Health impacts of the July 2010 heat wave in Québec, Canada

Abstract

BackgroundOne of the consequences of climate change is the increased frequency and intensity of heat waves which can cause serious health impacts. In Québec, July 2010 was marked by an unprecedented heat wave in recent history. The purpose of this study is to estimate certain health impacts of this heat wave.MethodsThe crude daily death and emergency department admission rates during the heat wave were analyzed in relation to comparison periods using 95% confidence intervals.ResultsDuring the heat wave, the crude daily rates showed a significant increase of 33% for deaths and 4% for emergency department admissions in relation to comparison periods. No displacement of mortality was observed over a 60-day horizon.ConclusionsThe all-cause death indicator seems to be sufficiently sensitive and specific for surveillance of exceedences of critical temperature thresholds, which makes it useful for a heat health-watch system. Many public health actions combined with the increased use of air conditioning in recent decades have contributed to a marked reduction in mortality during heat waves. However, an important residual risk remains, which needs to be more vigorously addressed by public health authorities in light of the expected increase in the frequency and severity of heat waves and the aging of the population.

The Distribution of Climate Change Public Opinion in Canada

“…Sea ice loss, thawing permafrost, and coastal erosion are already accelerating [7][8][9], and impacts from extreme weather such as droughts, flooding, and heat waves [10][11][12], as well as ecological disturbances such as wildfires and pine beetle outbreaks are projected to increase [13,14]. All of these factors make climate action in Canada both vital and difficult.…”

Risk and protective factors for heat-related events among older adults of Southern Quebec (Canada): The NuAge study

“…[3][4][5]7 However, these provincial rates varied greatly from one year to another and were measured only in health regions that experienced heat waves, which may imply higher burden than single HTD. Defined as maximal/minimal temperature of ≥31°C/≥18°C (threshold for Eastern Townships) and ≥33°C/≥20°C (threshold for Montréal/ Laval) for at least three days, 7 only one heat wave occurred in Montreal/Laval and two in the Eastern Townships during the five summers investigated.…”

Heat-related deaths

“…Certainly, forensic pathologists are continually encountering cases where deaths may have either been caused by, or associated with, high environmental temperatures, and in many parts of the world there does appear to have been an increase in numbers of heat-related deaths [3,4]. In January-February 2009, summer temperatures in Adelaide, the capital of South Australia, reached record levels, with 8 days having maximum temperatures above 40°C, including the hottest day in 70 years with a temperature of 45.7°C [5].…”

“…For this reason a mathematical formulation termed the Excess Heat Factor has recently been derived based on long-term local metereological data to allow a more accurate indication of the severity of a heat event to be determined, rather than merely relying on sequentially recording maximum daily temperatures [3]. This calculation can provide a way of scoring environmental temperature load and thus enable prediction of the likelihood of a significant increase in the number of heat related deaths.…”

“…This calculation can provide a way of scoring environmental temperature load and thus enable prediction of the likelihood of a significant increase in the number of heat related deaths. It can also be used in clinical practice to predict increases in heat related morbidity [3]. The two major components of successfully dealing with major clusters of deaths arising from heat waves remain forewarning and disaster victim management preparedness [20].…”