Roux Jonathan, Bard Denis, Le Pabic Estelle, Segala Claire, Reis Jacques, Ongagna Jean-Claude, de Sèze Jérôme, Leray Emmanuelle
METIS Department, EA 7449 REPERES, EHESP French School of Public Health, Sorbonne Paris Cité, 15 avenue du Professeur Léon-Bernard - CS 74312, 35043 Rennes, France; INSERM CIC-P 1414, CHU of Rennes, 2 Rue Henri le Guilloux, 35000 Rennes, France.
METIS Department, EA 7449 REPERES, EHESP French School of Public Health, Sorbonne Paris Cité, 15 avenue du Professeur Léon-Bernard - CS 74312, 35043 Rennes, France.
Environ Res. 2017 Jul;156:404-410. doi: 10.1016/j.envres.2017.03.049. Epub 2017 Apr 11.
Seasonal variation of relapses in multiple sclerosis (MS) suggests that season-dependent factors, such as ambient air pollution, may trigger them. However, only few studies have considered possible role of air pollutants as relapse's risk factor.
We investigated the effect of particulate matter of aerodynamic diameter smaller than 10µm (PM) on MS relapses.
In total, 536 relapsing MS patients from Strasbourg city (France) were included, accounting for 2052 relapses over 2000-2009 period. A case-crossover design was used with cases defined as the days of relapse and controls being selected in the same patient at plus and minus 35 days. Different lags from 0 to 30 days were considered. Conditional logistic regressions, adjusted on meteorological parameters, school and public holidays, were used and exposure was considered first as a quantitative variable and second, as a binary variable.
The natural logarithm of the average PM concentration lagged from 1 to 3 days before relapse onset was significantly associated with relapse risk (OR =1.40 [95% confidence interval 1.08-1.81]) in cold season. Consistent results were observed when considering PM as a binary variable, even if not significant.
With an appropriate study design and robust ascertainment of neurological events and exposure, the present study highlights the effect of PM on the risk of relapse in MS patients, probably through oxidative stress mechanisms.
多发性硬化症（MS）复发的季节性变化表明，季节相关因素，如环境空气污染，可能引发复发。然而，只有少数研究考虑了空气污染物作为复发风险因素的可能作用。
我们研究了空气动力学直径小于10μm的颗粒物（PM）对MS复发的影响。
总共纳入了来自法国斯特拉斯堡市的536例复发型MS患者，这些患者在2000 - 2009年期间共有2052次复发。采用病例交叉设计，将病例定义为复发日，对照则在同一患者的复发日前后35天内选取。考虑了从0到30天的不同滞后时间。使用在气象参数、学校和公共假日进行调整的条件逻辑回归，暴露首先被视为定量变量，其次被视为二元变量。
在寒冷季节，复发前1至3天滞后的平均PM浓度的自然对数与复发风险显著相关（OR = 1.40 [95%置信区间1.08 - 1.81]）。当将PM视为二元变量时，观察到了一致的结果，尽管不显著。
通过适当的研究设计以及对神经学事件和暴露的可靠确定，本研究突出了PM对MS患者复发风险的影响，可能是通过氧化应激机制。
