Environment/Climate Change
Grouped mixtures of air pollutants and seasonal temperature anomalies and cardiovascular hospitalizations among US residents Yaguang Wei* Yaguang Wei Heresh Amini Tingfan Jin James Healy Brent Coull
Background: Air pollution is a recognized risk factor for cardiovascular disease (CVD). Temperature is also linked to CVD, with a primary focus on acute effects. Despite the close relationship between air pollution and temperature, their effects are often examined separately, potentially overlooking their synergistic effects.
Methods: We obtained hospitalization records for residents of 14 US states between 2000–2016 from the Health Cost and Utilization Project. We used a grouped weighted quantile sum regression, a novel approach for mixture analysis, to simultaneously evaluate cumulative and individual associations of annual exposures to four grouped mixtures: air pollutants (elemental carbon, ammonium, nitrate, organic carbon, sulfate, nitrogen dioxide, ozone), deviations of summer and winter temperature means from the long-term averages (i.e., seasonal temperature mean anomalies), deviations of summer and winter temperature standard deviations from the long-term averages (i.e., seasonal temperature variability anomalies), and interactions between air pollutants and seasonal temperature mean anomalies. Outcomes are hospitalization rates for four prevalent CVD subtypes: ischemic heart disease, cerebrovascular disease, heart failure, and arrhythmia.
Results: Chronic exposure to air pollutant mixtures was associated with increased hospitalization rates for all CVD subtypes, with heart failure being the most susceptible subtype and sulfate, nitrate, nitrogen dioxide, and organic carbon being the most toxic pollutants. Mixtures of interactions between air pollutants and seasonal temperature mean anomalies were associated with increased hospitalization rates for all CVD subtypes.
Conclusions: The most toxic pollutants identified would inform source-specific emission control policies. Hotter summers and colder winters jointly exacerbated adverse effects of chronic exposure to air pollution on cardiovascular health.
