Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
PLoS One. 2023 Jul 5;18(7):e0287112. doi: 10.1371/journal.pone.0287112. eCollection 2023.
Racial disparities in many aging-related health outcomes are persistent and pervasive among older Americans, reflecting accelerated biological aging for Black Americans compared to White, known as weathering. Environmental determinants that contribute to weathering are poorly understood. Having a higher biological age, measured by DNA methylation (DNAm), than chronological age is robustly associated with worse age-related outcomes and higher social adversity. We hypothesize that individual socioeconomic status (SES), neighborhood social environment, and air pollution exposures contribute to racial disparities in DNAm aging according to GrimAge and Dunedin Pace of Aging methylation (DPoAm). We perform retrospective cross-sectional analyses among 2,960 non-Hispanic participants (82% White, 18% Black) in the Health and Retirement Study whose 2016 DNAm age is linked to survey responses and geographic data. DNAm aging is defined as the residual after regressing DNAm age on chronological age. We observe Black individuals have significantly accelerated DNAm aging on average compared to White individuals according to GrimAge (239%) and DPoAm (238%). We implement multivariable linear regression models and threefold decomposition to identify exposures that contribute to this disparity. Exposure measures include individual-level SES, census-tract-level socioeconomic deprivation and air pollution (fine particulate matter, nitrogen dioxide, and ozone), and perceived neighborhood social and physical disorder. Race and gender are included as covariates. Regression and decomposition results show that individual-level SES is strongly associated with and accounts for a large portion of the disparity in both GrimAge and DPoAm aging. Higher neighborhood deprivation for Black participants significantly contributes to the disparity in GrimAge aging. Black participants are more vulnerable to fine particulate matter exposure for DPoAm, perhaps due to individual- and neighborhood-level SES, which may contribute to the disparity in DPoAm aging. DNAm aging may play a role in the environment "getting under the skin", contributing to age-related health disparities between older Black and White Americans.
在许多与衰老相关的健康结果方面，美国老年人中存在着明显的种族差异，这反映了与白种人相比，黑种人的生物学衰老速度更快，这种现象被称为“老化”。造成这种“老化”的环境决定因素尚未得到充分理解。通过 DNA 甲基化（DNAm）测量的生物学年龄比实际年龄大，与与年龄相关的不良结果和更高的社会逆境高度相关。我们假设，个体的社会经济地位（SES）、邻里社会环境和空气污染暴露会根据 GrimAge 和 Dunedin 衰老速度的甲基化（DPoAm）导致 DNAm 衰老方面的种族差异。我们对参加健康与退休研究的 2960 名非西班牙裔参与者（82%为白人，18%为黑人）进行了回顾性横断面分析，这些参与者在 2016 年的 DNAm 年龄与调查回复和地理数据相关联。DNAm 年龄定义为 DNAm 年龄回归到实际年龄后的残差。根据 GrimAge（239%）和 DPoAm（238%），我们观察到黑人个体的 DNAm 衰老速度明显快于白人个体。我们实施了多变量线性回归模型和三分分解法，以确定导致这种差异的暴露因素。暴露因素包括个体 SES、普查区社会经济剥夺程度和空气污染（细颗粒物、二氧化氮和臭氧）以及感知到的邻里社会和物理混乱程度。种族和性别被纳入协变量。回归和分解结果表明，个体 SES 与 GrimAge 和 DPoAm 衰老的差异密切相关，并解释了其中的大部分差异。黑人参与者所处的邻里剥夺程度较高，这对 GrimAge 衰老的差异有显著贡献。对于 DPoAm，黑种人更容易受到细颗粒物的暴露，这可能是由于个体和邻里 SES 水平较低，这可能导致了 DPoAm 衰老的差异。DNAm 衰老可能在环境“穿透皮肤”中发挥作用，导致美国老年黑人和白人之间与年龄相关的健康差异。
