Air pollution, a possible risk factor for multiple sclerosis

Objective Studies focusing attention on the effects of environmental pollution on the etiology of multiple sclerosis (MS) are on the increase. The aim of this study was to determine MS prevalence in a city home to an iron and steel factory which causes air pollution. Methods The study was designed as a cross-sectional, population-based, descriptive epidemiologic study. Eregli city, which has an iron and steel factory and proven air pollution, was screened. Additionally, Devrek city, which is a rural and clean city, located 40 km away from Eregli was assigned and results were compared. A validated questionnaire was used for screening. McDonald 2010 criteria were used to diagnose cases. Results 32 261 people were screened in Eregli, and 21 963 people were screened in Devrek. In total, 41 patients were diagnosed with clinical definite MS. Crude prevalence was found to be 96.1/100 000 in Eregli and 45.5/100 000 in Devrek. The mean age of patients was 39.8, and the female/male ratio was 1.9. Conclusion The results of this study indicate a more than double MS prevalence rate in the area home to an iron and steel factory when compared to the rural city. This supports the hypothesis that air pollution may be a possible etiological factor in MS.