Wellcome Trust Centre for Human Genetics and Department of Clinical Neurology, University of Oxford, Oxford, UK.
Neurology. 2011 Feb 1;76(5):425-31. doi: 10.1212/WNL.0b013e31820a0a9f.
French farmers and their families constitute an informative population to study multiple sclerosis (MS) prevalence and related epidemiology. We carried out an ecological study to evaluate the association of MS prevalence and ultraviolet (UV) radiation, a candidate climatologic risk factor.
Mean annual and winter (December-March) UVB irradiation values were systematically compared to MS prevalence rates in corresponding regions of France. UVB data were obtained from the solar radiation database (SoDa) service and prevalence rates from previously published data on 2,667 MS cases registered with the national farmer health insurance system, Mutualité Sociale Agricole (MSA). Pearson correlation was used to examine the relationship of annual and winter UVB values with MS prevalence. Male and female prevalence were also analyzed separately. Linear regression was used to test for interaction of annual and winter UVB with sex in predicting MS prevalence.
There was a strong association between MS prevalence and annual mean UVB irradiation (r = -0.80, p < 0.001) and average winter UVB (r = -0.87, p < 0.001). Both female (r = -0.76, p < 0.001) and male (r = -0.46, p = 0.032) prevalence rates were correlated with annual UVB. Regression modeling showed that the effect of UVB on prevalence rates differed by sex; the interaction effect was significant for both annual UVB (p = 0.003) and winter UVB (p = 0.002).
The findings suggest that regional UVB radiation is predictive of corresponding MS prevalence rates and supports the hypothesis that sunlight exposure influences MS risk. The evidence also supports a potential role for gender-specific effects of UVB exposure.
法国农民及其家属是研究多发性硬化症（MS）患病率和相关流行病学的信息人群。我们进行了一项生态学研究，以评估 MS 患病率与紫外线（UV）辐射之间的关联，紫外线辐射是候选的气候风险因素。
系统比较了相应法国地区的年平均和冬季（12 月至 3 月）UVB 辐照值与 MS 患病率。UVB 数据来自太阳辐射数据库（SoDa）服务，患病率来自先前在国家农民健康保险系统 Mutualité Sociale Agricole（MSA）登记的 2667 例 MS 病例的数据。使用 Pearson 相关系数来检验年度和冬季 UVB 值与 MS 患病率之间的关系。还分别分析了男性和女性的患病率。线性回归用于测试年度和冬季 UVB 与性别在预测 MS 患病率方面的交互作用。
MS 患病率与年平均 UVB 辐照（r = -0.80，p < 0.001）和平均冬季 UVB（r = -0.87，p < 0.001）之间存在很强的关联。女性（r = -0.76，p < 0.001）和男性（r = -0.46，p = 0.032）患病率均与年 UVB 相关。回归建模表明，UVB 对患病率的影响因性别而异；年 UVB（p = 0.003）和冬季 UVB（p = 0.002）的交互效应均显著。
这些发现表明，区域 UVB 辐射可预测相应的 MS 患病率，并支持阳光照射影响 MS 风险的假说。该证据还支持 UVB 暴露对性别特异性影响的潜在作用。
