Trends in observation stays for Medicare beneficiaries with and without Alzheimer's disease and related dementias

Background There has been a marked rise in the use of observation care for Medicare beneficiaries visiting the emergency department (ED) in recent years. Whether trends in observation use differ for people with Alzheimer's disease and Alzheimer's disease‐related dementias (AD/ADRD) is unknown. Methods Using a national 20% sample of Medicare beneficiaries ages 68+ from 2012 to 2018, we compared trends in ED visits and observation stays by AD/ADRD status for beneficiaries visiting the ED. We then examined the degree to which trends differed by nursing home (NH) residency status, assigning beneficiaries to four groups: AD/ADRD residing in NH (AD/ADRD+ NH+), AD/ADRD not residing in NH (AD/ADRD+ NH‐), no AD/ADRD residing in NH (AD/ADRD‐ NH+), and no AD/ADRD not residing in NH (AD/ADRD‐ NH‐). Results Of 7,489,780 unique beneficiaries, 18.6% had an AD/ADRD diagnosis. Beneficiaries with AD/ADRD had more than double the number of ED visits per 1000 in all years compared to those without AD/ADRD and saw a faster adjusted increase over time (+26.7 vs. +8.2 visits/year; p