Kristin K Clemens1,2,3, Alexandra M Ouédraogo4, Britney Le4, James Voogt5, Melissa MacDonald6, Rebecca Stranberg7, Justin W Yan8, E Scott Krayenhoff9, Jason Gilliland5,10, Cheryl Forchuk11, Rafique Van Uum12, Salimah Z Shariff4. 1. Department of Medicine, Western University, London, Ontario, Canada. kristin.clemens@sjhc.london.on.ca. 2. ICES, Toronto, Ontario, Canada. kristin.clemens@sjhc.london.on.ca. 3. St. Joseph's Health Care London, 268 Grosvenor Street, London, Ontario, N6A 4V2, Canada. kristin.clemens@sjhc.london.on.ca. 4. ICES, Toronto, Ontario, Canada. 5. Department of Geography and Environment, Western University, London, Ontario, Canada. 6. Environment and Climate Change Canada, Dartmouth, Nova Scotia, Canada. 7. Consumer and Hazardous Products Safety Directorate, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada. 8. Division of Emergency Medicine, Western University, London, Ontario, Canada. 9. School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada. 10. Department of Pediatrics, Western University, London, Ontario, Canada. 11. School of Health Studies, Western University, London, Ontario, Canada. 12. Department of Science, University of Toronto, Toronto, Ontario, Canada.
Abstract
INTERVENTION: Ontario's Harmonized Heat Warning and Information System (HWIS) brings harmonized, regional heat warnings and standard heat-health messaging to provincial public health units prior to periods of extreme heat. RESEARCH QUESTION: Was implementation of the harmonized HWIS in May 2016 associated with a reduction in emergency department (ED) visits for heat-related illness in urban locations across Ontario, Canada? METHODS: We conducted a population-based interrupted time series analysis from April 30 to September 30, 2012-2018, using administrative health and outdoor temperature data. We used autoregressive integrated moving average models to examine whether ED rates changed following implementation of the harmonized HWIS, adjusted for maximum daily temperature. We also examined whether effects differed in heat-vulnerable groups (≥65 years or <18 years, those with comorbidities, those with a recent history of homelessness), and by heat warning region. RESULTS: Over the study period, heat alerts became more frequent in urban areas (6 events triggered between 2013 and 2015 and 14 events between 2016 and 2018 in Toronto, for example). The mean rate of ED visits was 47.5 per 100,000 Ontarians (range 39.7-60.1) per 2-week study interval, with peaks from June to July each year. ED rates were particularly high in those with a recent history of homelessness (mean rate 337.0 per 100,000). Although rates appeared to decline following implementation of HWIS in some subpopulations, the change was not statistically significant at a population level (rate 0.04, 95% CI: -0.03 to 0.1, p=0.278). CONCLUSION: In urban areas across Ontario, ED encounters for heat-related illness may have declined in some subpopulations following HWIS, but the change was not statistically significant. Efforts to continually improve HWIS processes are important given our changing Canadian climate.
INTERVENTION: Ontario's Harmonized Heat Warning and Information System (HWIS) brings harmonized, regional heat warnings and standard heat-health messaging to provincial public health units prior to periods of extreme heat. RESEARCH QUESTION: Was implementation of the harmonized HWIS in May 2016 associated with a reduction in emergency department (ED) visits for heat-related illness in urban locations across Ontario, Canada? METHODS: We conducted a population-based interrupted time series analysis from April 30 to September 30, 2012-2018, using administrative health and outdoor temperature data. We used autoregressive integrated moving average models to examine whether ED rates changed following implementation of the harmonized HWIS, adjusted for maximum daily temperature. We also examined whether effects differed in heat-vulnerable groups (≥65 years or <18 years, those with comorbidities, those with a recent history of homelessness), and by heat warning region. RESULTS: Over the study period, heat alerts became more frequent in urban areas (6 events triggered between 2013 and 2015 and 14 events between 2016 and 2018 in Toronto, for example). The mean rate of ED visits was 47.5 per 100,000 Ontarians (range 39.7-60.1) per 2-week study interval, with peaks from June to July each year. ED rates were particularly high in those with a recent history of homelessness (mean rate 337.0 per 100,000). Although rates appeared to decline following implementation of HWIS in some subpopulations, the change was not statistically significant at a population level (rate 0.04, 95% CI: -0.03 to 0.1, p=0.278). CONCLUSION: In urban areas across Ontario, ED encounters for heat-related illness may have declined in some subpopulations following HWIS, but the change was not statistically significant. Efforts to continually improve HWIS processes are important given our changing Canadian climate.
Authors: A Fouillet; G Rey; V Wagner; K Laaidi; P Empereur-Bissonnet; A Le Tertre; P Frayssinet; P Bessemoulin; F Laurent; P De Crouy-Chanel; E Jougla; D Hémon Journal: Int J Epidemiol Date: 2008-01-13 Impact factor: 7.196
Authors: Hong Chen; Jun Wang; Qiongsi Li; Abderrahmane Yagouti; Eric Lavigne; Richard Foty; Richard T Burnett; Paul J Villeneuve; Sabit Cakmak; Ray Copes Journal: CMAJ Open Date: 2016-02-02
Authors: Dave Henderson; Louise Aubin; Kevin Behan; Hong Chen; Helen Doyle; Stephanie Gower; Melissa MacDonald; Carol Mee; Gregory R A Richardson; Greg Rochon; Mira Shnabel; Jay Storfer; Abderrahmane Yagouti; Anna Yusa Journal: Can J Public Health Date: 2020-06-10
Authors: Kaddour Mehiriz; Pierre Gosselin; Isabelle Tardif; Marc-André Lemieux Journal: Int J Environ Res Public Health Date: 2018-07-25 Impact factor: 3.390