requirement that all dual-eligibles pay copays to receive medications may also create access issues for some duals.
In fact, we found that almost half of the dual-eligible patients in our sample experienced some form of medication access problem in 2006. Although one might expect rates of access problems to decline over the course of the year, West et al. (2009) found no decline -- in fact, the rate of access problems reported by psychiatrists actually increased slightly as the year progressed, perhaps due in part to the transition policy.(14
) Rates of difficulties accessing medications might also be expected to decrease after the first year of implementation, although a large number of dual-eligibles either switch plans or are reassigned to a different benchmark plan each year. For example, between 2006 and 2007, 1.1 million dual-eligibles were reassigned to another plan when their plan’s premium bid exceeded the new benchmark for the coming year; between 2007 and 2008, 2.1 million were reassigned.(3
) Thus, during a given year a large proportion of dual-eligibles will likely face different coverage and utilization management requirements under a new plan and thus may be at particular risk for access problems. Access problems may also occur for beneficiaries who remain in the same plan if that plan changes formulary coverage and management procedures over time as permitted.
Although disruptions in medication continuity among psychiatric patients have been shown to be associated with high rates of symptom relapse or exacerbation, hospitalization, and other adverse consequences (15
), some of the access issues we observed may have been resolved expeditiously, with little harm to the patient. For example, if a claim was initially rejected because prior authorization was required and authorization was granted quickly, the enrollee may have been able to fill the original prescription before a negative health outcome occurred. The timeliness of authorizations has been shown to be critically important for patients with schizophrenia.(20
) Consequently, patients who experienced significant disruptions or gaps in medication continuity may have been more likely to relapse and present in the emergency room. Other patients may have switched medications in response to Part D coverage rules, and the effectiveness and/or tolerability of the “new” medication could have been either better or worse for the patient than their “old” drug. Findings from the CATIE study indicate that individuals randomly assigned to olanzapine or risperidone who were continuing with the medication they were taking at baseline had a longer time to discontinuation relative to individuals assigned to switch antipsychotics.(21
) The consequences of switching medications may vary, however, based on the nature of the switch (e.g., a therapeutic substitution from one molecule to another versus a generic substitution). We estimated that patients who experienced an access problem were significantly more likely to have an emergency room visit for the treatment of a psychiatric illness, but were not more likely to have a psychiatric hospitalization.
Our findings should be interpreted in the context of several limitations. First, we measure a patient’s experience of a medication access problem and the patient’s use of psychiatric emergency room and hospital care in the first twelve months after Part D’s implementation using reports from their psychiatrist. The psychiatrists may not be aware of all access problems experienced by the patient and all services used, or recall bias could be an issue if the psychiatrist did not provide sufficient documentation in the patient’s medical record regarding these issues. We did not have data on the timing of access problems, emergency room use, and hospitalizations within the twelve-month period, which limits our ability to fully examine the relationship between medication access problems and use of these intensive services. Also, the high proportion of patients who experienced medication access problems during the first twelve months of 2006 likely reflects in part the widespread confusion when Part D was first implemented. The relatively high rate of reported access problems motivated us to use propensity score matching to allow us to compare individuals who were similar with respect to observable demographic and clinical characteristics. Second, our propensity score models are only able to reduce differences between the intervention and comparison groups in observed confounders; we are unable to control for differences in unobserved confounders. Third, we do not have information on additional office visits that may have resulted from medication access problems (e.g., a follow-up visit to check on a patient who had to switch medications because of lack of coverage). Finally, the dual-eligible patients we studied were all in the care of a psychiatrist, so our findings may not be generalizable to all dual-eligibles with a psychiatric disorder. However, psychiatrists treat the majority of individuals receiving treatment for schizophrenia and many individuals with other severe mental illnesses, and a disproportionate share of dual-eligibles suffer from one of these conditions. (22