Racial disparities in neuropsychological test performance are well documented in Alzheimer's Disease (AD) but have received little attention in frontotemporal degeneration (FTD). Identification of potential disparities in neuropsychological performance is critical to identify ways to improve inclusivity in clinical research and care of representative FTD populations. We evaluated disparities in neuropsychological performance among individuals with clinically diagnosed FTD (behavioral variant FTD [bvFTD] or primary progressive aphasia [PPA]) using data from the National Alzheimer's Coordinating Center (NACC) collected between September 2005 and November 2023. Only 10% of NACC FTD cases are from racially/ethnically minoritized groups. Black (n=56), Hispanic (n=77) and White (n=1301) individuals were evaluated in the cognitive domains of episodic memory, working memory, processing speed, cognitive flexibility, attention, category fluency and lexical retrieval, in addition to global cognition across Uniform Data Set versions 1 to 3. Linear regressions examined the association between racial/ethnic group and cognitive scores covarying for disease stage, age, sex, and education. After adjusting for age, sex, and education using NACC established normative correction, binary logistic regression examined group differences in the proportion of participants classified as impaired (<=-1.5 normative z-score) for each cognitive test. Minoritized individuals, on average, had lower scores and/or greater likelihood of impairment (odds ratio; OR) on measures of global cognition (Black: β = -3.63; OR = 2.74; Hispanic: β = -2.50), lexical retrieval (Black: β = -4.31; OR = 3.28; Hispanic: β = -2.90; OR = 3.81), processing speed (Black: β = 26.80; OR = 4.07; Hispanic: β = 21.31; OR = 2.37), cognitive flexibility (Black: β = 46.65; OR = 3.35), attention (Hispanic: β = -0.39), working memory (Black: β = -0.79; Hispanic: β = -0.42), episodic memory (Hispanic: β = -1.67), and category fluency (Hispanic: β = -1.28). We did not identify any neuropsychological tests where White individuals performed worse than minoritized individuals. These findings indicate racial/ethnic differences in neuropsychological test performance on measures of global cognition, executive function, and lexical retrieval. Critically, these tests are used in diagnosis and monitoring of FTD. Future efforts must focus on increasing research participation in underrepresented populations with FTD to support the diverse needs of individuals, and an understanding of social determinants of health in FTD to evaluate potential sources of the observed differences across racial and ethnic groups.
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