Evidence on Vulnerability and Susceptibility to Health Effects Associated with Short-Term Exposure to Particulate Matter: Systematic Review and Meta Analysis

摘要

Background: While there is strong evidence that particulate matter (PM) affects health, less is known about whether some sub-populations face higher risk. There is no consensus on which individual- or community-level characteristics affect PM risk estimates and to what degree (i.e., effect modification). Aims: The goal of this work is to summarize the state of scientific evidence on effect modification of health effects for short-term exposure to particulate matter. Methods: We performed a systematic review of the scientific literature on effect modification for short-term exposure to PM and performed meta-analysis for mortality associations by age and sex. Results: We identified 108 papers that directly investigate factors that might modify mortality or hospital admission risks from short-term PM exposure. Results indicate strong, consistent evidence that the elderly experience higher risks; suggestive evidence that those with lower education, income, or employment status have higher risks; and weak evidence for higher risks for women. Meta-analysis showed statistically higher effects for older populations (0.64% [0.50, 0.80%] increase in mortality per 10 μg/m3 increase in PM10) than younger populations (0.37% [0.27, 0.48%]). For women, a 10 μg/m3 increase in PM10 was associated with a 0.55% [0.41, 0.70%] increase in mortality, whereas for men this increase was 0.50% [0.34, 0.65%]. Conclusions: Evidence indicates that some populations facing larger health burdens from airborne particles. Our synthesis on modifiers for PM effects can aid design of air quality policies and suggest directions for future research. Studies of biological mechanism could be informed by evidence of differential effects by population, such as by sex and pre-existing conditions.