Research shows that there is a link between traffic pollution and women’s mental health

It’s no secret that air pollution of any kind is bad for our health. Recently, however, there has been increased attention to the link between traffic-related air pollution (TRAP) and depression. A new study not only supports previous findings on this association, but also identifies the mediating effects of menstrual cycle characteristics. Results of the research are published arrived online today Menopause.

Thanks to population growth and urbanization, nearly a quarter of the U.S. population now lives near busy roadways, exposing these individuals to dangerous TRAP, including particulate matter and nitrogen oxides. The adverse health effects, including psychiatric disorders, of such exposure are well documented.

Several studies have already examined the link between TRAP and depression, including one study that suggested women are more vulnerable to the psychiatric effects of TRAP exposure than men. Some of these studies confirmed that the closer the distance to traffic, the greater the depressive symptoms, regardless of whether the exposure was short or long term.

What the previous studies lacked, however, was examining whether these associations are independent of key variables such as sociodemographic factors and overall reproductive health. With regard to sociodemographic factors, there are clear racial, ethnic, and socioeconomic disparities in TRAP exposures. This is because minorities and poorer population groups more often live in areas with high traffic.

TRAP exposure in middle-aged women has also predicted aspects of body composition, including fat mass, proportional fat mass and lower lean mass, as well as the risk of type 2 diabetes. From a reproductive health perspective, TRAP exposures have been associated with a number of adverse effects, including earlier puberty, irregular menstrual cycles, reduced fertility and negative birth outcomes.

In this latest study, focusing on the depressive effects of TRAP exposure, regression analyzes were conducted on nearly 700 healthy women of reproductive age involved in the Ovarian Aging Study. Researchers concluded that exposure to TRAP is associated with depression in women, and that this association is independent of a host of sociodemographic and health factors, as well as characteristics of the menstrual cycle. In addition, however, it was found that the association between TRAP exposure and depression may be partially mediated by characteristics of the menstrual cycle, reflecting reproductive health status more broadly.

“This study highlights the link between traffic-related air pollution and depression in women of reproductive age. The findings also showed a significant independent effect of socioeconomic status (SES) and reproductive health factors on the risk of depression. The links between SES and depression are particularly challenging because TRAP exposure disproportionately burdens those of lower SES, potentially paving the way for a clustering of risk factors for poor mental health in vulnerable individuals,” said Dr. Stephanie Faubion, Medical Director from The Menopause Society.