(HealthDay News) — Racial and ethnic minority groups are underrepresented in Alzheimer disease neuroimaging literature, according to a study published online July 25 in Communications Medicine.

Aaron C. Lim, PhD, from the Keck School of Medicine of USC in Alhambra, California, and colleagues identified median race/ethnicity composition of Alzheimer’s disease neuroimaging US-based research samples in published studies. Studies that directly reported race/ethnicity data (direct studies) and those that did not report race/ethnicity, but used data from a cohort study/database that did report this information (indirect studies), were analyzed.

The researchers found that in the 719 direct studies, the median representation was 88.9% white or 87.4% non-Hispanic white, 7.3 percent Black/African American and 3.4% Hispanic/Latino ethnicity; no Asian American, Native Hawaiian/Pacific Islander, and American Indian/Alaska Native, multiracial, or “other race” participants were included. The 44 cohort studies/databases from which 1,745 indirect studies were derived were more diverse and included median representation of 84.2% white, 83.7% non-Hispanic white, 11.6% Black/African Americans, 4.7% Hispanic/Latino, and 1.75% Asian American participants. Most of the indirect studies (94%) were derived from 10 cohort studies/databases. Sample diversity improved recently comparing two time periods using a median split for publication year (1994 to 2017 and 2018 to 2022), especially for Black/African American participants (3.39 and 8.29% in 1994-2017 and 2018-2022, respectively).

“This is a pretty big deal, especially as we look toward the future, where an increasing proportion of the US will be ethnic minority groups,” Lim said in a statement.

Abstract/Full Text