Individual effects and interactions between ultrafine particles and extreme temperatures on hospital admissions of high burden diseases

Quan Qi3, Najm Alsadat Madani2, Yukang Xue3, Randy T. Tangang1, *, Xiaobo Romeiko Xue4, Shao Lin4, Fangqun Yu1, Arshad Nair1, Gan Luo1, Chris Thorncroft1, and Isa Brackett2

Background: Research on the health effects of ultrafine particles (UFPs) is limited, especially considering its individual and interaction with extreme temperatures. This study investigates the risks of UFPs number concentrations and extreme temperatures on hospitalizations for high-burden diseases (HBDs) in New York State (NYS).

Methods: We defined HBDs including ischemic heart diseases, diabetes, stroke, kidney diseases, and depression from NYS Hospital Discharge Data, 2013-2018. Daily temperature and pollutants were obtained from chemical transport model with aerosol microphysical simulation with 17x17 miles resolution. UFPs were measured using interquartile range (IQR) increase; extreme heat was defined as temperature >= 90th percentile in summer; and extreme cold as temperature <=10th percentile in winter. Conditional logistic regression with a case-crossover study design were applied while controlling for criteria pollutants, relative humidity, and time-varying variables.

Results: Among 1,308,518 cases in NYS, significant risk ratios (RR) were observed for UFPs (RRIQR: 1.009 to 1.012) and extreme cold (RR: 1.009 to 1.053), but no effect was found for extreme heat. UFPs affected all HBD subtypes except kidney diseases, with the highest RR for diabetes (1.026, 95% CI: 1.011, 1.041). Extreme cold impacted all subtypes, with the highest RR for depression (1.063, 95% CI: 1.035, 1.092). Females, Blacks, non-Hispanics, older adults and those with Medicare or Medicaid were more susceptible to UFPs, while whites, non-Hispanics, older adults, and Medicare recipients were more vulnerable to extreme cold. The adverse effect of UFPs was higher in winter and fall. Elevated UFP concentrations and extreme cold temperatures were associated with longer hospital stays and higher total charges.

Conclusion: We observe short-term associations between exposure to elevated UFPs concentrations or extreme cold and hospitalizations, length of stay, and total charges for HBDs in NYS. These effects varied by sociodemographic groups and seasons, with UFPs having stronger impacts during winter and extreme cold.

1 Atmosphere Science Research Center, University at Albany, State University of New York, Albany, NY

2 New York State Department of Health, Albany, NY

3 Department of Economics, University at Albany, State University of New York, Albany, NY

4 Institute for Health and the Environment, University at Albany, State University of New York, Rensselaer, NY

5 Department of Epidemiology and Biostatistics, School of Public Health, University at Albany, State University of New York, Rensselaer, NY

* Corresponding Author: rtangang@albany.edu