Evidence Hub

All-cause mortality risk associated with long-term exposure to ambient PM2·5 in China: a cohort study

Tiantian Li, Yi Zhang, Jiaonan Wang, Dandan Xu, Z. Yin, Huashuai Chen, Yue-Bin Lv, Jiesi Luo et al.

Lancet Public Health, 2018

13 participants · 250 citations

Abstract

BACKGROUND

Evidence from cohort studies in North America and Europe indicates that long-term exposure to fine particulate matter (PM2·5) is associated with an increased mortality risk. However, this association has rarely been quantified at higher ambient concentrations. We estimated the hazard ratio (HR) for all-cause mortality from long-term exposure to PM2·5 in a well established Chinese cohort of older adults.

METHODS

The Chinese Longitudinal Healthy Longevity Survey (CLHLS) is a prospective cohort study of men and women aged 65 years and older enrolled in 2008 and followed up through 2014 for mortality events. We studied individuals for whom residential locations were available in 2008 for linkage to 1 km grids of PM2·5 concentrations, derived from satellite remote sensing. Cox proportional hazards models were used to estimate the effect of long-term exposure to PM2·5 on all-cause mortality, controlling for age, sex, smoking status, drinking status, physical activity, body-mass index, household income, marital status, and education. We then used our results to estimate premature mortality related to PM2·5 exposure in the population aged 65 years and older in China in 2010.

FINDINGS

13 344 individuals in the CLHLS cohort had data for all timepoints, yielding follow-up data for 49 440 person-years. In a 3-year window, these individuals were exposed to a median PM2·5 concentration of 50·7 μg/m3 (range 6·7-113·3). The overall HR for a 10 μg/m3 increase in this value was…

How strong is the evidence?

Evidence Hub reads this as a cohort study, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 13 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free