Climate Epidemiology

Climate change profoundly affects human health in multiple ways, including the direct health effects of ambient temperature and extreme weather events. Our research has advanced our understanding of how extreme temperatures can affect a comprehensive spectrum of diseases, including myocardial infarction (i.e., heart attack), unintentional injuries, and mental disorders. Our ongoing and future work will investigate the understudied climate-disease associations, including a new project on the associations between extreme precipitation, floods, drought, and childhood diarrhea.

In this study, we used a case-crossover analysis using 2,494 cases of non-fatal heart attack in Augsburg, Germany during the hot-weather months between 2001 and 2014. We found that heat-related non-fatal heart attack risk was elevated among people who use anti-platelet medication or beta-receptor blockers, but not among non-users, with significant differences between users and non-users. This association was stronger in younger patients without pre-existing coronary heart disease (a potential confounder) than in older patients (who had a higher prevalence of pre-existing coronary heart disease).

Published in: Nature Cardiovascular Research, 2022

Learn more about the Medications Tied to Heart Attack Risk During Very Hot Weather.

In this study, we employed a two-stage time series design with data from 446,807 deaths from 2015 to 2019 across 98 counties in North Carolina, and found that the health impacts of acute and fast flash floods, and days-long floods were fairly similar. Compared with the non-flooding days, the relative risk of deaths associated with flooding exposure significantly increased for total, non-accidental, and accidental mortality, respectively. Older adults aged 65 years old had a significantly higher risk increase in accidental mortality. More total deaths were attributable to non-flash floods and with multiple-day floods, and compared with one-day floods, multiple-day flood was associated with higher relative risks in total death and all non-accidental causes of death.

Published in: Nature Water, 2023

Learn more about the Human Health Costs of Exposure to Floods.

In this study, we analyzed cross-sectional health and flood data from 43 low- and middle-income countries and found that more severe flooding on a global level increases the risk of potentially life-threatening diarrhea among children under the age of five. Flood exposure was associated with increased diarrhea risk, with the highest odds ratio (OR) observed during the second to fourth weeks after floods began, and significant associations were observed only for extreme floods or floods lasting more than 2 weeks.

Published in JAMA Pediatrics, 2023

Learn more about the Severe flooding linked to increased diarrhea risk in children.

In this study, we applied a three-stage ensemble model to estimate daily mean Ta from satellite-based land surface temperature (Ts) over Sweden during 2001–2019 at a high spatial resolution of 1 × 1 km2. The ensemble model incorporated four base models, including a generalized additive model (GAM), a generalized additive mixed model (GAMM), and two machine learning models (random forest [RF] and extreme gradient boosting [XGBoost]). The ensemble model showed high performance with an overall R2 of 0.98 and a root mean square error of 1.38 °C in the ten-fold cross-validation.

Published in: Environ Res, 2022

This time-series study quantified the mortality burden attributable to heat and cold for a comprehensive spectrum of plausible diseases, including Alzheimer’s and dementia, myocardial infarction, stroke, hypertensive heart disease, chronic obstructive pulmonary disease, and diabetes.

Published in: Environment International. 2020.

In collaboration with Dr. Eun-hye Yoo at the State University of New York at Buffalo, our study reveals the adverse effects of heat on mental disorders (e.g. mood and anxiety disorders, schizophrenia, and dementia) in the New York State.

Published in: Science of the Total Environment, 2021.

Diarrhea is a leading killer of young children around the world, especially in low- and middle-income countries (LMICs). In this study using data from 51 LMICs, we found higher rates of diarrhea among children who were living through extended drought. The association was stronger among children living in a household that needed longer time to collect water or had no access to water or soap/detergent for handwashing.

Published in: Nature Communications, 2022