TY - JOUR T1 - Past exposure to sun, skin phenotype, and risk of multiple sclerosis: case-control study. AU - van der Mei,I A F, AU - Ponsonby,A-L, AU - Dwyer,T, AU - Blizzard,L, AU - Simmons,R, AU - Taylor,B V, AU - Butzkueven,H, AU - Kilpatrick,T, PY - 2003/8/9/pubmed PY - 2003/8/26/medline PY - 2003/8/9/entrez SP - 316 EP - 316 JF - BMJ (Clinical research ed.) JO - BMJ VL - 327 IS - 7410 N2 - 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. SN - 1756-1833 UR - https://www.unboundmedicine.com/medline/citation/12907484/full_citation DB - PRIME DP - Unbound Medicine ER -