Abstract：
BACKGROUND: Air pollution is recognized as a modifiable risk factor for dementia, and recent evidence suggests that improving air quality could attenuate cognitive decline and reduce dementia risk. However, studies have yet to explore the effects of improved air quality on brain structures. This study aims to investigate the impact of air pollution reduction on cognitive functions and structural brain differences among cognitively normal older adults.
METHODS: Four hundred and thirty-one cognitively normal older adults were from the Epidemiology of Mild Cognitive Impairment study in Taiwan (EMCIT), a community-based cohort of adults aged 60 and older, between year 2017- 2021. Annual concentrations of PM2.5, NO2, O3, and PM10 at participants\' residential addresses during the 10 years before enrollment were estimated using ensemble mixed spatial models. The yearly rate of change (slope) in air pollutants was estimated for each participant. Cognitive functions and structural brain images were collected during enrollment. The relationships between the rate of air pollution change and cognitive functions were examined using linear regression models. For air pollutants with significant findings in relation to cognitive function, we further explored the association with brain structure.
RESULTS: Overall, all pollutant concentrations, except O3, decreased over the 10-year period. The yearly rates of change (slopes) in PM2.5 and NO2 were correlated with better attention (PM2.5: r = -0.1, p = 0.047; NO2: r = -0.1, p = 0.03) and higher white matter integrity in several brain regions. These regions included anterior thalamic radiation, superior longitudinal fasciculus, inferior longitudinal fasciculus, corticospinal tract, and inferior fronto-occipital fasciculus.
CONCLUSIONS: Greater rate of reduction in air pollution was associated with better attention and attention-related white matter integrity. These results provide insight into the mechanism underlying the relationship between air pollution, brain health, and cognitive aging among older adults.
METHODS: Four hundred and thirty-one cognitively normal older adults were from the Epidemiology of Mild Cognitive Impairment study in Taiwan (EMCIT), a community-based cohort of adults aged 60 and older, between year 2017- 2021. Annual concentrations of PM2.5, NO2, O3, and PM10 at participants\' residential addresses during the 10 years before enrollment were estimated using ensemble mixed spatial models. The yearly rate of change (slope) in air pollutants was estimated for each participant. Cognitive functions and structural brain images were collected during enrollment. The relationships between the rate of air pollution change and cognitive functions were examined using linear regression models. For air pollutants with significant findings in relation to cognitive function, we further explored the association with brain structure.
RESULTS: Overall, all pollutant concentrations, except O3, decreased over the 10-year period. The yearly rates of change (slopes) in PM2.5 and NO2 were correlated with better attention (PM2.5: r = -0.1, p = 0.047; NO2: r = -0.1, p = 0.03) and higher white matter integrity in several brain regions. These regions included anterior thalamic radiation, superior longitudinal fasciculus, inferior longitudinal fasciculus, corticospinal tract, and inferior fronto-occipital fasciculus.
CONCLUSIONS: Greater rate of reduction in air pollution was associated with better attention and attention-related white matter integrity. These results provide insight into the mechanism underlying the relationship between air pollution, brain health, and cognitive aging among older adults.
摘要：
背景：空气污染被认为是痴呆的可改变的危险因素，最近的证据表明，改善空气质量可以减轻认知能力下降并降低痴呆风险。然而,研究尚未探索改善空气质量对大脑结构的影响。这项研究旨在调查减少空气污染对认知正常老年人认知功能和大脑结构差异的影响。
方法：来自台湾轻度认知障碍流行病学研究（EMCIT）的4131名认知正常的老年人，以社区为基础的60岁及以上的成年人队列，在2017-2021年之间。使用集合混合空间模型估算了入组前10年参与者居住地址中PM2.5，NO2，O3和PM10的年浓度。估计了每个参与者的空气污染物的年变化率（斜率）。在招募期间收集认知功能和结构性脑图像。使用线性回归模型检查了空气污染变化率与认知功能之间的关系。对于与认知功能相关的显著发现的空气污染物，我们进一步探讨了与大脑结构的关联。
结果：总体而言，所有污染物浓度，除O3外，10年期间下降。PM2.5和NO2的年变化率（斜率）与更好的注意力（PM2.5：r=-0.1，p=0.047；NO2：r=-0.1，p=0.03）和较高的白质完整性相关。这些区域包括前丘脑辐射，上纵束，下纵束，皮质脊髓束，和下额枕骨束。
结论：空气污染减少率更高与更好的注意力和与注意力相关的白质完整性有关。这些结果提供了对空气污染之间关系的潜在机制的洞察力，大脑健康,和老年人的认知老化。
方法：来自台湾轻度认知障碍流行病学研究（EMCIT）的4131名认知正常的老年人，以社区为基础的60岁及以上的成年人队列，在2017-2021年之间。使用集合混合空间模型估算了入组前10年参与者居住地址中PM2.5，NO2，O3和PM10的年浓度。估计了每个参与者的空气污染物的年变化率（斜率）。在招募期间收集认知功能和结构性脑图像。使用线性回归模型检查了空气污染变化率与认知功能之间的关系。对于与认知功能相关的显著发现的空气污染物，我们进一步探讨了与大脑结构的关联。
结果：总体而言，所有污染物浓度，除O3外，10年期间下降。PM2.5和NO2的年变化率（斜率）与更好的注意力（PM2.5：r=-0.1，p=0.047；NO2：r=-0.1，p=0.03）和较高的白质完整性相关。这些区域包括前丘脑辐射，上纵束，下纵束，皮质脊髓束，和下额枕骨束。
结论：空气污染减少率更高与更好的注意力和与注意力相关的白质完整性有关。这些结果提供了对空气污染之间关系的潜在机制的洞察力，大脑健康,和老年人的认知老化。
