Authors: Shu‐Ping Tsao, Jen‐Hau Chen, Hwa‐Lung Yu, Jeng‐Min Chiou, Ta‐Fu Chen, Liang‐Chuan Lai, Yen‐Ching Chen
Published: 2020-12-07
DOI: 10.1002/alz.041433
Source: Full article
AbstractBackgroundAmbient air pollution exposure has been related to cognitive impairment. Several studies have started to explore the association of particulate matter and nitrogen oxides with cognitive impairment, studies evaluated the effect of long‐term exposure to ozone(O3), carbon monoxide (CO) and sulfur dioxide (SO2) are sparse.MethodThis study is part of the ongoing Taiwan Initiative for Geriatric Epidemiological Research (TIGER). A total of 605 participants (Age 65+) were recruited from a teaching hospital in northern Taiwan in 2011 and followed up biennially. After exclusion and loss to follow‐up over 6 years, a total of 292 participants were included for analyses. Global cognition was assessed by Montreal Cognitive Assessment‐Taiwanese version; domain‐specific cognition (logical memory, attention, verbal fluency, and executive function) were assessed by a battery of neuropsychological tests. The data of three air pollutants (O3, CO and SO2) were obtained from 27 monitor stations of Taiwan Environmental Protection Administration (EPA) between 1993 and 2010. Air pollutants were tertiled into low, moderate, and high levels. Spatial‐Time Analysis Rendering with Bayesian Maximum Entropy was utilized to establish the spatial‐temporal model. Logistic regression model was utilized to assess the association of exposure to air pollutants and global or domain‐specific cognition over 6 years adjusting for important covariates.ResultThe 17‐year average level was 39.40ppb for 8‐hour O3, 1.47ppm for 8‐hour CO, and 4.70ppb for daily SO2, which were below the EPA standards. Exposure to high‐level O3 (>40.83 ppb) was associated with poor executive function [adjusted odds ratio (aOR)=2.14, 95% confidence interval (CI)=1.05‐4.35] compared with low‐level O3. No significant association was observed between O3 or CO and global cognition or other cognitive domains. SO2 were not associated with cognitive function over 6 years.ConclusionLong‐term (17 years) exposure to O3, CO and SO2 lower than the EPA standards showed significant association with cognitive domains in a 6‐year cohort of community‐dwelling older adults. Future revisions of air standards may need to consider epidemiologic studies exploring the relation between exposure to these air pollutants and cognitive impairment.