Royse Sarah K, Cohen Ann D, Snitz Beth E, Rosano Caterina
Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States.
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
Front Syst Neurosci. 2021 Jul 21;15:685957. doi: 10.3389/fnsys.2021.685957. eCollection 2021.
The population of older adults with Alzheimer's disease and Related Dementias (ADRD) is growing larger and more diverse. Prevalence of ADRD is higher in African American (AA) and Hispanic populations relative to non-Hispanic whites (nHW), with larger differences for women compared to men of the same race. Given the public health importance of this issue, we sought to determine if AA and Hispanic women exhibit worse ADRD pathology compared to men of the same race and nHW women. We hypothesized that such differences may explain the discrepancy in ADRD prevalence.
We evaluated 932 articles that measured at least one of the following biomarkers of ADRD pathology and/or post-mortem: beta-amyloid (Aß), tau, neurodegeneration, and cerebral small vessel disease (cSVD). Criteria for inclusion were: (1) mean age of participants >65 years; (2) inclusion of nHW participants and either AA or Hispanics or both; (3) direct comparison of ADRD pathology between racial groups.
We included 26 articles (Aß = 9, tau = 6, neurodegeneration = 16, cSVD = 18), with seven including sex-by-race comparisons. Studies differed by sampling source (e.g., clinic or population), multivariable analytical approach (e.g., adjusted for risk factors for AD), and cognitive status of participants. Aß burden did not differ by race or sex. Tau differed by race (AA < nHW), and by sex (women > men). Both severity of neurodegeneration and cSVD differed by race (AA > nHW; Hispanics < nHW) and sex (women < men). Among the studies that tested sex-by-race interactions, results were not significant.
Few studies have examined the burden of ADRD pathology by both race and sex. The higher prevalence of ADRD in women compared to men of the same race may be due to both higher tau load and more vulnerability to cognitive decline in the presence of similar Aß and cSVD burden. AA women may also exhibit more neurodegeneration and cSVD relative to nHW populations. Studies suggest that between-group differences in ADRD pathology are complex, but they are too sparse to completely explain why minority women have the highest ADRD prevalence. Future work should recruit diverse cohorts, compare ADRD biomarkers by both race and sex, and collect relevant risk factor and cognitive data.
患有阿尔茨海默病及相关痴呆症（ADRD）的老年人群数量日益增多且更加多样化。与非西班牙裔白人（nHW）相比，非裔美国人（AA）和西班牙裔人群中ADRD的患病率更高，同种族女性与男性之间的差异更大。鉴于此问题对公共卫生的重要性，我们试图确定非裔美国女性和西班牙裔女性与同种族男性及非西班牙裔白人女性相比，是否表现出更严重的ADRD病理学特征。我们假设这种差异可能解释了ADRD患病率的差异。
我们评估了932篇文章，这些文章测量了以下至少一种ADRD病理学和/或尸检生物标志物：β-淀粉样蛋白（Aß）、tau蛋白、神经退行性变和脑小血管疾病（cSVD）。纳入标准为：（1）参与者的平均年龄>65岁；（2）纳入非西班牙裔白人参与者以及非裔美国人或西班牙裔或两者；（3）种族群体之间ADRD病理学的直接比较。
我们纳入了26篇文章（Aß = 9篇，tau = 6篇，神经退行性变 = 16篇，cSVD = 18篇），其中7篇包括按种族和性别的比较。研究在抽样来源（如诊所或人群）、多变量分析方法（如针对AD风险因素进行调整）以及参与者的认知状态方面存在差异。Aß负担在种族或性别上没有差异。Tau在种族上存在差异（非裔美国人 < 非西班牙裔白人），在性别上也存在差异（女性 > 男性）。神经退行性变和cSVD的严重程度在种族上均存在差异（非裔美国人 > 非西班牙裔白人；西班牙裔 < 非西班牙裔白人），在性别上也存在差异（女性 < 男性）。在测试种族与性别相互作用的研究中，结果不显著。
很少有研究同时按种族和性别来研究ADRD病理学负担。与同种族男性相比，女性中ADRD患病率较高可能是由于tau蛋白负荷较高以及在Aß和cSVD负担相似的情况下更容易出现认知衰退。相对于非西班牙裔白人人群，非裔美国女性可能也表现出更多的神经退行性变和cSVD。研究表明，ADRD病理学的组间差异很复杂，但这些差异过于稀少，无法完全解释为什么少数族裔女性的ADRD患病率最高。未来的研究应招募多样化的队列，按种族和性别比较ADRD生物标志物，并收集相关风险因素和认知数据。
