Westberg M, Feychting M, Jonsson F, Nise G, Gustavsson P
Department of Occupational and Environmental Health, Stockholm Centre for Public Health, Stockholm, Sweden.
Am J Ind Med. 2009 May;52(5):353-7. doi: 10.1002/ajim.20682.
The etiology of multiple sclerosis (MS) is largely unknown; low exposure to ultraviolet (UV) light has been a suggested risk factor. The aim of this study was to investigate whether occupational exposure to UV light reduces the risk of death from MS.
The cohort was based on all individuals in the Swedish census in 1980. All MS-related deaths were identified in the national registry of causes of death. A job-exposure matrix was developed to classify the occupational exposure to UV light.
MS was recorded as a cause of the death for 839 individuals. The risk of MS-related death decreased with increasing occupational exposure to UV light. The relative risk adjusted for age, sex, and socioeconomic status was 0.48 (95% CI 0.28-0.80) in the high-exposure group and 0.88 (95% CI 0.73-1.06) in the intermediate-exposure group.
Occupational exposure to UV light was associated with a reduced risk of MS. Our findings are corroborated by previous observations that UV light has a preventive role in the development of MS, although the possibility of reversed causality cannot be completely ruled out.
多发性硬化症（MS）的病因很大程度上尚不清楚；紫外线（UV）暴露较少被认为是一个风险因素。本研究的目的是调查职业性紫外线暴露是否能降低死于MS的风险。
该队列基于1980年瑞典人口普查中的所有个体。在国家死亡原因登记处确定了所有与MS相关的死亡病例。开发了一个工作暴露矩阵来对职业性紫外线暴露进行分类。
839人被记录为死于MS。与MS相关的死亡风险随着职业性紫外线暴露的增加而降低。在高暴露组中，经年龄、性别和社会经济地位调整后的相对风险为0.48（95%CI 0.28 - 0.80），在中等暴露组中为0.88（95%CI 0.73 - 1.06）。
职业性紫外线暴露与MS风险降低有关。尽管不能完全排除反向因果关系的可能性，但我们的研究结果得到了先前观察结果的证实，即紫外线在MS的发生发展中具有预防作用。
