Systematic review and meta-analysis reveals increased morbidity and mortality from heat exposure in individuals with COPD, highlighting the need for targeted heat prevention strategies.
Key Points
To quantify the relationship between heat exposure and COPD morbidity and mortality while identifying sources of heterogeneity across existing studies.
Systematically searched PubMed, Embase, and Google Scholar to identify observational studies evaluating heat exposure and COPD-related health outcomes.
Synthesized data from 36 included studies using random-effects meta-analyses and a three-level model to account for non-independent effect estimates.
Conducted stratified analyses across outcome types, exposure definitions, lag windows, geographic scope, and air-pollution adjustment.
Heat exposure was associated with a higher overall COPD risk (pooled RR, 1.15; 95% CI: 1.09–1.21), with a stronger effect on mortality (RR, 1.26; 95% CI: 1.18–1.34) than morbidity (RR, 1.05; 95% CI: 1.01–1.09).
Heat-wave definitions and threshold-based criteria demonstrated greater pooled associations (both RR, 1.21) than continuous temperature metrics (RR, 1.05).
Positive associations persisted across multiple lag windows and were not substantially altered after adjusting for ambient air pollution.