Low ultraviolet B and increased risk of brain cancer: an ecological study of 175 countries.

摘要

BACKGROUND: The purpose of this study was to determine whether an inverse association exists between latitude, solar ultraviolet B (UVB) irradiance, modeled 25-hydroxyvitamin D [25(OH)D] levels and incidence rates of cancer of the brain. METHODS: Associations of latitude and UVB irradiance with age-standardized incidence rates of cancer of the brain were analyzed for 175 countries while controlling for proportion of population overweight, energy from animal sources, fish consumption, cigarette and alcohol consumption and per capita health expenditures, using multiple regression. Serum 25(OH)D levels were modeled for each country, and their association with brain cancer also was determined. RESULTS: The incidence rates of brain cancer were higher at higher latitudes (R(2) for males = 0.45, p