Excess mortality in people over 65 years old during summer heat waves in Marseille -: Comparison before and after a preventive campaign

Introduction High temperatures induce excess mortality in the population, even in our country. The 1983 heat wave in Marseille led to the development of warning messages in a preventive campaign since 1984. Objective To compare mortality of people over 65 years old during summer heat waves before and after a campaign in Marseille. Method The INSEE mortality data were analysed according to the mean temperatures supplied by the National Meteorological Office from 1968 to 1997. A mortality index was developed to limit the effect of the progression in mortality over the last 30 years. The heat wave was defined as a temperature greater than or equal to26 degreesC lasting for 2 days during the months of June to August. Results The mean summer temperature in Marseille has increased from 22 to 23 degreesC in 30 years. The number of days of heat wave has also increased during this period. The mean index of daily excess mortality has dropped from 3.27 (1968-1982) to 1.32 (1984-1997) (p = 0.008). Conclusion The effects of global warming have been noted in Marseilles over the last 30 years. there has been no disappearance in excess mortality, but the warning messages appear to have been partially effective, even if other factors may have intervened (airconditioning...).This prevention, like that for the risks related to air pollution, should be generalized because it is inexpensive, although assessment of its efficacy is difficult. (C) 2004, Masson, Paris.