Dementia Prevalence in Older Adults: Variation by Race/Ethnicity and Immigrant Status

To examine differences in prevalence and risk factors of dementia by race/ethnicity and immigrant status using a nationally representative sample of Medicare beneficiaries.

This was a cross-sectional study performed in the United States among non-Hispanic white (NHW), non-Hispanic black (NHB), Hispanic, and other Medicare beneficiaries from round 1 of the National Health and Aging Trends Study (N = 7,609). The authors used log-binomial regression analyses to investigate risk factors and interactions between race/ethnicity and immigrant status and dementia. Stratified log-binomial regression analyses by race/ethnicity were used to interpret the results of interaction effects of immigrant status found in these surveys. Analyses were conducted in three forms: probable dementia versus possible and no dementia, probable and possible dementia versus no dementia; and probable dementia versus no dementia.

Consistent with previous studies, U.S.-born NHBs have a higher prevalence of dementia than U.S.-born whites, Hispanics, and others. Immigrant status moderated the relationship between race/ethnicity and dementia. NHWs, Hispanics, and other immigrants had a higher prevalence of dementia compared with their U.S.-born counterparts. However, U.S.-born NHBs had a higher prevalence of dementia compared with NHB immigrants. Results were consistent across the three forms of analysis. Greater age predicted higher dementia across the four racial/ethnic groups.

Immigrant status may have complex effects on dementia risk. Selection factors affecting immigration-varied health and educational systems in diverse countries of origin, acculturative stress, and validity of dementia assessment across diverse groups-deserve further attention.