Mental and substance use disorders (especially depressive disorders and anxiety) account for a considerable share of the burden of disease: 30% of years lived with disability. Environmental determinants of mental illnesses are yet to be adequately understood, however, it is essential to identify modifiable risk factors to put policies in place to reduce the incidence of these disorders. Recent epidemiological research suggests a likely link between air pollution (particularly Traffic-Related Air Pollutants, TRAPs) and psychological health. However, further studies are required to unravel inconsistencies and to fulfil the large numbers of gaps of knowledge identified by previous studies.
Prevalence of depression is greater among women, being around 20% for both anxio and depressive disorders. In the case of pregnant women, besides mother’s own well-being, anxiety or depression during pregnancy may result in abnormal cognitive and brain development of the offspring generation. Moreover, during its in-utero development, the brain is very sensitive to environmental factors through the mother, which could determine whether children would be able to reach their full neurodevelopmental potential at adulthood.
Traditionally in epidemiological studies in the field, subjects’ exposure has been based on ambient air pollutants concentrations estimated using geographical modelling at the residential address. However, this is a notable simplification: people usually spend their time in different microenvironments, and pollutant concentrations vary considerably between microenvironments (e.g. workplace and commuting). Moreover, the quantification of the inhaled dose, the total quantity of pollutant inhaled, is the product of pollutant concentration and a dosimetry factor (such as the minute ventilation, the total volume of air breathed in a minute), which is dependent on physical activity levels. Therefore, data on air pollutant concentrations, time-activity diaries and physical activity intensity is needed to determine the inhaled doses. Finally, noise has also been associated with depressive symptoms and, therefore, there is a need to evaluate the contribution of both exposures (air pollution and noise) to mental health.
Hence, the overall aim of the “Air pollution, antenatal dePRESSion and anxiety, and foetUs bRain dEvelopment” (PRESSURE) project is to assess the effect of air pollution and noise in mother’s antenatal depression and anxiety and to evaluate how mother’s depression and/or anxiety mediates the association between air pollution and the development of brain structures in the foetus. Specifically, the main research objectives are:
• To quantify the exposure and dose of pregnant women in the BiSC cohort (N=1080,
https://projectebisc.org/es/inicio/(opens in new window)) to PM2.5 Black Carbon (BC), and NO2 in different time-windows of the pregnancy period.
• To assess the effect of the exposure and dose of urban air pollution during pregnancy on antenatal depression and anxiety in BiSC.
• To evaluate the mediating role of antenatal depression and anxiety in the possible association between prenatal exposure to TRAPs and changes in structures of the growing brain in the foetuses and new-borns.
The results obtained from this work will (i) contribute with a methodology to accurately quantify the exposure and dose, (ii) add insight on the effects of TRAPs on mental health, (iii) will explore the mediation of antenatal depression and anxiety in the association between prenatal air pollution exposure and brain development.
