Lower tau levels may obscure early Alzheimer’s in black patients

  • Two large studies show an association between the Alzheimer's protein tau and the Alzheimer's gene APOE4, but the association varies across race and gender.

Data from 1,215 older adults, of whom 173 (14%) were African-American, has found that, although brain scans showed no significant differences between black and white participants, cerebrospinal fluid (CSF) showed significantly lower levels of the brain protein tau in African-Americans.

While both groups showed the same (expected) pattern of higher tau levels being associated with greater chance of cognitive impairment, the absolute amounts of tau protein were consistently lower in African-Americans.

However, when APOE status was taken into account, it was found that those who held the low-risk variants of the “Alzheimer’s gene” had similar levels of tau, regardless of race. It was only African-Americans with the APOE4 gene variant that showed lower levels of tau.

This suggests that the APOE4 risk factor has different effects in African-Americans compared to non-Hispanic white Americans, and points to the need for more investigation into how Alzheimer’s develops in various populations.

Interestingly, another study, using data from 1798 patients (of whom 1690 were white), found that there was a strong gender difference in the association between APOE status and tau levels in the CSF.

Previous research has shown that the link between APOE4 and Alzheimer's is stronger in women than men. This study points to a connection with tau levels, as there was no gender difference in the association between APOE and amyloid-beta levels, amyloid plaques, or tau tangles.

https://www.futurity.org/alzheimers-disease-black-patients-1951502/

Reference: 

Morris JC, Schindler SE, McCue LM, et al. Assessment of Racial Disparities in Biomarkers for Alzheimer Disease. JAMA Neurol. Published online January 07, 2019. doi:10.1001/jamaneurol.2018.4249

Hohman TJ, Dumitrescu L, Barnes LL, et al. Sex-Specific Association of Apolipoprotein E With Cerebrospinal Fluid Levels of Tau. JAMA Neurol. 2018;75(8):989–998. doi:10.1001/jamaneurol.2018.0821

 

Related News

Analysis of data from 237 patients with mild cognitive impairment (mean age 79.9) has found that, compared to those carrying the ‘normal’ ApoE3 gene (the most common variant of the ApoE gene), the ApoE4 carriers showed markedly greater rates of shrinkage in 13 of 15 brain regions thought to be k

Analysis of data from more than 8,000 people, most of them older than 60, has revealed that, among the 5,000 people initially tested cognitively normal, carrying one copy of the “Alzheimer’s gene” (ApoE4) only slightly increased men’s risk of developing

Analysis of 700 subjects from the Alzheimer's Disease Neuroimaging Initiative has revealed a genetic mutation (rs4728029) that’s associated with people who develop Alzheimer’s pathology but don’t show clinical symptoms in their lifetime.

Analysis of brain scans and cognitive scores of 64 older adults from the NIA's Baltimore Longitudinal Study of Aging (average age 76) has found that, between the most cognitively stable and the most declining (over a 12-year period), there was no significant difference in the total amount of amy

A pilot study involving 94 older adults, of whom 18 had Alzheimer’s, 24 had

Data from 6257 older adults (aged 55-90) evaluated from 2005-2012 has revealed that concerns about memory should be taken seriously, with subjective complaints associated with a doubled risk of developing mild cognitive impairment or dementia, and subjective complaints supported by a loved on

Analysis of mitochondrial DNA (mtDNA) in the cerebrospinal fluid has found that both symptomatic Alzheimer’s patients and asymptomatic patients at risk of Alzheimer

Comparison of the EEGs of 27 healthy older adults, 27 individuals with mild Alzheimer's and 22 individuals with moderate cases of Alzheimer’s, has found statistically significant differences across the three groups, using an algorithm that dissects brain waves of varying frequencies.

Data from two longitudinal studies of older adults (a nationally representative sample of older adults, and the Alzheimer’s Disease Neuroimaging Initiative) has found that a brief cognitive test can distinguish memory decline associated with healthy aging from more serious memory disorders, year

Analysis of 40 spinal marrow samples, 20 of which belonged to Alzheimer’s patients, has identified six

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health newsSubscribe to Latest news