title: Heat-Related Hospitalizations in Older Adults: An Amplified Effect of the First Seasonal Heatwave.
abstract: Older adults are highly vulnerable to the detriment of extreme weather. The rapid non-linear increase in heat-related morbidity is difficult to quantify, hindering the attribution of direct effects of exposure on severe health outcomes. We examine the effects of ambient temperatures on heat-related hospitalizations (HH) among the elderly in presence of strong seasonality and by assessing the effects caused by the first and subsequent seasonal heatwaves. We empirically derived the thresholds for a heatwave episode in Boston MSA based on 16 years of daily observations. We compared the health risks of heatwaves using the proposed and four alternative definitions. 701 cases of HH in older residents of Boston area were examined using harmonic regression models, designed to capture the non-linear effects of ambient temperatures and heatwave episodes when the night-time temperature is above 65.5 °F for 3 consecutive nights. The overall relative risk of HH associated with a heatwave episode was 6.9 [95%CI:4.8-9.8]. The relative risk of HH associated with the first heatwave increases up to 13.3 [95%CI:7.4-24.0]. The risk declined to 3.7 [95%CI:2.4-5.8] for the subsequent heatwave. Four other commonly used heatwave definitions confirmed these findings. Public health actions have to target the first heatwave to maximize the impact of preventive measures.
authors.affiliation: Department of Civil and Environmental Engineering, Tufts University School of Engineering, Medford, MA 02155, USA.|Initiative for the Forecasting and Modeling of Infectious Diseases, Tufts University, Medford, MA 02155, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Liss
authors.affiliation: Department of Civil and Environmental Engineering, Tufts University School of Engineering, Medford, MA 02155, USA.|Initiative for the Forecasting and Modeling of Infectious Diseases, Tufts University, Medford, MA 02155, USA.
authors.forename: Ruiruo
authors.initials: R
authors.lastname: Wu
authors.affiliation: Initiative for the Forecasting and Modeling of Infectious Diseases, Tufts University, Medford, MA 02155, USA.|Department of Public Health and Community Medicine, Tufts University School of Medicine, Boston, MA 02111, USA.
authors.forename: Kenneth Kwan Ho
authors.initials: KK
authors.lastname: Chui
authors.affiliation: Department of Civil and Environmental Engineering, Tufts University School of Engineering, Medford, MA 02155, USA.|Initiative for the Forecasting and Modeling of Infectious Diseases, Tufts University, Medford, MA 02155, USA.|Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA 02111, USA.
authors.forename: Elena N
authors.initials: EN
authors.lastname: Naumova
mesh_terms: D000368:Aged; D001900:Boston; D006760:Hospitalization / Q000706:statistics & numerical data*; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D007259:Infrared Rays / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D012621:Seasons