A cold-health watch and warning system, application to the province of Quebec

Abstract

BACKGROUND AND AIM: Extreme cold weather has serious impacts on human life and health. However, almost no studies focused on cold warning systems to prevent those health effects. In Nordic regions, winter mortality is generally higher than the rest of the year such as in the province of Quebec in Canada. Therefore, the objective of this study is to focus on developing a cold-system and its application to the province of Quebec. METHODS: The proposed cold system is not only an adaptation of the current used system in Quebec for heat, but a number of improvements are also proposed. The improvements are mainly about the estimation of over-mortality/over-hospitalization and the lag of cold indicators. The former are calculated by using natural cubic splines, while the latter is chosen by a distributed lag non-linear model. RESULTS:The final proposed thresholds are between (-15 °C, -23 °C) and (-20 °C, -29 °C) according to the climatic region for over-mortality, and between (-13 °C, -23 °C) and (-17 °C, -30 °C) for over-hospitalization. CONCLUSIONS:The proposed thresholds and indicators have a high sensitivity and a relatively low number of false alarms, which means they have good performance in detecting health episodes caused by extreme cold. KEYWORDS: threshold, cold spell, mortality, hospitalization, alert, preparedness.