Si-Hyuck Kang1, Il-Young Oh1, Jongbae Heo2, Hyewon Lee3, Jungeun Kim4, Woo-Hyun Lim5, Youngjin Cho1, Eue-Keun Choi6, Seung-Muk Yi2, Do Shin Sang7, Ho Kim3, Tae-Jin Youn1, In-Ho Chae1, Seil Oh8. 1. Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea. 2. Department of Environmental Health and Institute of Health and Environment, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea. 3. Department of Biostatistics and Epidemiology, Graduate School of Public Health & Asian Institute of Energy, Environment, and Sustainability, Seoul National University, Republic of Korea. 4. Laboratory of Emergency Medical Services, Biomedical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea. 5. Department of Internal Medicine, Seoul National University College of Medicine, Boramae Medical Center, Seoul, Republic of Korea. 6. Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea. 7. Department of Emergency Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea. 8. Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea. Electronic address: seil@snu.ac.kr.
Abstract
OBJECTIVE: Cardiac arrest is one of the common presentations of cardiovascular disorders and a leading cause of death. There are limited data on the relationship between out-of-hospital cardiac arrest (OHCA) and ambient temperatures, specifically extreme heat. This study investigated how heat and heat waves affect the occurrence of OHCA. METHODS: Seven major cities in Korea with more than 1 million residents were included in this study. A heat wave was defined as a daily mean temperature above the 98th percentile of the yearly distribution for at least two consecutive days. RESULTS: A total of 50,318 OHCAs of presumed cardiac origin were identified from the nationwide emergency medical service database between 2006 and 2013. Ambient temperature and OHCA had a J-shaped relationship with a trough at 28°C. Heat waves were shown to be associated with a 14-% increase in the risk of OHCA. Adverse effects were apparent from the beginning of each heat wave period and slightly increased during its continuation. Excess OHCA events during heat waves occurred between 3PM and 5PM. Subgroup analysis showed that those 65years or older were significantly more susceptible to heat waves. CONCLUSIONS: Ambient temperature and OHCA had a J-shaped relationship. The risk of OHCA was significantly increased with heat waves. Excess OHCA events primarily occurred during the afternoon when the temperature was high. We found that the elderly were more susceptible to the deleterious effects of heat waves.
OBJECTIVE:Cardiac arrest is one of the common presentations of cardiovascular disorders and a leading cause of death. There are limited data on the relationship between out-of-hospital cardiac arrest (OHCA) and ambient temperatures, specifically extreme heat. This study investigated how heat and heat waves affect the occurrence of OHCA. METHODS: Seven major cities in Korea with more than 1 million residents were included in this study. A heat wave was defined as a daily mean temperature above the 98th percentile of the yearly distribution for at least two consecutive days. RESULTS: A total of 50,318 OHCAs of presumed cardiac origin were identified from the nationwide emergency medical service database between 2006 and 2013. Ambient temperature and OHCA had a J-shaped relationship with a trough at 28°C. Heat waves were shown to be associated with a 14-% increase in the risk of OHCA. Adverse effects were apparent from the beginning of each heat wave period and slightly increased during its continuation. Excess OHCA events during heat waves occurred between 3PM and 5PM. Subgroup analysis showed that those 65years or older were significantly more susceptible to heat waves. CONCLUSIONS: Ambient temperature and OHCA had a J-shaped relationship. The risk of OHCA was significantly increased with heat waves. Excess OHCA events primarily occurred during the afternoon when the temperature was high. We found that the elderly were more susceptible to the deleterious effects of heat waves.
Authors: Pedro M Sousa; Ricardo M Trigo; Ana Russo; João L Geirinhas; Ana Rodrigues; Susana Silva; Ana Torres Journal: Int J Biometeorol Date: 2022-01-21 Impact factor: 3.738