Racial and Ethnic Differences in Amyloid PET Positivity in Individuals With Mild Cognitive Impairment or Dementia: A Secondary Analysis of the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) Cohort Study

Consuelo H Wilkins ¹, Charles C Windon ², Peggye Dilworth-Anderson ³

¹Department of Medicine, Division of Geriatric Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.
²Department of Neurology, Memory and Aging Center, Weill Institute for Neurosciences, University of California, San Francisco.
³Health Policy and Management, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill.
⁴Center for Statistical Sciences, Brown University School of Public Health, Providence, Rhode Island.
⁵Department of Epidemiology, Brown University School of Public Health, Providence, Rhode Island.
⁶Center for Research and Innovation, American College of Radiology, Reston, Virginia.
⁷Alzheimer's Association, Chicago, Illinois.
⁸Department of Medicine, Virginia Commonwealth University, Richmond.
⁹Center for Research and Innovation, American College of Radiology, Philadelphia, Pennsylvania.
¹⁰Edward Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Missouri.
¹¹Division of Research, Kaiser Permanente, Oakland, California.
¹²Department of Public Health Sciences, University of California, Davis.
¹³Associate Editor, JAMA Neurology.
¹⁴Department of Radiology & Biomedical Imaging, University of California, San Francisco.

⁰Department of Medicine, Division of Geriatric Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.

Jama Neurology +

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October 3, 2022

View abstract on PubMed

Summary

Racial and ethnic disparities exist in Alzheimer disease (AD) biomarker studies. This analysis of amyloid PET scans in individuals with mild cognitive impairment (MCI) or dementia revealed lower positivity rates in Asian, Black, and Hispanic participants compared to White participants.

Area Of Science

Neuroimaging and Dementia Biomarkers
Racial and Ethnic Health Disparities

Background

Alzheimer disease (AD) clinical presentation and biomarker studies often underrepresent racial and ethnic groups disproportionately affected by the disease.
Amyloid positron emission tomography (PET) is a key biomarker for AD, but its utilization and findings across diverse populations require further investigation.

Purpose Of The Study

To compare amyloid PET positivity rates and odds among diverse racial and ethnic groups within a cohort of individuals diagnosed with mild cognitive impairment (MCI) or dementia.
To investigate potential disparities in amyloid biomarker detection across different racial and ethnic backgrounds in a large-scale study.

Main Methods

Secondary analysis of the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) study, a cohort of Medicare beneficiaries meeting criteria for amyloid PET imaging.
Utilized McNemar test for comparing proportions and multivariable logistic regression to assess odds of amyloid PET positivity between matched racial and ethnic groups.
Analyzed data from 17,107 individuals (Asian, Black, Hispanic, White) with MCI or dementia who underwent amyloid PET scans.

Main Results

White participants showed a higher proportion of positive amyloid PET scans compared to Asian and Hispanic participants.
The odds of having a positive amyloid PET scan were significantly lower for Asian (OR, 0.47), Black (OR, 0.71), and Hispanic (OR, 0.68) participants compared to White participants.
No significant difference in amyloid PET positivity proportion was observed between White and Black participants in the matched analysis.

Conclusions

Significant racial and ethnic differences in amyloid PET positivity were observed in individuals with MCI or dementia.
These disparities may suggest underlying differences in the etiology of cognitive impairment across racial and ethnic groups.
Findings highlight the need for inclusive research and may inform future personalized treatment and prevention strategies for cognitive decline.