OBJECTIVES: Older adults with Alzheimer’s Disease and Related Dementias (ADRDs) are susceptible to receiving potentially inappropriate medications (PIMs). Dual-eligible beneficiaries can enroll in Medicare Advantage (MA) plans that operate under capitation payments with quality bonus from Medicare, or in the fee-for-service traditional Medicare (TM). Within MA, dual-eligible beneficiaries can choose to enroll in special needs plans (D-SNPs) that are exclusively for dual-eligibles and are required to coordinate Medicare and Medicaid benefits. Our study aims to examine the associations between Medicare enrollment types and PIMs among dual-eligible beneficiaries with ADRD.

METHODS: We used 2016-2019 claims and encounter data from dual-eligible, community-dwelling Medicare beneficiaries > 65 years old with ADRD in the U.S. Measures of PIM were: 1) potentially harmful drug-disease interactions; and 2) high-risk medication use. The explanatory variable is enrollment in D-SNPs, non-D-SNP MA plans, and TM (reference). We estimated linear probability models, controlling for patient age, sex, rurality, health risks captured by other chronic condition burdens and frailty, local health care resources, with county and year fixed effects.

RESULTS: Compared to TM, dual-eligible enrollees with ADRD in D-SNP plans had a similar probability of having potentially harmful drug-disease interactions, but were 1.4-percentage-point more likely to have high-risk medications. Compared to TM, enrollees in non-D-SNP MA plans were 3.0-percentage-point and 2.8-percentage-point less likely to have potentially harmful drug-disease interactions and high-risk medications, respectively. These associations became stronger when patients had higher health risks. The differences between D-SNP plans and other non-D-SNP MA plans were statistically significant.

CONCLUSIONS: While the D-SNP plans are designed to better coordinate care and benefits for dual-eligible beneficiaries, they did not perform better than TM or than other non-D-SNP MA plans to reduce PIMs in those with ADRD. It is important to identify and leverage the features of MA plans that promote safe medication prescribing for dual-eligible beneficiaries with dementia.