Department of Psychology, University of Michigan, United States.
Department of Psychology, University of Michigan, United States.
Soc Sci Med. 2023 Jan;316:114789. doi: 10.1016/j.socscimed.2022.114789. Epub 2022 Feb 7.
Non-Hispanic Black older adults are at higher risk of Alzheimer's disease and related dementias (ADRD) than non-Hispanic Whites, which reflects racial disparities in both brain and cognitive health. Discrimination may contribute to these disparities, but much of the research on discrimination and ADRD outcomes is cross-sectional and/or does not disaggregate experiences of discrimination by attribution. Focusing specifically on racial discrimination and considering longitudinal brain outcomes may advance our understanding of the role of discrimination in explaining disproportionate rates of ADRD among non-Hispanic Black older adults.
In total, 221 non-Hispanic Black participants in the Washington Heights-Inwood Columbia Aging Project completed multiple measures of discrimination at one time point and structural magnetic resonance imaging (MRI) scans at two time points. Everyday discrimination and lifetime discrimination were operationalized first as aggregate experiences of discrimination (regardless of identity attributions) and then as racial discrimination per se. MRI outcomes included hippocampal and white matter hyperintensity (WMH) volumes. Latent difference score models estimated associations between the discrimination measures and each MRI outcome over four years.
Aggregate discrimination (regardless of attributions) was not associated with either outcome. Lifetime racial discrimination was associated with lower initial hippocampal volume. Everyday racial discrimination was associated with faster accumulation of WMH over time.
Racial discrimination may be detrimental for brain aging among non-Hispanic Black older adults, which may contribute to their disproportionate dementia burden. Disaggregating discrimination by attribution may clarify research on racial inequalities in brain and cognitive aging, as racial discrimination appears to be particularly toxic.
非裔美国老年人比非裔白人患阿尔茨海默病和相关痴呆症（ADRD）的风险更高，这反映了大脑和认知健康方面的种族差异。歧视可能导致了这些差异，但关于歧视和 ADRD 结果的大部分研究都是横断面的，或者没有根据归因来区分歧视经历。专门关注种族歧视，并考虑纵向大脑结果，可能有助于我们理解歧视在解释非裔美国老年人中 ADRD 发病率不成比例方面的作用。
共有 221 名非裔美国老年人参加了华盛顿高地-因伍德哥伦比亚老龄化项目，他们在一个时间点完成了多种歧视测量，在两个时间点完成了结构磁共振成像（MRI）扫描。日常歧视和终身歧视首先被定义为歧视的综合经历（无论归因如何），然后被定义为种族歧视本身。MRI 结果包括海马体和脑白质高信号（WMH）体积。潜在差异评分模型估计了四年内歧视测量与每个 MRI 结果之间的关联。
综合歧视（无论归因如何）与任何结果都没有关联。终身种族歧视与初始海马体体积较低有关。日常种族歧视与随时间的 WMH 积累速度较快有关。
种族歧视可能对非裔美国老年人的大脑老化有害，这可能导致他们痴呆症负担不成比例。按归因对歧视进行区分，可能会澄清大脑和认知老化方面的种族不平等研究，因为种族歧视似乎特别有害。
