Iyer Hari S, Cheng Iona, Opara Chidinma, Lin Katherine, Zeinomar Nur, Le Marchand Loïc, Wilkens Lynne, Shariff-Marco Salma, Conti David V, Haiman Christopher A, Gomez Scarlett L, Rebbeck Timothy R
Section of Cancer Epidemiology and Health Outcomes, Rutgers Cancer Institute, New Brunswick, New Jersey.
Department of Epidemiology and Biostatistics, University of California, San Francisco.
JAMA Netw Open. 2025 May 1;8(5):e2510016. doi: 10.1001/jamanetworkopen.2025.10016.
Although structural and social determinants of health (SSDH) have been consistently associated with health disparities, percentage African genetic ancestry (AGA) has been suggested as a risk factor associated with common diseases in Black populations. Appropriate use and interpretation of percentage AGA in understanding health disparities has been complicated by the fact that percentage AGA is correlated with genetic and nongenetic factors.
To evaluate associations of SSDH with mortality in the context of percentage AGA and how percentage AGA is correlated with SSDH.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study investigated data from the Multiethnic Cohort (MEC) Study, in which participants were enrolled from 1993 through 1996 and followed up until death or censoring on December 31, 2019. Participant data were analyzed between March and June 2023. The population-based sample was predominantly from Los Angeles County, California, consisting of self-identified Black adults aged 45 to 75 years who enrolled into the MEC Study; completed a baseline demographic, clinical, and lifestyle questionnaire; and provided biospecimens.
The Index of Concentration at the Extremes (ICE), capturing social polarization based on income and racial composition, and a neighborhood socioeconomic status (NSES) index were computed from the 1990 Census, scaled to county-specific quintiles, and linked to residential census tracts at study enrollment. Percentage AGA was estimated using 21 431 single-nucleotide variations based on similarity with African continental referent data.
Multivariable hazard ratios (HRs) for all-cause mortality were estimated from Cox models. Correlation of percentage AGA with SSDH measures was described.
After exclusions, 9685 participants were included (mean [SD] age, 61.0 [8.9] years; 5593 female [57.7%]), with a mean (SD) percentage AGA of 75.0% (14.0%). There were 5504 deaths over 204 463 person-years of follow-up. Comparing the most with least advantaged quintile, income ICE (adjusted HR [aHR], 1.30; 95% CI, 1.16-1.45) and NSES (aHR, 1.37, 95% CI, 1.20-1.56) were associated with lower all-cause mortality. Minimal changes were observed after adjusting for percentage AGA; for example, comparing the most with least advantaged quintile, NSES (aHR, 1.36; 95% CI, 1.19-1.55) remained associated with lower all-cause mortality. There was no association between percentage AGA and mortality after adjustment (aHR per 10-percentage point change in percentage AGA, 1.01; 95% CI, 0.99-1.03).
In this study, associations of SSDH with mortality persisted with adjustment for percentage AGA. Findings support the hypothesis that SSDH should be the primary factors to consider for eliminating health disparities.
尽管健康的结构和社会决定因素（SSDH）一直与健康差距相关，但非洲遗传血统百分比（AGA）被认为是与黑人人群常见疾病相关的一个风险因素。由于AGA百分比与遗传和非遗传因素相关，因此在理解健康差距时对AGA百分比的恰当使用和解释变得复杂。
在AGA百分比的背景下评估SSDH与死亡率之间的关联，以及AGA百分比与SSDH的相关性。
设计、背景和参与者：这项队列研究调查了多族裔队列（MEC）研究的数据，该研究的参与者于1993年至1996年入组，并随访至2019年12月31日死亡或失访。参与者数据于2023年3月至6月进行分析。该基于人群的样本主要来自加利福尼亚州洛杉矶县，由年龄在45至75岁之间、自我认定为黑人的成年参与者组成，他们参加了MEC研究；完成了一份基线人口统计学、临床和生活方式问卷；并提供了生物样本。
根据1990年人口普查计算出极端浓度指数（ICE），该指数基于收入和种族构成反映社会两极分化，以及邻里社会经济地位（NSES）指数，将其缩放到特定县的五分位数，并与研究入组时的居住普查区相关联。基于与非洲大陆参考数据的相似性，使用21431个单核苷酸变异估计AGA百分比。
通过Cox模型估计全因死亡率的多变量风险比（HR）。描述了AGA百分比与SSDH测量指标之间的相关性。
排除后，纳入了9685名参与者（平均[标准差]年龄为61.0[8.9]岁；5593名女性[57.7%]），AGA百分比的平均值（标准差）为75.0%（14.0%）。在204463人年的随访期间有5504人死亡。将最具优势的五分位数与最不具优势的五分位数进行比较，收入ICE（调整后HR[aHR]，1.30；95%置信区间，1.16 - 1.45）和NSES（aHR，1.37，95%置信区间，1.20 - 1.56）与较低的全因死亡率相关。在调整AGA百分比后观察到的变化最小；例如，将最具优势的五分位数与最不具优势的五分位数进行比较，NSES（aHR，1.36；95%置信区间，1.19 - 1.55）仍然与较低的全因死亡率相关。调整后AGA百分比与死亡率之间无关联（AGA百分比每变化10个百分点的aHR为1.01；95%置信区间，0.99 - 1.03）。
在本研究中，对AGA百分比进行调整后，SSDH与死亡率之间的关联仍然存在。研究结果支持以下假设，即SSDH应是消除健康差距时需考虑的主要因素。
