Air Pollution Exposure and Cognitive Function in Taiwanese Older Adults: A Repeated Measurement Study.

Yuan-Ting C Lo,Yu-Hung Chang,Ya-Chi Lu,Senyeong Kao,Han-Bin Huang

doi:10.3390/ijerph16162976

Abstract

Studies related to air pollution exposure and neurocognitive disorders, specifically cognitive impairment, among older adults are limited. We investigated the association between short-term and long-term exposure to ambient air pollution (i.e., particulate matter with an aerodynamic diameter of <10 μm and ozone) and the effects of their interaction on cognitive function in a community-dwelling, free-living elderly population. Study participants were in a multiple-wave representative sample, namely the Taiwan Longitudinal Study on Aging (n = 2241). In four surveys between 1996 and 2007, their cognitive function was assessed using the Short Portable Mental Status Questionnaire (SPMSQ). We estimated air pollution from 1993 to 2007, including daily concentrations of PM10 and O3 from air quality monitoring stations, based on the administrative zone of each participant’s residence. Generalized linear mixed models were used to examine these associations after adjusting for covariates. We found that long-term exposure to PM10 and O3 was significantly associated with cognitive impairment (OR = 1.094, 95% CI: 1.020, 1.174 for PM10; OR = 1.878, 95% CI: 1.363, 2.560 for O3). The joint effect of exposure to PM10 and O3 was associated with cognitive impairment (p < 0.001). Co-exposure to ambient PM10 and O3 may deteriorate cognitive function in older adults.

Highlights

The world’s population is rapidly aging, and the proportion of older adults in the world is estimated to almost double from approximately 12% to 22% [1,2]
We found that exposure to O3 >25 ppb and PM10 >60 μg/m3 may increase the odds of moderate-to-severe cognitive impairment (OR = 2.012, 95% CI: 1.473, 2.746) as compared with lower O3 and PM10 exposure, with a statistically significant interaction term (p < 0.001)
We found that long-term co-exposure to PM10 and O3 may increase the risk of cognitive impairment

Summary

Introduction

The world’s population is rapidly aging, and the proportion of older adults in the world is estimated to almost double from approximately 12% to 22% [1,2]. More than 20% of adults aged 60 years and more have a neurological disorder [2]. Among the various types of pollution, ozone and particulate matter appear to be the most widespread and harmful airborne pollutants [5]. In vivo and in vitro studies have demonstrated that air pollutants, such as particulate matter (PM) and O3 , are neurotoxicants that can result in neurodevelopmental and neurological damage through inflammation and oxidative stress [6,7,8]. Experimental studies have reported that exposure to a mixture of PM and O3 can accelerate brain aging in dogs [9,10]

Methods

Results

Discussion

Conclusion