The correlations between air pollution and depression.

Abstract

Abstract Introduction: In the 21st century there is an increased prevalence of depression in the world. So far the mechanism of developing depression has not been exactly known. Risk factors of depression occurrence are complex and nowadays it has been emphasized that air pollution can affect the intensity of depressive symptoms. Objective: The analysis of the scientific works investigating the correlations between air pollution and depression. Material and method: The material consisted of the studies published between 2007 and 2017. A systematic review of Medline database (using PubMed search engine) was conducted by typing the English phrase (air pollution) and (depression), and 154 results were obtained. Those results which concerned nicotine addiction or dementia diseases were rejected. The inclusion criterion was the number of people tested, n>500 in case of adults, and n>200 in case of children (a small number of publications). All in all, 9 research in the population of adults and 1 research in the group of children were included to the final analysis. In the discussion part of this work some research carried out on animals and related to the subject matter of own analyses were also investigated. Results: As many as 8 out of 10 analyzed research demonstrated statistically significant correlation between long-term exposure to air pollution (mainly to fine particulate matter, PM) and depression. This correlation mainly concerned intensification of depressive symptoms during long exposure to air pollution. The exposure also resulted in changes in the neuro-transfer of serotonin and as well in neurodegenerative changes in children exposed to long-term pollution with polycyclic aromatic hydrocarbons (PAH) in prenatal life. Testing on animals indicates that air pollution affects the activation of proinflammatory processes in hippocampus, what may incidentally contribute to the formation of depressive and cognitive symptoms. Conclusions: In view of the increase of depression incidence and constantly sustained air pollution in the world, there is a need for further research on the correlation between air pollution and depression, taking into account the genetic, social and psychological factors.