THE ITALIAN PROJECT FOR THE PREVENTION OF HEAT HEALTH EFFECTS: RESULTS FROM THE MORTALITY SURVEILLANCE SYSTEM DURING SUMMER 2004

Abstract

ISEE-377 Introduction: The impact of extreme temperatures on human health has been documented throughout the literature and after the 2003 heat wave, great attention has been paid by local governments to introduce effective prevention programs. In 2004, the Italian Department for Civil Protection implemented a three-year national project for the prevention of heat-health effects during summer. The main objectives of the project are: the implementation of city-specific warning systems (HHWWS), the development of “real time” surveillance systems for monitoring the impact of heat on mortality and to evaluate the performance of warning systems, and the introduction of national and local prevention programs. Methods: We developed surveillance systems in collaboration with local Municipalities for the period June-September 2004. Every day mortality counts for the resident population dying in the city were sent by local registry offices to the national coordination centre. Each record included: date of birth and death, sex, place of death and accidental/non-accidental cause of death. Daily counts were considered complete 72 hours after the day of death was recorded. Standardised datasets were constructed for each city, inclusive of mortality by sex and age group (0–64, 65–74 and 75+). Expected daily deaths were defined as the mean daily value of the past 6 years; extreme values, that exceeded control chart limits, were excluded from the calculation. Daily excess mortality was calculated as the difference between daily expected and observed values. Results: During the first year the mortality surveillance system was activated in eight cities (Bologna, Brescia, Firenze, Genova, Milano, Palermo, Roma, Torino). The surveillance system allowed the monitoring of daily mortality and the identification of increments in mortality associated to heat waves. Previous-day mortality data was used to develop city-specific HHWWS based on autoregressive models, which predict the increase in mortality for the following 72 hours. Furthermore, mortality data was used to evaluate the effectiveness of preventive programs. The surveillance system was heterogeneous in the accuracy of mortality counts and timing of data retrieval. This was principally due to the different methodologies with which local data was collected and then sent to the national coordination centre, thus producing an underestimation in daily mortality counts. To determine the validity and completeness of mortality data from the surveillance systems a comparison with local mortality registries was performed. Conclusion: For 2005 the surveillance system will be fully automated, through a password protected webpage, which will ensure a more rapid and efficient monitoring of summer mortality. The surveillance systems will be extended to other cities included in the national project, and ad hoc surveillance systems, in a selection of hospital wards and retirement homes, will be implemented to provide a more detailed evaluation of the impact of heat on health during summer.