Does ambient PM2.5 reduce the protective association of leisure-time physical activity with mortality? A systematic review, meta-analysis, and individual-level pooled analysis of cohort studies involving 1.5 million adults

作者：Po‐Wen Ku, Andrew Steptoe, Mark Hamer, Paola Zaninotto, Emmanuel Stamatakis, Ching‐Heng Lin, Bin Yu, Ulla Arthur Hvidtfeldt, Xiang Qian Lao, Hsien-Ho Lin, Wei‐Cheng Lo, Ole Raaschou‐Nielsen, Shengzhi Sun, Linwei Tian, Sufen Wang, Yiqian Zeng, Yunquan Zhang, Shang‐Ti Chen, Chien-Fong Huang, Yang Xia, Li‐Jung Chen · 发表于：BMC Medicine · 年份：2025 · DOI：10.1186/s12916-025-04496-y · 被引用次数：5 · 研究领域：Physical Activity and Health、Air Quality and Health Impacts、Health, Environment, Cognitive Aging

Abstract Background This study assessed whether higher levels of fine particulate matter (PM 2.5 ) reduce the protective effects of leisure-time physical activity (LTPA) on all-cause, cardiovascular, and cancer mortality, and explored the PM 2.5 threshold beyond which attenuation occurs. Methods We conducted two complementary investigations. First, a systematic review and meta-analysis (per PRISMA guidelines) identified eligible cohort studies from PubMed, Web of Science, Embase, and SPORTDiscus (from inception to 6 January 2025) that examined the independent or joint associations of LTPA and PM₂.₅ with mortality among adults (≥ 18 years). Second, an individual-level pooled analysis using harmonized data from three cohorts was performed using Cox regression modeling to assess the associations observed in the meta-analysis. Results In Study One, a total of seven cohort studies ( n = 1,515,094; deaths = 115,196) were included in the meta-analysis, revealing that the reduction in all-cause mortality risk diminished with higher PM 2.5 exposure. Meeting the recommended LTPA level (7.5–15 MET-h/week) reduced all-cause mortality risk by approximately 30% at PM 2.5 < 25 μg/m 3 but only 12–15% at 25 + μg/m 3 . Study Two (three cohorts; n = 869,038; deaths = 45,080) confirmed this pattern. Individuals meeting the recommended LTPA level (7.5–15 MET-h/week) had a lower risk of all-cause mortality compared to those in the highest-risk group (reference: < 1 MET-h/week and PM 2.5 : 35...