Little progress in reducing relative racial disparities in the incidence and prevalence of dementia in the United States, 2000‐2016

Background In the United States (U.S), risk of dementia is higher in non‐Hispanic black or African American populations than in non‐Hispanic white populations. Recent reports suggest declining or stable dementia prevalence and incidence, which may impact the degree of racial disparities. Our objective was to examine whether racial disparities in dementia prevalence or incidence have changed in the U.S. from 2000 to 2016. Method We leverage data from non‐Hispanic white and non‐Hispanic black participants ages 70 and older from the 2000 to 2016 waves of the U.S. nationally‐representative Health and Retirement Study (HRS). For analyses of secular trends in racial disparities in dementia prevalence, we consider each HRS wave separately. For analyses of secular trends in racial disparities in dementia incidence, we created seven sub‐cohorts, which followed all eligible persons without dementia classification at baseline for seven distinct four‐year intervals: 2000‐2004, 2002‐2006, 2004‐20108, 2006‐2010, 2008‐2012, 2010‐2014, and 2012‐2016. Participant race/ethnicity was based on participant response to closed‐ended survey questions. We determined dementia status for all HRS participants at each wave using three previously developed and validated algorithms designed for use in HRS‐based studies of racial/ethnic disparities in dementia. These algorithms assign dementia status based on information gathered at HRS study visits, and were designed to have similar out‐of‐sample sensitivity and specificity across non‐Hispanic white and non‐Hispanic black subgroups. We characterized disparities using ratio measures. Result While overall dementia prevalence declined from 2000 to 2016 in age‐ and sex standardized analyses, overall dementia incidence remained stable from 2000 to 2016. There was no evidence of secular trends in the magnitude of relative racial disparities in dementia prevalence or incidence. The prevalence of dementia in older non‐Hispanic black Americans remained approximately twice the prevalence in non‐Hispanic white Americans, and the incidence of dementia in non‐Hispanic black Americans was approximately 50‐60% greater than that observed in non‐Hispanic white Americans from 2000 to 2016 Conclusion There is no evidence to suggest U.S. racial/ethnic disparities in dementia risk changed between 2000 and 2016. Additional efforts to identify and mitigate the source of these disparities is warranted.