Aitana Lertxundi
Without being able to view the supplementary material or read the methodology, it could be said that the authors have followed the protocol correctly to produce a high-quality systematic review.
This is a very important area of research, as it accounts for 1 per cent of mortality in Europe – that is, 10 deaths per 100,000 inhabitants – and in Spain, eight deaths per 100,000 inhabitants. Therefore, investigating which factors are linked to suicide-related mortality is essential for defining strategic prevention measures. There is already sufficient scientific evidence to suggest that air pollution, as an environmental factor, is linked to premature mortality and hospital admissions due to respiratory, cardiovascular and cerebrovascular problems, but there is growing evidence that it also affects mental health. In fact, this year we have published an article on mental health and air pollution in which we clearly see a link with anxiety and depression. The European Environment Agency has published results very similar to those in our article on its website, and they also discuss suicide.
The main limitation of this review is the small number of available studies and the high degree of heterogeneity amongst them (type of epidemiological study, type of study population, method of measuring the association, exposure-outcome relationship, etc.), which makes it difficult to obtain consistent results.
Given the results we have obtained and what we are finding in the scientific evidence regarding suicide and air pollution, it is clear that, in suicide prevention, environmental factors must be incorporated into public health policies, with particular attention paid to environmental and social inequalities.