Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, United States of America.
Department of Medicine, Division of Geriatric Medicine and Gerontology, Johns Hopkins School of Medicine, United States of America.
Sci Total Environ. 2024 Nov 1;949:175149. doi: 10.1016/j.scitotenv.2024.175149. Epub 2024 Jul 29.
Social cohesion can reduce stress, increase social interaction, and improve cognitive reserve. These social mechanisms may modify the effects of air pollution on dementia risk. This cohort study examines the potential moderating effect of social cohesion on associations between joint air pollution exposure and incident dementia leveraging data from 5112 community-dwelling adults ≥65 years of age enrolled in the National Health and Aging Trends Study (NHATS). Study participants were enrolled in 2011 and followed through 2018. We assigned 2010 residential census tract-level exposures to five air pollutants, particulate matter (PM) ≤ 10 μm in diameter, PM ≤ 2.5 μm in diameter, carbon monoxide, nitric oxide, and nitrogen dioxide, using the US Environmental Protection Agency's Community Multiscale Air Quality Modeling System. Dementia status was determined based on self- or proxy-reported dementia diagnosis or "probable dementia" according to NHATS cognitive screening tools. Participants' self-rated neighborhood social cohesion was evaluated based on three questions: neighbors knowing each other, being helpful, and being trustworthy. Social cohesion was dichotomized at the median into high vs low social cohesion. Associations between air pollutants and incident dementia were assessed using quantile g-computation Cox proportional hazard models and stratified by high vs low social cohesion, adjusting for age, sex, education, partner status, urbanicity, annual income, race and ethnicity, years lived at current residence, neighborhood disadvantage index, and tract segregation. High social cohesion (HR = 1.20, 95 % CI = 0.98, 1.47) and air pollution (HR = 1.08, 95 % CI = 0.92, 1.28) were not associated with incident dementia alone. However, when stratified, greater joint air pollution exposure increased dementia risk among participants at low (HR = 1.34, 95 % CI = 1.04, 1.72), but not high (HR = 1.00, 95 % CI = 0.93, 1.06) social cohesion. Air pollution was a risk factor for dementia only when reported social cohesion was low, suggesting that social interaction may play a protective role, mitigating dementia risk via air pollution exposure.
社会凝聚力可以减轻压力、增加社会互动并提高认知储备。这些社会机制可能会改变空气污染对痴呆症风险的影响。本队列研究利用来自国家健康老龄化趋势研究（NHATS）的 5112 名≥65 岁的社区居住成年人的数据，检验了社会凝聚力对联合空气污染暴露与新发痴呆症之间关联的潜在调节作用。研究参与者于 2011 年入组，并随访至 2018 年。我们使用美国环境保护署的社区多尺度空气质量建模系统，为 2010 年居住的普查区层面暴露分配了五种空气污染物的暴露量，包括粒径为≤10μm 的颗粒物（PM）、粒径为≤2.5μm 的颗粒物、一氧化碳、一氧化氮和二氧化氮。痴呆症的状况是根据自我报告或代理报告的痴呆症诊断或 NHATS 认知筛查工具确定的“可能的痴呆症”来确定的。参与者的自我评估邻里社会凝聚力基于三个问题进行评估：邻居相互了解、互相帮助和值得信任。社会凝聚力以中位数分为高或低社会凝聚力。使用分位数 g 计算 Cox 比例风险模型评估空气污染物与新发痴呆症之间的关联，并根据高或低社会凝聚力进行分层，调整年龄、性别、教育程度、伴侣状况、城市状况、年收入、种族和民族、在当前居住地居住的年限、邻里劣势指数和普查区隔离度。高社会凝聚力（HR=1.20，95%CI=0.98，1.47）和空气污染（HR=1.08，95%CI=0.92，1.28）单独与新发痴呆症无关。然而，分层后，在低社会凝聚力（HR=1.34，95%CI=1.04，1.72）而非高社会凝聚力（HR=1.00，95%CI=0.93，1.06）的参与者中，更大的联合空气污染暴露增加了痴呆症风险。只有当报告的社会凝聚力较低时，空气污染才是痴呆症的危险因素，这表明社会互动可能发挥保护作用，通过空气污染暴露降低痴呆症风险。
