Investigating the Relationship between Seasonal Fluctuations and the Number of Relapsing-Remitting Multiple Sclerosis Attacks in Qom

Background: Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS). Environmental factors such as seasonal changes and air pollution play a significant role in the progression and relapse of this disease. This study aimed to investigate the impact of seasonal changes and air pollution on the frequency and severity of MS attacks in patients from Qom province. Methods: This cross-sectional analytical study included 491 patients with relapsing-remitting MS (RRMS) registered with the MS Association of Qom province from 2016 to 2021. Data on temperature, humidity, and air pollutants (PM2.5, PM10, and O3) were collected from the Meteorological Organization and the Environmental Protection Agency of Qom province. Missing data were estimated using the Multiple Imputation method. Data were analyzed using the Generalized Additive Model (GAM) and R software. Results: The mean number of relapses was 0.68±5.21. The results showed that increased temperature was directly correlated with a higher number of relapses (r=0.46, P<0.001), while increased relative humidity was associated with a decrease in relapses (r=-0.35, P=0.006). Additionally, PM10 and PM2.5 pollutants were directly related to an increase in relapses. Comorbid autoimmune diseases and family history of MS were also significantly associated with the number of relapses (P=0.000). Conclusion: This study emphasizes the complexity of relationships between environmental factors, demographic characteristics, and the onset of MS relapses, underscoring the need for integrated strategies in managing MS patients.