ISGlobal, Barcelona, Catalonia, Spain
Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
Environ Health Perspect. 2018 Jul 12;126(7):077003. doi: 10.1289/EHP2875. eCollection 2018 Jul.
Evidence on beneficial associations of green space with cognitive function in older adults is very scarce and mainly limited to cross-sectional studies.
We aimed to investigate the association between long-term residential surrounding greenness and cognitive decline.
This longitudinal study was based on three waves of data from the Whitehall II cohort, providing a 10-y follow-up (1997-1999 to 2007-2009) of 6,506 participants (45-68 y old) from the United Kingdom. Residential surrounding greenness was obtained across buffers of 500 and around the participants' residential addresses at each follow-up using satellite images on greenness (Normalized Difference Vegetation Index; NDVI) from a summer month in every follow-up period. Cognitive tests assessed reasoning, short-term memory, and verbal fluency. The cognitive scores were standardized and summarized in a global cognition -score. To quantify the impact of greenness on repeated measurements of cognition, linear mixed effect models were developed that included an interaction between age and the indicator of greenness, and controlled for covariates including individual and neighborhood indicators of socioeconomic status (SES).
In a fully adjusted model, an interquartile range (IQR) increase in NDVI was associated with a difference in the global cognition z-score of 0.020 [95% confidence interval (CI): 0.003, 0.037; =0.02] in the 500-m buffer and of 0.021 (95% CI: 0.003, 0.039; =0.02) in the 1,000-m buffer over 10 y. The associations with cognitive decline over the study period were stronger among women than among men.
Higher residential surrounding greenness was associated with slower cognitive decline over a 10-y follow-up period in the Whitehall II cohort of civil servants. https://doi.org/10.1289/EHP2875.
关于绿色空间与老年人认知功能有益关联的证据非常有限，且主要限于横断面研究。
我们旨在研究长期居住环境绿色度与认知能力下降之间的关系。
本纵向研究基于英国 Whitehall II 队列的 3 个时间点的数据，对 6506 名参与者（45-68 岁）进行了 10 年随访（1997-1999 年至 2007-2009 年）。在每个随访期的夏季，使用卫星图像获取参与者居住地址周围 500m 缓冲区和 1000m 缓冲区的居住环境绿色度（归一化植被指数；NDVI）。认知测试评估推理、短期记忆和语言流畅性。将认知评分标准化并总结为一个整体认知评分。为了量化绿色度对认知重复测量的影响，我们建立了线性混合效应模型，该模型包括年龄与绿色度指标之间的相互作用，并控制了包括个体和邻里社会经济地位（SES）指标在内的协变量。
在完全调整模型中，NDVI 的四分位距（IQR）每增加一个单位，与居住环境 500m 缓冲区的整体认知 z 评分差值为 0.020[95%置信区间（CI）：0.003，0.037；=0.02]，1000m 缓冲区的整体认知 z 评分差值为 0.021（95% CI：0.003，0.039；=0.02），随访时间为 10 年。在研究期间，女性的认知衰退速度比男性更快。
在 Whitehall II 队列中，较高的居住环境绿色度与公务员 10 年随访期间认知能力下降速度较慢有关。https://doi.org/10.1289/EHP2875.
