Association of Dementia Severity at Diagnosis with Health Care Utilization and Costs around the Time of Incident Diagnosis

Background and Objectives
This study provides the first analysis of heterogeneity in health care use and costs by level of dementia symptom severity around the time of incident dementia diagnosis for a population representative sample of older Americans.

Research Design and Methods
We used the Aging, Demographics, and Memory Study (ADAMS), the Health Retirement Study (HRS), and traditional Medicare (TM) claims. We modeled dementia severity measured by the Clinical Dementia Rating Scale for ADAMS respondents and applied parameter estimates to HRS respondents older than 70 years who had a claims-based incident dementia diagnosis in 2000-2016. We used claims-based measures of health care costs and use and quantified levels in the quarters before, at, and after a dementia diagnosis. We reported separate results for groups of persons diagnosed at mild, moderate, and severe stages of dementia.

Results
Health care use and costs increased a quarter before dementia diagnosis and increased most significantly in the quarter of diagnosis. Both use and costs declined thereafter but remained elevated relative to pre-diagnosis. This general pattern was consistent for persons diagnosed at different stages of dementia. Acute care costs were similar across dementia severity categories throughout the period while outpatient use and costs were consistently higher among persons diagnosed at mild stage disease.

Discussion and Implications
Findings from this study provide new insights on how heterogeneity of dementia severity at diagnosis is associated with health care use and costs. Under the current system of care in TM, early dementia diagnosis may not substantially reduce health care use and spending around the time of dementia diagnosis.