Medicare Part D Coverage Gap and Restrictions: Race, Gender, and Cost-Related Medication Nonadherence

Background and Purpose:  There is concern that the Medicare Part D cost-containment provisions can inhibit the use of medications, particularly for older women and Black Americans. Compared to older men and Whites, older females and Black Americans are more reliant on pharmaceuticals. Because their overall medication costs and utilization are higher, they have a greater likelihood of incurring the Medicare Part D coverage gap and restrictions. To date, studies have not examined whether racial and gender disparities in cost-related medication nonadherence (CRN) exist under Medicare Part D plans or how the coverage gap and restrictions affect differences in nonadherence. The objectives of this study were to determine: 1) to what extent race and gender impact the likelihood of CRN under Medicare Part D plans; and 2) to what extent the Medicare Part D coverage gap and restrictions directly and indirectly affect the relationship between race, gender, socioeconomic and health status and CRN.

Methods: To evaluate CRN, secondary data from the 2006 wave of the Health and Retirement Study (HRS) and data from the 2007 wave of the Prescription Drug Study (PDS) were utilized. The sample for this cross-sectional analysis consisted of 1,353 respondents age 65 and older who were enrolled in Medicare Part D, taking at least one prescribed medication, and who responded to questions about adherence or nonadherence in 2007. The outcome variable of interest was CRN, which included not filling, stopping, or skipping doses of a prescription because of cost. The main predictors were race (Black American and White), gender (male and female), Medicare Part D coverage gap (reached gap, did not reach gap, and no coverage gap), and coverage restrictions (experienced restrictions and did not experience restrictions). Covariates included demographics, socioeconomic, and health status. The analysis was conducted using logistic regression models.

Results: Results indicated that racial disparities in CRN existed under Medicare Part D after accounting for demographics, health status, socioeconomic status, and the coverage restrictions. However, the inclusion of the coverage gap variable mediated differences in CRN between older Black Americans and Whites. Having a coverage gap or coverage restrictions had a direct effect on CRN. Poorer health status, lower income, and having applied for the Low-Income Subsidy (LIS) increased the likelihood of nonadherence, even after accounting for the coverage gap and restrictions.

Conclusions and Implications:  While gender disparities did not exist, racial differences in CRN were substantially driven by the Medicare Part D coverage gap. Further, socioeconomic and health status continue to impact CRN. Despite the establishment of a drug benefit under Medicare, social workers should be aware that CRN can still be problematic, and racial differences in the CRN continue to exist. Understanding how Medicare Part D has affected adherence can help social work practitioners recognize that clients may need additional resources and assistance in order to avoid CRN, particularly when reaching the coverage gap or incurring coverage restrictions. Additionally, findings can help substantiate the need to account for race when evaluating policy alternatives in order to promote more equitable access to medications.