Environmental factors drive inflammatory responses
Peter L. Loper Jr., MD, considers the findings of the Developmental Psychology study to be unsurprising but important – because air pollution is simply getting worse.
Dr. Peter L. Loper
“As the study authors cite, there is sufficient data correlating ozone to negative physical health outcomes in youth, but a paucity of data exploring the impact of poor air quality on mental health outcomes in this demographic,” noted Dr. Loper, of the University of South Carolina, Columbia, in an interview.
“As discussed by the study researchers, any environmental exposure that increases immune-mediated inflammation can result in negative health outcomes. In fact, there is already data to suggest that similar cytokines, or immune cell signalers, that get released by our immune system due to environmental exposures and that contribute to asthma, may also be implicated in depression and other mental health problems,” he noted.
“Just like downstream symptom indicators of physical illnesses such as asthma are secondary to immune-mediated pulmonary inflammation, downstream symptom indicators of mental illness, such as depression, are secondary to immune-mediated neuroinflammation,” Dr. Loper emphasized. “The most well-characterized upstream phenomenon perpetuating the downstream symptom indicators of depression involve neuroinflammatory states due to psychosocial and relational factors such as chronic stress, poor relationships, or substance use. However, any environmental factor that triggers an immune response and inflammation can promote neuroinflammation that manifests as symptoms of mental illness.”
The message for teens with depression and their families is that “we are a product of our environment,” Dr. Loper said. “When our environments are proinflammatory, or cause our immune system to become overactive, then we will develop illness; however, the most potent mediator of inflammation in the brain, and the downstream symptoms of depression, is our relationships with those we love most,” he said.
Dr. Loper suggested research aimed at identifying other sources of immune-mediated inflammation caused by physical environments and better understanding how environmental phenomenon like ozone may compound previously established risk factors for mental illness could be useful.
The RMD Open study received no outside funding, and its authors had no financial conflicts.
The Developmental Psychology study was supported by the National Institute of Mental Health and the Stanford University Precision Health and Integrated Diagnostics Center. The researchers for that report, and Dr. Loper and Dr. Barrett had no conflicts to disclose.