Association Between Suicide and Environmental Variables in the North of Spain: A 14-Year Analysis

Suicide is a serious public health problem around the world. Since the nineteenth century, the impact of socio-environmental factors on suicide has attracted much public attention, especially in the context of global climate change. We have performed a retrospective correlation study that analyzes the demographic pattern of suicide in Cantabria, a northern coastland region of Spain. Moreover, we have created a multivariable binomial regression model to study the relationship between suicide and environmental factors (atmospheric pollutants and meteorological variables) among January 1, 2000, and December 31, 2013 in the province. During the 14-year study period, there was a suicide annual incidence of 4.9 cases per 100,000 population in Cantabria. The incidence was highest in adults aged 70-74 years old (11.8 per 100,000 population). The most common method group of suicide was hanging, strangulation and suffocation, accounting for 49.3% of all suicide deaths. When correlating suicide and meteorological variables, a statistically significant association was found with the level of cloudiness (p = 0.007). According to our results, an increase of one eighth of sky cloud-cover correlated to a 7% increase in total deaths by suicide and the association was especially strong during spring.