Abstract
Objectives
Evidence suggests long-term exposure to fine particulate matter air pollution (PM2.5) is associated with a higher risk of cognitive impairment especially among older adults. This study examines the relationship between PM2.5 exposure and cognitive function in China’s ageing population.
Method
We used longitudinal data from the China Health and Retirement Longitudinal Study (2011-2015) linked with historical PM2.5 concentrations (2000-2015) from remotely sensed satellite data. Growth curve models were applied to estimate associations between PM2.5 exposure (measured in intensity, duration, and a joint variable of intensity with duration for cumulative exposure) and cognitive function.
Results
Relative to the lowest exposure group, exposure in the second group of PM2.5 intensity (35-50 μg/m3) is associated with poorer cognitive function, but higher levels of PM2.5 appear to be associated with better cognitive function, indicating a U-shaped association. Similar patterns are seen for fully adjusted models of PM2.5 duration: the second group (13-60 months) is associated with worse cognitive function than the first group (0-12 months), but coefficients are non-significant in longer duration groups. Joint analysis of PM2.5 intensity with duration suggests that duration may play a more detrimental role in cognitive function than intensity. However, we do not find a statistically significant association between PM2.5 exposure and rate of cognitive decline.
Discussion
Our findings are mixed and suggest that some categories of higher and longer exposure to PM2.5 are associated with poorer cognitive function, while that exposures do not hasten cognitive decline. However, more work is necessary to disentangle PM2.5 exposure from individuals’ background characteristics, particularly those jointly associated with cognitive function and urban living.
Evidence suggests long-term exposure to fine particulate matter air pollution (PM2.5) is associated with a higher risk of cognitive impairment especially among older adults. This study examines the relationship between PM2.5 exposure and cognitive function in China’s ageing population.
Method
We used longitudinal data from the China Health and Retirement Longitudinal Study (2011-2015) linked with historical PM2.5 concentrations (2000-2015) from remotely sensed satellite data. Growth curve models were applied to estimate associations between PM2.5 exposure (measured in intensity, duration, and a joint variable of intensity with duration for cumulative exposure) and cognitive function.
Results
Relative to the lowest exposure group, exposure in the second group of PM2.5 intensity (35-50 μg/m3) is associated with poorer cognitive function, but higher levels of PM2.5 appear to be associated with better cognitive function, indicating a U-shaped association. Similar patterns are seen for fully adjusted models of PM2.5 duration: the second group (13-60 months) is associated with worse cognitive function than the first group (0-12 months), but coefficients are non-significant in longer duration groups. Joint analysis of PM2.5 intensity with duration suggests that duration may play a more detrimental role in cognitive function than intensity. However, we do not find a statistically significant association between PM2.5 exposure and rate of cognitive decline.
Discussion
Our findings are mixed and suggest that some categories of higher and longer exposure to PM2.5 are associated with poorer cognitive function, while that exposures do not hasten cognitive decline. However, more work is necessary to disentangle PM2.5 exposure from individuals’ background characteristics, particularly those jointly associated with cognitive function and urban living.
| Original language | English |
|---|---|
| Article number | gbac162 |
| Pages (from-to) | 556-569 |
| Number of pages | 14 |
| Journal | Journals of Gerontology Series B: Psychological Sciences and Social Sciences |
| Volume | 78 |
| Issue number | 3 |
| Early online date | 10 Oct 2022 |
| DOIs | |
| Publication status | Published - 4 Mar 2023 |
Keywords
- Cognitive function
- Air pollution
- PM2.5
- Cumulative exposure
- Health disparities
Access to Document
- Hu_2022_JGSB_Long-termexposure_CC
Copyright © The Author(s) 2022. Published by Oxford University Press on behalf of The Gerontological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.