University of Washington, Seattle, WA, USA.
Johns Hopkins University, Baltimore, MD, USA.
Environ Health. 2022 Jan 15;21(1):14. doi: 10.1186/s12940-022-00830-6.
Research suggests that greenspace may confer neurocognitive benefits. This study examines whether residential greenspace is associated with risk of dementia among older adults.
Greenspace exposure was computed for 3047 participants aged 75 years and older enrolled in the Gingko Evaluation of Memory Study (GEMS) across four U.S. sites that prospectively evaluated dementia and its subtypes, Alzheimer's disease (AD), vascular dementia (VaD), and mixed pathologies, using neuropsychiatric evaluations between 2000 and 2008. After geocoding participant residences at baseline, three greenspace metrics-Normalized Difference Vegetative Index, percent park overlap within a 2-km radius, and linear distance to nearest park-were combined to create a composite residential greenspace measure categorized into tertiles. Cox proportional hazards models estimated the associations between baseline greenspace and risk of incident all-cause dementia, AD, and Mixed/VaD.
Compared to low residential greenspace, high residential greenspace was associated with a reduced risk of dementia (HR = 0.76 95% CI: 0.59,0.98) in models adjusted for multiple covariates. After additional adjustment for behavioral characteristics, Apolipoprotein E ɛ4 status, and other covariates, the association was slightly attenuated (HR = 0.82; 95% CI:0.63,1.06). Those exposed to medium levels of greenspace also had 28% lower risk (HR = 0.72; CI: 0.55, 0.95) of dementia compared to those with low greenspace in adjusted models. Subtype associations between high residential greenspace and AD were not statistically significant. Greenspace was not found to be significantly associated with mixed/vascular pathologies.
This study showed evidence for an association between residential greenspace and all-cause dementia among older adults. Future research with larger sample size, precise characterization of different dementia subtypes, and assessment of residential greenspace earlier in life may help clarify the role between exposure to greenspace and dementia risk.
研究表明，绿色空间可能对神经认知有益。本研究旨在探讨居住环境中的绿色空间与老年人痴呆风险之间的关系。
在银杏评估记忆研究（GEMS）中，共有 3047 名年龄在 75 岁及以上的参与者参与了这项研究，该研究在美国四个地点进行，前瞻性地评估了痴呆及其亚型（阿尔茨海默病（AD）、血管性痴呆（VaD）和混合病理），使用神经精神病学评估在 2000 年至 2008 年之间进行。在基线时对参与者居住地进行地理编码后，将三个绿色空间指标（归一化差异植被指数、2 公里半径内公园重叠百分比和到最近公园的线性距离）结合起来，创建一个分类为三分位的综合居住绿色空间度量。Cox 比例风险模型估计了基线绿色空间与全因痴呆、AD 和混合/血管性痴呆的发病风险之间的关系。
与低居住绿色空间相比，高居住绿色空间与痴呆风险降低相关（调整多个协变量后的 HR=0.76，95%CI：0.59，0.98）。在进一步调整行为特征、载脂蛋白 Eɛ4 状态和其他协变量后，该关联略有减弱（HR=0.82；95%CI：0.63，1.06）。与低绿色空间相比，暴露于中等水平绿色空间的人痴呆风险也降低了 28%（调整模型中的 HR=0.72；CI：0.55，0.95）。在调整后的模型中，高居住绿色空间与 AD 之间的亚型关联没有统计学意义。绿色空间与混合/血管性病变之间没有显著关联。
本研究表明，老年人居住环境中的绿色空间与全因痴呆之间存在关联。未来的研究需要更大的样本量、更精确的不同痴呆亚型特征描述以及更早评估居住环境中的绿色空间，以帮助阐明暴露于绿色空间与痴呆风险之间的关系。
