Abstract
Objectives: The authors examined the relationship of suicide in the elderly (65 years and older) to season and weather and compared it to that in the younger population (10–64 years).
Methods: Information on suicides and on weather was obtained for British Columbia for the period 1981 to 1991. The association of suicide with season and weather was assessed using Poisson regression.
Results: Whereas younger suicides were associated with season, showing a springsummer peak, elderly suicides were associated with actual weather. They increased with higher mean daily temperature for the current month (RR=1.16, 95% CI 1.05–1.28 for each 2.5° C change in mean temperature), and with lower mean daily temperature for the preceding three months (RR=1.12, 95% CI 1.01–1.23).
Conclusions: Elderly suicide rates appear to be affected by deviations of monthly mean temperature from values expected for that time of year. Increased support by service agencies at times of predicted high risk is suggested.
Résumé
Objectifs: les auteurs ont étudié le rapport existant entre le suicide chez les personnes âgées (65 ans et plus) d’une part et la saison ainsi que le temps d’autre part, et l’ont comparé aux mêmes données chez les plus jeunes (de 10 à 64 ans).
Méthodologie: les données sur les suicides et sur le temps ont été fournies par la Colombie-Britannique pour la période allant de 1981 à 1991. À l’aide d’une régression de Poisson, on a évalué l’association entre le suicide d’une part, et les saisons et le temps d’autre part.
Résultats: alors que les suicides chez les plus jeunes étaient correlés avec la saison, avec notamment une crête printemps-été, les suicides chez les personnes plus âgées étaient associés au temps. Le nombre de suicides augmentait parallèlement à l’augmentation de la température moyenne pour le mois en cours (RR = 1,16, 95 % IC 1,05–1,28 pour chaque changement de 2,5 º C de la température moyenne), et parallèlement à une température moyenne plus basse au cours des trois mois précédant (RR = 1,12, 95 % IC 1,01–1,23).
Conclusions: les taux de suicide chez les personnes âgées semblent être influencés par les fluctuations des températures moyennes mensuelles par rapport aux prévisions pour la même période de l’année. On conseille de renforcer les services de soutien lors de prévisions de risque élevé.
Footnotes
Supported by a grant from the British Columbia Health Research Foundation
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