Suicide and apparent temperature in the two capitals cities in the iberian peninsula

Abstract

Different authors have identified geographic variations in the rates of suicide. This study aims to discuss the limitations of the officially recorded suicide data and to evaluate the statistical relationship between a biometeorological index, Apparent Temperature (AT), and suicide in Madrid and Lisbon. We performed a time-series study. The association was analyzed using a quasi-Poisson regression model. To assess potential delayed and non-linear effects of AT on suicides, a lag non-linear model was fitted in a generalized additive model. There was an average rate of 3.30 suicides/100,000 inhabitants in Madrid and of 7.92 suicides/100,000 inhabitants in Lisbon, and a downward trend was found throughout the period. In Madrid, there is no statistically significant association between AT and suicide. However, in Lisbon, under higher AT, there was a higher risk of suicide. The highest accumulated statistically significant Relative Risk (RR) of suicide was detected at 7 days after the exposure, when at 38 °C, the risk of suicide is 2.7 times that existing at the median AT, 20.62°. The average mortality rate recorded in Lisbon was 41.6% higher than that registered in Madrid. However, the limitations of suicide record databases in Spain and Portugal have to be taken into account when analyzing incidence and especially when comparing data from different countries. It isnecessary to improve the filing systems of violent deaths in order to perform reliable epidemiological studies.