The Impact of PM2.5 Air Pollution on the Annual Incidence of Multiple Sclerosis in Isfahan, Iran: A Retrospective Cohort Study (PP-28)

Introduction: Multiple sclerosis (MS) is a chronic neurodegenerative disorder that results from autoimmune inflammation of the central nervous system. Environmental factors, particularly air pollution, have emerged as potential contributors to MS pathogenesis. This study investigates the relationship between PM2.5 levels and the annual incidence of MS in Isfahan, Iran, a city noted for high pollution and MS prevalence.
Objectives: The primary aim is to evaluate the association between daily PM2.5 concentrations and the incidence of MS in various urban areas of Isfahan over a decade, from 2011 to 2021.
Methods: This retrospective cohort study utilized data from the Iranian Statistical Center, the Medical University of Isfahan, and local air pollution monitoring centers. A total of 4,984 patients diagnosed with MS were analyzed, and their annual incidence rates were calculated based on urban regions. PM2.5 levels were monitored across seven air pollution centers. Statistical analyses included Poisson regression models, comparing MS incidence rates with PM2.5 exposure while adjusting for potential confounders.
Results: The findings indicate an average annual MS incidence of 1.70 per 10,000 people, with a significant relationship between PM2.5 levels and MS incidence. Specifically, increased PM2.5 concentrations correlated with higher MS rates, particularly in the Northwest region of the city. Elevated PM2.5 levels were also associated with worsening disability scores (EDSS) in affected patients.
Conclusion: This study highlights the potential impact of air pollution on MS incidence, suggesting that high PM2.5 levels may exacerbate disease outcomes in vulnerable populations. Further research is warranted to clarify these associations and inform public health interventions.