Dementia severity at incident diagnosis in a population representative sample of older Americans.

Abstract

We provide the first analysis of distribution of dementia severity at incident diagnosis for a population representative sample of older Americans. Using data from the Aging, Demographics, and Memory Study (ADAMS), the Health Retirement Study (HRS), and traditional Medicare claims, we estimated the Clinical Dementia Rating Scale for ADAMS respondents and applied parameter estimates to predict dementia severity for HRS respondents with claims-based incident dementia diagnosis. Seventy percent of older adults received a dementia diagnosis of mild cognitive impairment or mild dementia (early stages). Fewer individuals were diagnosed at early stages in years 2000 to 2008 (65%) compared to years 2009 to 2016 (76%). About 72% of non-Hispanic white persons were diagnosed at early stages, compared to 63% non-Hispanic black and 59% Hispanic persons. More males than females were diagnosed at early stages (75%vs 67%). These data linkages allow population surveillance of early and equitable dementia detection in the older US population to assess clinical and policy levers to improve detection. For the US population 70 and older, 30% were diagnosed with dementia at a moderate or severe stage.Fewer were diagnosed at early stages in years 2000 to 2008 compared to 2009 to 2016 (65%vs 76%).A total of 72% of white persons were diagnosed at early stages, compared to 63% black and 59% Hispanic persons.More males than females were diagnosed at early stages (75%vs 67%).High wealth and education level were associated with diagnosis at early stages disease.