Emergency Department Use Before Dementia Diagnosis in Rural and Urban Medicare Beneficiaries

Early recognition of Alzheimer's disease and related dementias (ADRD) can open the door to timely care and support. This study examines the emergency department (ED) role in first ADRD diagnosis among rural and urban Medicare beneficiaries.

ADRD is often underdiagnosed or diagnosed late, so Medicare claims reflect both underlying dementia and whether it was recognized and documented. A 2026 validation study found that claims-based criteria in the Dementia DataHub identified about half of the people classified with dementia in the Health and Retirement Study, with performance varying by urban–rural status and census division. Rural fee-for-service (FFS) Medicare beneficiaries also had lower rates of diagnosed dementia and patterns consistent with later diagnosis than urban beneficiaries.

ED visits often rise just before a new dementia diagnosis, and 17 percent of FFS beneficiaries with a new diagnosis are first diagnosed during a hospital stay, more often in rural than urban areas. Whether the ED plays a different role in diagnosis for rural beneficiaries is unknown. This study will address that gap among both FFS and Medicare Advantage beneficiaries.

Because rural residents may have fewer local specialty and outpatient options, an ED visit can be a key opportunity to recognize cognitive impairment and connect patients and families to follow-up care. This can support early recognition and screening, referrals, care coordination, and caregiver support.

The study will use Medicare FFS inpatient and outpatient claims, Medicare Advantage inpatient and outpatient encounter data, and Medicare Master Beneficiary Summary File data for enrollment, demographics, and residence. It will address two research questions:

1. Does ED use change in the months before a first documented ADRD diagnosis, and does this pattern differ by rurality and age? This question examines whether ED use rises as beneficiaries approach diagnosis, and whether the size or timing of the increase differs between rural and urban beneficiaries.
2. What proportion of rural and urban beneficiaries with ADRD receive their initial diagnosis with an associated ED encounter, including treat-and-release visits and hospitalizations that begin in the ED, compared with diagnoses first made in other settings?