Past exposure to sun, skin phenotype, and risk of multiple sclerosis: case-control study

作者：Ingrid A.F. van der Mei, A-L Ponsonby, Terence Dwyer, Leigh Blizzard, Rex D. Simmons, Bruce Taylor, Helmut Butzkueven, Trevor John Kilpatrick · 发表于：BMJ · 年份：2003 · DOI：10.1136/bmj.327.7410.316 · 被引用次数：555 · 研究领域：Multiple Sclerosis Research Studies、Effects of Radiation Exposure、Ophthalmology and Visual Impairment Studies

OBJECTIVE: To examine whether past high sun exposure is associated with a reduced risk of multiple sclerosis. DESIGN: Population based case-control study. SETTING: Tasmania, latitudes 41-3 degrees S. PARTICIPANTS: 136 cases with multiple sclerosis and 272 controls randomly drawn from the community and matched on sex and year of birth. MAIN OUTCOME MEASURE: Multiple sclerosis defined by both clinical and magnetic resonance imaging criteria. RESULTS: Higher sun exposure when aged 6-15 years (average 2-3 hours or more a day in summer during weekends and holidays) was associated with a decreased risk of multiple sclerosis (adjusted odds ratio 0.31, 95% confidence interval 0.16 to 0.59). Higher exposure in winter seemed more important than higher exposure in summer. Greater actinic damage was also independently associated with a decreased risk of multiple sclerosis (0.32, 0.11 to 0.88 for grades 4-6 disease). A dose-response relation was observed between multiple sclerosis and decreasing sun exposure when aged 6-15 years and with actinic damage. CONCLUSION: Higher sun exposure during childhood and early adolescence is associated with a reduced risk of multiple sclerosis. Insufficient ultraviolet radiation may therefore influence the development of multiple sclerosis.