The epidemiology of mild cognitive impairment, Alzheimer's disease and related dementia in U.S. veterans

Introduction: US veterans have a unique dementia risk profile that may be evolving over time. Methods: Age-standardized incidence and prevalence of Alzheimer's disease (AD), AD and related dementias (ADRD), and mild cognitive impairment (MCI) was estimated from electronic health records (EHR) data for all veterans aged 50 years and older receiving Veterans Health Administration (VHA) care from 2000 to 2019. Results: The annual prevalence and incidence of AD declined, as did ADRD incidence. ADRD prevalence increased from 1.07% in 2000 to 1.50% in 2019, primarily due to an increase in the prevalence of dementia not otherwise specified. The prevalence and incidence of MCI increased sharply, especially after 2010. The prevalence and incidence of AD, ADRD, and MCI were highest in the oldest veterans, in female veterans, and in African American and Hispanic veterans. Discussion: We observed 20-year trends of declining prevalence and incidence of AD, increasing prevalence of ADRD, and sharply increasing prevalence and incidence of MCI.