Cerebral Amyloid Angiopathy: Similarity in African-Americans and Caucasians with Alzheimer’s Disease

Article type: Research Article

Authors: Kamara, Dennis M.^{a; 1} | Gangishetti, Umesh^{b; 1} | Gearing, Marla^c | Willis-Parker, Monica^b | Zhao, Liping^d | Hu, William T.^b | Walker, Lary C.^{b; e; *}

Affiliations: [a] Department of Biology, Emory University, Atlanta, GA, USA | [b] Department of Neurology and Alzheimer’s Disease Research Center, Emory University, Atlanta, GA, USA | [c] Department of Pathology and Alzheimer’s Disease Research Center, Emory University, Atlanta, GA, USA | [d] Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA | [e] Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA

Correspondence: [*] Correspondence to: Lary C. Walker, Department of Neurology, Emory University, 505M Whitehead Building, 615 Michael Street, Atlanta, GA 30322, USA. E-mail: lary.walker@emory.edu.

Note: [1] These authors contributed equally to this work.

Abstract: Cerebral amyloid angiopathy (CAA) of the Aβ type is variably present in the brains of patients with Alzheimer’s disease (AD). CAA contributes to cognitive decline and increases the risk of lobar hemorrhage; because both AD-typical dementia and lobar hemorrhage are more common in African-Americans than in Caucasians, we postulated that African-Americans with AD might be particularly susceptible to CAA. To test this hypothesis, we analyzed CAA histopathologically in the large vessels and capillaries of autopsy-derived frontal, temporal, parietal, and occipital cortical samples from African-Americans (n = 18) and Caucasians (n = 19) with end-stage AD. In the combined cohort of 37 subjects, 22% of the subjects had severe CAA in large vessels, and 11% had severe CAA in capillaries. However, the prevalence and histopathologic characteristics of CAA were similar in the African-Americans and Caucasians. This conclusion was substantiated in an independent sample from the National Alzheimer’s Coordinating Center database, in which the degree of CAA was comparable in 1,554 Caucasians and 68 African-Americans with end-stage AD. These findings support a growing consensus that the fundamental histopathologic features of AD are largely impartial to the race of the afflicted.

Keywords: Aβ, aging, amyloid, cerebrovascular amyloidosis, dementia, ethnicity, race, tauopathy, vascular disease

DOI: 10.3233/JAD-170954

Journal: Journal of Alzheimer's Disease, vol. 62, no. 4, pp. 1815-1826, 2018