Annual average of PM2.5 in Isfahan city.

BackgroundMultiple sclerosis (MS) is a neurodegenerative disorder of the central nervous system characterized by autoimmune inflammation. Recent research indicates that environmental factors, particularly air pollution, may significantly affect the risk of developing MS.ObjectiveThis study investigates the association between PM2.5 levels, as a measure of air pollution, and the incidence of MS in Isfahan, Iran, a city with one of the highest reported MS prevalence rates in the country.MethodsA retrospective population-based cohort study was conducted using data from the National MS registry of Iran and Isfahan’s air pollution monitoring department from 2011 to 2021. The incidence of MS across urban areas was calculated, and the relationship between PM2.5 levels and the incidence rate ratio (IRR) of MS was assessed using a Poisson generalized regression models.ResultsPM2.5 levels averaged 41.99 µg/m3 across the study period (first year: 59.21 ± 33.56; mid-study: 30.51 ± 11.77; final year: 37.71 ± 53.64), persistently exceeding safety standards. Three-year cumulative exposure showed significant association with higher MS incidence (IRR = 1.027, 95%CI = 1.022–1.031, p ConclusionLong-term exposure to PM2.5 is associated with an increased incidence of MS and disease progression, emphasizing the critical need for improved air quality management strategies.背景：多发性硬化（Multiple sclerosis, MS）是一类以自身免疫性炎症为核心特征的中枢神经系统退行性疾病。现有研究显示，环境因素尤其是空气污染，或可显著升高多发性硬化的发病风险。 研究目的：本研究旨在探讨作为空气污染评价指标的PM2.5（Particulate Matter 2.5）浓度，与伊朗伊斯法罕市多发性硬化发病率之间的关联——该市是伊朗境内报告的多发性硬化患病率最高的城市之一。 研究方法：本研究为回顾性人群队列研究，采用2011—2021年伊朗国家多发性硬化登记系统及伊斯法罕市空气污染监测部门的相关数据开展分析。研究人员计算了各城区的多发性硬化发病率，并通过泊松广义回归模型（Poisson generalized regression models）评估PM2.5浓度与多发性硬化发病风险比（Incidence Rate Ratio, IRR）之间的关联。 研究结果：研究期间全市PM2.5平均浓度为41.99 µg/m³（首年：59.21±33.56；研究中期：30.51±11.77；终期：37.71±53.64），持续超出国家空气质量安全限值。三年累积暴露量与多发性硬化发病率升高呈显著正相关（IRR=1.027，95%置信区间=1.022–1.031，P[原文未完整给出具体统计值]）。 研究结论：长期PM2.5暴露与多发性硬化发病率升高及疾病进展显著相关，凸显了优化空气质量管控策略的迫切性与必要性。