Abstract:
Background: Previous studies have shown that there were greater racial and ethnic disparities among individuals who were ineligible for medication therapy management (MTM) services than among MTM-eligible individuals before the implementation of Medicare Part D in 2006.
Objective: To determine whether the implementation of Medicare Part D in 2006 correlates to changes in racial and ethnic disparities among MTM-ineligible and MTM-eligible beneficiaries.
Methods: Data from the Medicare Current Beneficiary Survey were analyzed in this retrospective observational analysis. To examine potential racial and ethnic disparities, non-Hispanic whites were compared with non-Hispanic blacks and Hispanics. Three aspects of disparities were analyzed, including health status, health services utilization and costs, and medication utilization patterns. A generalized difference-in-differences analysis was used to examine the changes in difference in disparities between MTM-ineligible and MTM-eligible individuals from 2004-2005 to 2007-2008 relative to changes from 2001-2002 and 2004-2005. Various multivariate regressions were used based on the types of dependent variables. A main analysis and several sensitivity analyses were conducted to represent the ranges of MTM eligibility thresholds used by Medicare Part D plans in 2010.
Results: The main analysis showed that Part D implementation was not associated with reductions in greater racial and ethnic disparities among MTM-ineligible than MTM-eligible Medicare beneficiaries. The main analysis suggests that after Part D implementation, Medicare MTM eligibility criteria may not consistently improve the existing racial and ethnic disparities in health status, health services utilization and costs, and medication utilization. By contrast, several sensitivity analyses showed that Part D implementation did correlate with a significant reduction in greater racial disparities among the MTM-ineligible group than the MTM-eligible group in activities of daily living and in instrumental activities of daily living. Part D implementation may be also associated with a reduction in greater ethnic disparities among the MTM-ineligible group than the MTM-eligible groups in the costs of physician visits.
Conclusion: Part D implementation was not associated with consistent reductions in the disparity implications of the Medicare MTM eligibility criteria. The main analysis showed that Part D implementation was not associated with a reduction in disparities associated with MTM eligibility, although several sensitivity analyses did show reductions in disparities in specific aspects. Future research should explore alternative Medicare MTM eligibility criteria to eliminate racial and ethnic disparities among the Medicare population.