Multiracial participants in Alzheimer's research: scoping review and recommendations

Evidence suggests that Alzheimer's disease (AD) presents differently across ethnoracial groups, producing disparate risk and resilience profiles that may be measured through neuropsychological data. Extant AD research primarily examines monoracial groups, despite the fact that Multiracial individuals make up more than 10% of the US population. Failure to incorporate data from Multiracial participants (those endorsing two or more racial identities) limits research and clinical efforts to address AD in minoritized communities. A scoping review examined the use of neuropsychological data from Multiracial participants within AD research. Three databases were searched (APA PsycInfo, Embase, and Web of Science) for studies containing ethnoracially minoritized groups. Two independent researchers reviewed articles and included studies that met the following criteria: published in 2000 (the year the US Census formally allowed self‐identification of multiple races) or later, in English, US‐based cohort (as race is a social construct), reported neuropsychological data, and the research was AD‐related. Searches yielded 855 original articles. Following abstract review, 484 articles were screened in full, resulting in 19 articles that met the inclusion criteria. Most excluded articles (66.67%) contained vague racial descriptions (e.g., use of an undefined Other Race group), making it difficult to know whether Multiracial participants existed in the dataset. Roughly one‐third (29.03%) of articles were excluded because they described only monoracial groups. Analysis of neuropsychological outcomes showed that most articles included Multiracial participant data in larger group‐level analyses (e.g., normal cognition versus dementia) or grouped their data with other, less represented ethnic or racial groups (e.g., Other Races). This review demonstrates the paucity of research and need for intentional consideration of the inclusion of Multiracial participants in AD research. Recommendations to improve reporting of data from Multiracial participants are offered, including considerations for the anticipation and adaptation to changes in the social definitions of ethnicity and race.