Assessment of extreme heat and hospitalizations to inform early warning systems
Open Access
- 4 March 2019
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 116 (12), 5420-5427
- https://doi.org/10.1073/pnas.1806393116
Abstract
Heat early warning systems and action plans use temperature thresholds to trigger warnings and risk communication. In this study, we conduct multistate analyses, exploring associations between heat and all-cause and cause-specific hospitalizations, to inform the design and development of heat–health early warning systems. We used a two-stage analysis to estimate heat–health risk relationships between heat index and hospitalizations in 1,617 counties in the United States for 2003–2012. The first stage involved a county-level time series quasi-Poisson regression, using a distributed lag nonlinear model, to estimate heat–health associations. The second stage involved a multivariate random-effects meta-analysis to pool county-specific exposure–response associations across larger geographic scales, such as by state or climate region. Using results from this two-stage analysis, we identified heat index ranges that correspond with significant heat-attributable burden. We then compared those with the National Oceanic and Atmospheric Administration National Weather Service (NWS) heat alert criteria used during the same time period. Associations between heat index and cause-specific hospitalizations vary widely by geography and health outcome. Heat-attributable burden starts to occur at moderately hot heat index values, which in some regions are below the alert ranges used by the NWS during the study time period. Locally specific health evidence can beneficially inform and calibrate heat alert criteria. A synchronization of health findings with traditional weather forecasting efforts could be critical in the development of effective heat–health early warning systems.Keywords
This publication has 40 references indexed in Scilit:
- Methods to Calculate the Heat Index as an Exposure Metric in Environmental Health ResearchEnvironmental Health Perspectives, 2013
- Modeling exposure–lag–response associations with distributed lag non‐linear modelsStatistics in Medicine, 2013
- Are heat warning systems effective?Environmental Health, 2013
- Reducing and meta-analysing estimates from distributed lag non-linear modelsBMC Medical Research Methodology, 2013
- Multivariate meta‐analysis for non‐linear and other multi‐parameter associationsStatistics in Medicine, 2012
- Effects of temperature on mortality in Chiang Mai city, Thailand: a time series studyEnvironmental Health, 2012
- Ambient Temperature and Morbidity: A Review of Epidemiological EvidenceEnvironmental Health Perspectives, 2012
- Summer Heat and Mortality in New York City: How Hot Is Too Hot?Environmental Health Perspectives, 2010
- The 2006 California Heat Wave: Impacts on Hospitalizations and Emergency Department VisitsEnvironmental Health Perspectives, 2009
- Quantifying heterogeneity in a meta-analysisStatistics in Medicine, 2002