Abstracts: ISEE 22nd Annual Conference, Seoul, Korea, 28 August–1 September 2010: Climate Change and Environmental Health
Climate change predictions estimate an increase in temperatures and extreme events especially in the Mediterranean area. The impact of high temperatures on mortality in European cities are well known, while the effect in urban areas of North Africa and the Middle East are to date limited. This study, carried out within the CIRCE EU Project, aims to assess the impact of extreme temperatures on mortality in 10 Mediterranean cities (Athens, Bari, Barcelona, Istanbul, Lisbon, Palermo, Rome, Telaviv, Tunis, and Valencia). The analysis allows the comparison of the effect among the more temperate European and drier North African and Middle Eastern areas of the Mediterranean.
Maximum apparent temperature (Tappmax) was chosen as exposure variable to estimate the impact on total mortality (by age groups) during summer. The segmented regression approach was used to identify city-specific threshold values of Tappmax, corresponding to the minimum mortality rate. A time-series approach was used to estimate the percent increase in mortality for 1°C increase in Tappmax above the city-specific threshold.
Great heterogeneity among cities was observed in the exposure and in the threshold values, ranging from 25°C in Lisbon to 36°C in Tunis. The Tappmax-mortality relationship showed a J-shaped curve in most cities, with a significant impact of high temperatures on mortality above the threshold, but in the hottest cities as Telaviv, Tunis and Valencia the relationship was weaker. In most cities, the greatest impact of high temperatures on mortality was found in the 65+ age group, ranging from +1.71% in Telaviv to +6.15% in Rome; while in the 0–64 age group the impact was higher in Lisbon (+9.21%) and Telaviv (+3.60%).
The impact of high temperatures on mortality was heterogeneous among the Mediterranean cities, although the greatest impact on mortality wasn't in the hottest cities, suggesting local population adaptation to heat.