Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA.
Demography. 2024 Aug 1;61(4):1023-1041. doi: 10.1215/00703370-11466635.
Past research suggests that resilience to health hazards increases with age, potentially because less resilient individuals die at earlier ages, leaving behind their more resilient peers. Using lifetime cigarette smoking as a model health hazard, we examined whether accelerated epigenetic aging (indicating differences in the speed of individuals' underlying aging process) helps explain age-related resilience in a nationally representative sample of 3,783 older U.S. adults from the Health and Retirement Study. Results of mediation moderation analyses indicated that participants aged 86 or older showed a weaker association between lifetime cigarette smoking and mortality relative to participants aged 76-85 and a weaker association between smoking and multimorbidity relative to all younger cohorts. This moderation effect was mediated by a reduced association between smoking pack-years and epigenetic aging. This research helps identify subpopulations of particularly resilient individuals and identifies epigenetic aging as a potential mechanism explaining this process. Interventions in younger adults could utilize epigenetic aging estimates to identify the most vulnerable individuals and intervene before adverse health outcomes, such as chronic disease morbidity or mortality, manifest.
过去的研究表明，对健康危害的适应能力会随着年龄的增长而增强，这可能是因为适应能力较弱的个体在较早的年龄就去世了，留下了他们更有适应能力的同龄人。本研究使用终生吸烟作为健康危害的模型，通过对来自美国健康与退休研究的 3783 名具有代表性的老年成年人进行分析，考察了加速的表观遗传衰老（表明个体潜在衰老过程的速度差异）是否有助于解释与年龄相关的适应能力。中介调节分析的结果表明，与 76-85 岁的参与者相比，86 岁或以上的参与者终生吸烟与死亡率之间的关联较弱，与所有年轻队列相比，吸烟与多种疾病之间的关联较弱。这种调节效应是通过吸烟包年数与表观遗传衰老之间的关联减弱来介导的。这项研究有助于确定特别有适应能力的个体亚群，并确定表观遗传衰老作为解释这一过程的潜在机制。针对年轻人的干预措施可以利用表观遗传衰老的估计来识别最脆弱的个体，并在出现慢性疾病发病率或死亡率等不良健康后果之前进行干预。
