ArticleEnvironmental health perspectives2019
The Role of Humidity in Associations of High Temperature with Mortality: A Multicountry, Multicity Study.
Article in Environmental health perspectives, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 85 papers, 3 of them syntheses that pooled it.
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Who cites it
85 citing papers in PubMed, 3 syntheses or guidelines pooled it.
- Building the model: a review of input structures in extreme temperature-health.Environmental health : a global access science source · 2026Pooled it
- A Nationwide Comparative Analysis of Temperature-Related Mortality and Morbidity in Japan.Environmental health perspectives · 2023Pooled it
- Impacts of exposure to humidex on cardiovascular mortality: a multi-city study in Southwest China.BMC public health · 2023Pooled it
- Best-fit heat stress metric for modelling the heat-mortality relation across climatically distinct subregions of Southern California.Environmental research · 2026Article
- [Environmental relative humidity, frailty, and risk of incident stroke among middle-aged and older adults in China: A prospective cohort study].Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences · 2026Article
- Nighttime Cold Stress and Cardiovascular Emergency Hospitalizations: A Time-Series Analysis by Sex and Age in a Subtropical City.Journal of the American Heart Association · 2026Article
- Cause-specific heat-related mortality in Rio de Janeiro city: Comparing exposure metrics and the role of exposure duration.Environmental epidemiology (Philadelphia, Pa.) · 2026Article
- Humidity may amplify the temperature-related health risks in the context of climate change.Scientific reports · 2026Article
- Mortality risk associated with heatwave exposure based on daily maximum, minimum, and combined temperature thresholds.European journal of public health · 2026Article
- Heat during Pregnancy and Reduced Fetal Growth: Critical Windows of Exposure and the Intertwined Role of Air Pollution, Vegetation, and Social Stressors.Environmental science & technology · 2026Article
- Exploring 130 years of temperature-related mortality in the city of Madrid.Scientific reports · 2026Article
- Differential impacts of long-term exposure to ozone pollution on mortality in patients with hemorrhagic versus ischemic stroke: a retrospective cohort study.BMC public health · 2026Article
- Coordinating extreme-heat adaptation at mega-sporting events: early warning and cost sharing in a multi-actor differential game.Frontiers in public health · 2026Article
- Spatiotemporal Trends in Chronic Kidney Disease Mortality and Its Association with Low Temperature in the United States (1999-2023).International journal of nephrology and renovascular disease · 2026Article
- Climate change health risks and workplace protective strategies for construction workers.Scientific reports · 2025Article
- Does humidity matter? Prenatal heat and child health in South Asia.Science advances · 2025Article
- Ten new insights in climate science 2024.One earth (Cambridge, Mass.) · 2025Review
- Comparing the Role of Relative and Absolute Humidity in Heat-Related Mortality: A Case Time-Series Study in South Korea.Environmental health perspectives · 2025Article
- Evaluating compliance with HeatSuite for monitoring in situ physiological and perceptual responses and personal environmental exposure.NPJ digital medicine · 2025Article
- Estimating future heat-related and cold-related mortality under climate change, demographic and adaptation scenarios in 854 European cities.Nature medicine · 2025Article
25 more citing papers are in PubMed but not listed here.
Corrections and comments
- Erratum issued
Authors and funding
40 authors.
Funding
Abstract
backgroundThere is strong experimental evidence that physiologic stress from high temperatures is greater if humidity is higher. However, heat indices developed to allow for this have not consistently predicted mortality better than dry-bulb temperature.
objectivesWe aimed to clarify the potential contribution of humidity an addition to temperature in predicting daily mortality in summer by using a large multicountry dataset.
methodsIn 445 cities in 24 countries, we fit a time-series regression model for summer mortality with a distributed lag nonlinear model (DLNM) for temperature (up to lag 3) and supplemented this with a range of terms for relative humidity (RH) and its interaction with temperature. City-specific associations were summarized using meta-analytic techniques.
resultsAdding a linear term for RH to the temperature term improved fit slightly, with an increase of 23% in RH (the 99th percentile anomaly) associated with a 1.1% [95% confidence interval (CI): 0.8, 1.3] decrease in mortality. Allowing curvature in the RH term or adding terms for interaction of RH with temperature did not improve the model fit. The humidity-related decreased risk was made up of a positive coefficient at lag 0 outweighed by negative coefficients at lags of 1-3 d. Key results were broadly robust to small model changes and replacing RH with absolute measures of humidity. Replacing temperature with apparent temperature, a metric combining humidity and temperature, reduced goodness of fit slightly. DISCUSSION: The absence of a positive association of humidity with mortality in summer in this large multinational study is counter to expectations from physiologic studies, though consistent with previous epidemiologic studies finding little evidence for improved prediction by heat indices. The result that there was a small negative average association of humidity with mortality should be interpreted cautiously; the lag structure has unclear interpretation and suggests the need for future work to clarify. https://doi.org/10.1289/EHP5430.
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