Effects of extremely hot days on people older than 65 years in Seville (Spain) from 1986 to 1997

Abstract

The effects of heat waves on the population have been described by different authors and a consistent relationship between mortality and temperature has been found, especially in elderly subjects. The present paper studies this effect in Seville, a city in the south of Spain, known for its climate of mild winters and hot summers, when the temperature frequently exceeds 40 degrees C. This study focuses on the summer months (June to September) for the years from 1986 to 1997. The relationships between total daily mortality and different specific causes for persons older than 65 and 75 years, of each gender, were analysed. Maximum daily temperature and relative humidity at 7.00 a.m. were introduced as environmental variables. The possible confounding effect of different atmospheric pollutants, particularly ozone, were considered. The methodology employed was time series analysis using Box-Jenkins models with exogenous variables. On the basis of dispersion diagrams, we defined extremely hot days as those when the maximum daily temperature surpassed 41 degrees C. The ARIMA model clearly shows the relationship between temperature and mortality. Mortality for all causes increased up to 51% above the average in the group over 75 years for each degree Celsius beyond 41 degrees C. The effect is more noticeable for cardiovascular than for respiratory diseases, and more in women than in men. Among the atmospheric pollutants, a relation was found between mortality and concentrations of ozone, especially for men older than 75.

Decreased impacts of the 2003 heat waves on mortality in the Czech Republic: an improved response?

“…The fact that the excess mortality due to heat is more pronounced in females than males is in accord with western European countries during the 2003 heat waves (e.g., Pirard et al 2005;Michelozzi et al 2005;Borrell et al 2006) as well as other previous events (Rooney et al 1998;Díaz et al 2002aDíaz et al , 2002b. It is likely related to a demographic and social structure of the European population, particularly a larger percentage of females among the elderly and among those living alone (INSTRAW 2004).…”

“…Since the relationship between summer heat and mortality is often found to be stronger with the lag of 1 day compared to unlagged relationships (Auliciems et al 1997, Díaz et al 2002a, Ramlow and Kuller 1990, Sartor et al 1995, Whitman et al 1997, Davis et al 2003, Grize et al 2005, Kosatsky 2005), both the 0-day and 1-day lags between mortality and HI were examined.…”

“…The most direct effects of weather on human mortality in mid-latitudes are observed during and after summer heat waves that lead to significant increases and intraseasonal shifts ('displacements') in total mortality (e.g., Kunst et al 1993;Hajat et al 2002;Huynen et al 2001;Smoyer et al 2000b;Laschewski and Jendritzky 2002;Díaz et al 2002a;Kyselý 2004;Kosatsky 2005;Gosling et al 2007). Heat has been recognized as the most deadly factor among all atmospheric hazards (e.g., Klineberg 1999;Sheridan and Kalkstein 2004), and at least in the mid-latitudes, heatrelated mortality also represents the main source of negative impacts of the likely future global warming on human health (Keatinge and Donaldson 2004;Poumadere et al 2005;Haines et al 2006).…”

A Large Change in Temperature between Neighbouring Days Increases the Risk of Mortality

“…There is evidence that women are more vulnerable to heat-related mortality than men [22], [23], [24], [25]. Studies have also found that women have higher risks for ischemic, arrhythmic and blood pressure effects associated with the weather [26], [27]. However, Basu [28] pointed out that the differences of the effect of temperature on women and men was dependent on location and population.…”

Effects of high summer temperatures on mortality in 50 Spanish cities

“…Maximum temperature was chosen as the index providing best fit in previous single city-studies conducted in Spain cities [13-15]. A lagged effect for up to two days, after that heat effects declined has also been shown [12].…”