Air Pollution Exposure Linked To Psoriasis Flare-Ups In New Study

The findings of a new study raise further concerns about the long-term side effects of air pollution, indicating that exposure increases the likelihood of suffering from a psoriasis flare up.

In a report published this week in the medical journal JAMA Dermatology, researchers indicate that higher exposure to air pollution, such as fine particulate matter and carbon monoxide, increases the risk of psoriasis flare ups and the likelihood of having a more severe flare up.

Researchers from the University of Verona conducted a study involving nearly 1,000 individuals affected by chronic plaque psoriasis, with nearly 4,400 follow-up visits from September 2013 to January 2020. The study included patients who consecutively attended the outpatient dermatologic clinic of the University Hospital of Verona, Italy.

Patients were included if they had at least one disease flare up of severity 5 or greater, according to the Psoriasis Area and Severity Index (PASI), between two consecutive assessments within three to four months.

The researchers assessed cumulative concentrations of air pollutants, including carbon monoxide, nitrogen dioxide, other nitrogen oxides, benzene, coarse particulate matter, and fine particulate matter 2.5 (PM 2.5) and particulate matter 10 (PM 10), in the 60 days before a psoriasis flare up, as well as for the control visits. Researchers conducted more than 15,000 measurements of air pollutant concentrations.

According to the findings, psoriasis flare ups were more common when concentrations of air pollutants were significantly higher in the 60-day period before the flare up occurred. Researchers also defined the definition of psoriasis flare up using the PASI identification. Roughly 36% of patients had at least a 50% increase in PASI flare definition and 47% had a 100% increase in PASI compared to the control visit.

The researchers found that exposure to PM 10 over μg/m3 and PM 2.5 over 15 μg/m3 in the 60 days before a flare up were linked with a higher risk of having a PASI 5 or greater score flare.

Psoriasis is a chronic, inflammatory disease which leads to a scaly, red, itchy rash on various parts of the body. It is a relapsing-remitting condition with no permanent cure or treatment. Things that can lead to a psoriasis flare include infections, stressful life events, or even medications and street drugs. Flares lead to red, inflamed, scaly patches on the skin that are not only itchy, but extremely uncomfortable.

The findings of the new study highlight the role air pollution may play in exacerbating the condition. The researcher speculate that after inhalation, air pollutants can circulate in the bloodstream leading to oxidative damage and causing inflammation in the body, which may prompt a psoriasis flare up.

Researchers caution that more studies are needed to determine if these findings are generalized.