2026-05-06 ジョンズ・ホプキンス大学（JHU）
＜関連情報＞
- https://hub.jhu.edu/2026/05/06/asthma-rates-baltimore-heat-waves/
- https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GH001501
極端な暑さが小児および成人喘息の救急外来受診に及ぼす影響：地球観測と熱波の定義の評価 Impact of Extreme Heat on Emergency Department Admissions for Childhood and Adult Asthma: An Evaluation of Earth Observations and Heat Wave Definitions
B. Corpuz, E. Scott, B. F. Zaitchik, S. Zeger, D. Waugh, A. Balasubramanian, J. Madrigano, K. Koehler, R. Koehl, M. McCormack
GeoHealth Published: 06 May 2026
DOI:https://doi.org/10.1029/2025GH001501
Abstract
Extreme heat has been associated with adverse health outcomes, yet its impact on asthma exacerbations remains understudied. This is, in part, due to data limitations: research that relies on weather station records and aggregated health statistics cannot resolve fine-scale differences in heat impacts. This study investigates the association between heat wave definitions and summertime asthma-related emergency department visits in Baltimore, Maryland from 2016 to 2022, including 819 adult and 695 pediatric exacerbations. Using geocoded electronic health records and air temperature measurements at several spatial resolutions, we applied a case-crossover design with conditional logistic regressions at the census block group and tract levels. We found strong associations between asthma exacerbations and nighttime heat wave definitions based on relative thresholds of minimum temperatures when census block group or tract level temperature estimates were used. These relationships were significant for both age groups and showed elevated risks in socially vulnerable areas. In contrast, heat wave definitions derived from the city’s primary National Weather Service synoptic weather station show associations between asthma and daytime heat extremes, suggesting that the character of the heat hazard depends on the scale at which it is defined. The extreme heat event definition used by Baltimore City’s Code Red system showed no significant association with exacerbations. These findings highlight the importance of data resolution in shaping health inferences related to extreme heat in urban environments. Further, this study demonstrates that, regardless of spatial scale, extreme heat is associated with asthma exacerbations in both age groups.
Plain Language Summary
Extreme heat is known to impact human health, but its effects on asthma are understudied. This study investigated the relationship between heat wave definitions and asthma-related emergency department visits in Baltimore from 2016 to 2022, including 819 adult and 695 pediatric cases. By combining geocoded medical records with air temperature measurements at several spatial resolutions, we found that heat wave definitions based on elevated minimum nighttime temperatures were associated with asthma exacerbations in both age groups especially in socially vulnerable neighborhoods. These associations were observed when using high resolution temperature data, which capture neighborhood-level heat exposure. In cities like Baltimore, the urban heat island effect is more pronounced at night, resulting in sustained elevated nighttime temperatures. This highlights the importance of high-resolution temperature data in detecting localized heat exposure. In contrast, heat wave definitions from coarse resolution synoptic weather stations captured daytime heat impacts, but missed nighttime effects. Our findings emphasize the value of granular health and temperature data in identifying localized heat impacts on asthma. Baltimore’s heat alert systems rely on daytime heat indices, which may underestimate the full extent of heat exposure. Incorporating nighttime metrics into public health warnings could strengthen heat preparedness and better protect vulnerable populations.
