Chaar Dima L, Tu Le, Moore Kari, Du Jiacong, Opsasnick Lauren A, Ratliff Scott M, Mosley Thomas H, Kardia Sharon L R, Zhao Wei, Zhou Xiang, Diez Roux Ana V, Faruque Fazlay S, Butler Kenneth R, Smith Jennifer A
Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
Department of Preventive Medicine, John D. Bower School of Population Health, University of Mississippi Medical Center, Jackson, USA.
BMC Med. 2025 Jan 13;23(1):15. doi: 10.1186/s12916-024-03845-7.
Since older adults spend significant time in their neighborhood environment, environmental factors such as neighborhood socioeconomic disadvantage, high racial segregation, low healthy food availability, low access to recreation, and minimal social engagement may have adverse effects on cognitive function and increase susceptibility to dementia. DNA methylation, which is associated with neighborhood characteristics as well as cognitive function and white matter hyperintensity (WMH), may act as a mediator between neighborhood characteristics and neurocognitive outcomes.
In this study, we examined whether DNA methylation in peripheral blood leukocytes mediates the relationship between neighborhood characteristics and cognitive function (N = 542) or WMH (N = 466) in older African American (AA) participants without preliminary evidence of dementia from the Genetic Epidemiology Network of Arteriopathy (GENOA).
For a 1-mile buffer around a participant's residence, each additional fast food destination or unfavorable food store with alcohol per square mile was nominally associated with a 0.05 (95%CI: 0.01, 0.09) and a 0.04 (0.00, 0.08) second improvement in visual conceptual tracking score, respectively. Also, each additional alcohol drinking place per square mile was nominally associated with a 0.62 (0.05, 1.19) word increase in delayed recall score, indicating better memory function (all p < 0.05). Neighborhood characteristics were not associated with WMH. We did not find evidence that DNA methylation mediates the observed associations between neighborhood characteristics and cognitive function.
The presence of fast food destinations and unfavorable food stores with alcohol was associated cognitive measures, possibly due to greater social interaction provided in these venues. However, replication of these findings is necessary. Further examination of the potential pathways between the neighborhood environment and cognitive function/WMH may allow the development of potential behavioral, infrastructural, and pharmaceutical interventions to facilitate aging in place and healthy brain aging in older adults, especially in marginal populations that are most at risk.
由于老年人在其邻里环境中度过大量时间，邻里社会经济劣势、高度种族隔离、健康食品供应不足、娱乐设施使用不便以及社交参与度低等环境因素可能会对认知功能产生不利影响，并增加患痴呆症的易感性。DNA甲基化与邻里特征以及认知功能和白质高信号（WMH）相关，可能在邻里特征与神经认知结果之间起中介作用。
在本研究中，我们调查了外周血白细胞中的DNA甲基化是否介导了邻里特征与认知功能（N = 542）或WMH（N = 466）之间的关系，研究对象为来自动脉病遗传流行病学网络（GENOA）的无痴呆初步证据的老年非裔美国人（AA）参与者。
对于参与者住所周围1英里的缓冲区，每增加一个快餐点或每平方英里有酒类销售的不良食品店，视觉概念追踪分数名义上分别提高0.05（95%CI：0.01，0.09）和0.04（0.00，0.08）。此外，每平方英里增加一个饮酒场所，延迟回忆分数名义上增加0.62（0.05，1.19）个单词，表明记忆功能更好（所有p < 0.05）。邻里特征与WMH无关。我们没有发现证据表明DNA甲基化介导了邻里特征与认知功能之间的观察到的关联。
快餐点和有酒类销售的不良食品店的存在与认知指标相关，可能是由于这些场所提供了更多的社交互动。然而，这些发现有必要进行重复验证。进一步研究邻里环境与认知功能/WMH之间的潜在途径，可能有助于开发潜在的行为、基础设施和药物干预措施，以促进老年人就地养老和健康的大脑衰老，特别是在风险最高的边缘人群中。
