DAILY MORTALITY IN MADRID COMMUNITY 1986-1992 - RELATIONSHIP WITH METEOROLOGICAL VARIABLES

Daily mortality displays a seasonal pattern linked to weather, air pol lution, photoperiod length, influenza incidence and diet, among which temperature ranks as a leading cause. This study thus sought to assess the relationship between temperature, relative humidity, wind speed a nd mortality in the Madrid Autonomous Region (Spain) for the period Ja nuary 1986-December 1992, controlling for the effects of air pollution and influenza incidence. Daily data on maximum, minimum and 24-hour m ean temperature, relative humidity and wind speed were matched against daily mortality. Transfer function was identified using the Box-Jenki ns pre-whitening method. Multivariate time series regression models we re used to control for the confounding effects of air pollution and in fluenza incidence. Separate seasonal analyses were carried our for win ter and summer periods. A J-shaped relationship between outdoor temper ature, relative humidity and daily mortality was found. Mortality prov ed to be inversely related to cold temperature (4- to 11-day lag) and directly related to warm temperature (1-day lag). High relative humidi ty during summer periods was negatively related to mortality. Thermal variation ascribable to Madrid's mesothermal Mediterranean climate was strongly related to daily mortality, even where air pollution and inf luenza incidence were controlled for.