Prolonged exposure to air pollution associated with higher risk of psoriasis: JAMA

A recent study published in the Journal of the American Medical Association found there may be a link between a higher risk of psoriasis and prolonged exposure to air pollution.

One autoinflammatory disease that is frequently impacted by intricate interplay between hereditary and environmental variables is psoriasis. Thus, Junhui Wu and colleagues carried out this research to investigate the relationship between chronic air pollution exposure and psoriasis, as well as the interplay between air pollution and genetic predisposition to incident psoriasis.

Data from the UK Biobank were utilized in this prospective cohort study where the analytic sample comprised of individuals who reported exposure to air pollution but had no history of psoriasis at baseline. Only white people were included in the genetic analysis with the risk factors for psoriasis ranging from exposure to fine particulate matter (PM2.5), PM10, NO2, and NOx to inherited susceptibility. A Cox proportional hazards model was employed with time-varying exposure to air pollution to investigate the association of long-term exposure to NOx, NO2, PM2.5, and PM10 and the likelihood of psoriasis. 

A total of 4,74,055 participants in all were included in the study where 2,57,686 (54.36%) were female participants with a mean (SD) age of 56.54 (8.09) years. The exposure to air pollutants was positively correlated with the risk of psoriasis.

The hazard ratios (HRs) were 1.41, 1.47, 1.28, and 1.19 for each IQR increase in PM2.5, PM10, NO2, and NOx, respectively. The multivariate-adjusted HRs for PM2.5, PM10, NO2, and NOx were 2.01, 2.21, 1.64, and 1.34 when compared to the individuals in the lowest exposure quartile (Q1) with those in the highest exposure quartile (Q4).

Furthermore, strong correlations were found between genetic susceptibility to incident psoriasis and air pollution. The results found that among the 4,46 637 White participants in the subset, the individuals who were exposed to the highest quartile of air pollution levels concurrent with high genetic risk had a significantly higher risk of developing psoriasis.

Overall, this study employed the prospective data to investigate this link between different air contaminants and the development of psoriasis. The findings of this comprehensive research demonstrated a rise in psoriasis risk among the people with higher genetic predisposition and more exposure to air pollution.

Reference:

Wu, J., Ma, Y., Yang, J., & Tian, Y. (2024). Exposure to Air Pollution, Genetic Susceptibility, and Psoriasis Risk in the UK. In JAMA Network Open (Vol. 7, Issue 7, p. e2421665). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2024.21665