Supplementary Material for: No consistent evidence that ageism is linked to biological aging status in the US Health and Retirement Study

Introduction: Ageism, defined as stereotype, prejudice, and discrimination against people based on their age, has been shown to have unfavorable impacts on health. While discrimination has often been shown to negatively impact health, whether ageism might accelerate biological aging itself is unclear.
Methods: We conducted secondary analyses of the Health and Retirement Study (HRS, 2008, 2012 and 2016 waves). Ageism was estimated using Self-Perception of Aging (SPA) and Perceived Age Discrimination (PAD). Other types of discrimination (e.g., racism, sexism) were also considered. The Everyday Discrimination Scale was used to assess PAD and other types of discrimination. Biological aging was measured through homeostatic dysregulation (HD, n=3443, 2016 wave, six measures), epigenetic age (n=1484, 2016 wave, five measures), and telomere length (n=1981, 2008 wave). Biological aging measures were modeled as a function of ageism within and across waves.
Results: Within waves, SPA score was associated with some elevated HD (e.g., β = 0.11, p < 0.001, quantified by 44 biomarkers) and epigenetic age indices (e.g., β = 0.61, p < 0.001, Hannum Epi Age). After controlling for comorbidities and social participation, these variables were no longer associated. Effects were similar but weaker in predicting 2016 biological aging from SPA in 2008 and 2012. PAD was not associated with biological aging measures, in contrast to other types of discrimination, which were.
Conclusions: We found no consistent evidence linking ageism to biological aging status. Further research should investigate why; potentially, ageism has less time to become biologically embedded, compared to racism and sexism, which might be experienced throughout one’s life, but measurement challenges could also be present.

引言：年龄歧视（Ageism）被定义为基于年龄对个体产生的刻板印象、偏见与歧视，已有研究证实其对健康存在不利影响。尽管各类歧视通常会对健康产生负面影响，但年龄歧视是否会加速生理衰老进程，目前尚不明确。
方法：本研究对健康与退休研究（Health and Retirement Study, HRS）2008、2012及2016年的三波追踪数据进行了二次分析。年龄歧视通过老年自我感知量表（Self-Perception of Aging, SPA）与感知年龄歧视量表（Perceived Age Discrimination, PAD）进行评估，同时纳入了种族歧视、性别歧视等其他类型的歧视指标。本研究采用日常歧视量表（Everyday Discrimination Scale）对PAD及其他类型的歧视进行测评。生理衰老的衡量维度包括：稳态失调（homeostatic dysregulation, HD，2016年波次，样本量n=3443，共6项检测指标）、表观遗传年龄（epigenetic age，2016年波次，样本量n=1484，共5项检测指标）以及端粒长度（telomere length，2008年波次，样本量n=1981）。研究将生理衰老指标作为不同波次内及跨波次年龄歧视的因变量进行建模分析。
结果：在同一波次内，SPA评分与部分升高的稳态失调指标（如通过44种生物标志物量化的指标，β=0.11，p<0.001）及表观遗传年龄指标（如Hannum表观遗传年龄，β=0.61，p<0.001）存在显著关联。在控制共病情况与社会参与度后，上述关联不再显著。以2008年及2012年的SPA评分预测2016年的生理衰老时，所得效应相似但强度较弱。与其他类型歧视不同，PAD与生理衰老指标未发现显著关联。
结论：本研究未发现年龄歧视与生理衰老状态存在一致性关联的可靠证据。未来研究可进一步探究其潜在原因：相较于可能贯穿终生的种族歧视与性别歧视，年龄歧视的暴露时长可能较短，难以在生理层面产生持久嵌入效应；此外，测量方法本身也可能存在局限性。