Effects of Medicare Part D and the Health Implications of Medication Therapy Management Eligibility Criteria

Objectives: Determine whether the implementation of the Medicare Part D 2006 was associated with changes in differential racial and ethnic disparity patterns between the individuals ineligible for medication therapy management (MTM) services and MTM-eligible individuals. The urgency for modifying MTM eligibility criteria would be increased if the reduction of disparity not seen.

Methods: Data from the Medicare Current Beneficiary Survey were analyzed. A difference-in-differences analyses, difference-in-differences-in-differences-in-differences (DDDD) model, was used to examine changes in difference in disparities between the MTM-ineligible and MTM-eligible individuals from 2004-2005 to 2007-2008 in relation to the changes from 2001-2002 to 2004-2005. Disparities were examined in health outcomes, health services utilizations/costs, and medication utilization. Both main and sensitivity analyses were conducted by various regression models.

Findings: The main analysis found no significant DDDD values. For racial disparities, according to some sensitivity analyses, Part D implementation was associated with a reduction in greater racial disparities among the MTM-ineligible and MTM-eligible individuals in activities of daily living (DDDD=1.13; P=0.03 for one analysis) and instrumental activities of daily living (DDDD=0.95; P=0.03 for one analysis). For ethnic disparities, Part D implementation was associated with reduction in any greater disparities among the MTM-ineligible than MTM-eligible individuals in costs of physician visits (DDDD=-4613.71; P=0.04 for one analysis) and high risk medication utilization (DDDD=-0.10; P=0.03 for one analysis).

Conclusions: Part D implementation is not consistently associated with reductions in the disparity implications of the Medicare MTM eligibility criteria. The MTM eligibility criteria need to be modified in order to eliminate their disparity implications.