Melanoma risk in relation to use of sunscreen or other sun protection methods
Cette étude américaine (1 167 cas et 1 101 témoins) évalue l'association entre différentes stratégies de protection solaire (rester à l'ombre, utiliser de la crème solaire, des vêtements couvrant, un chapeau) et le risque de mélanome
Background:Epidemiologic evidence supporting sunscreen for melanoma prevention is limited to one small trial; case-control studies report conflicting results. Sunscreen usage patterns or alternative sun protection methods have rarely been studied in relation to melanoma. Methods:In a population-based case-control study, participants (1167 cases, 1101 controls) reported for each decade year of age outdoor activity-related sunscreen use, sunscreen patterns (SPF15+, amount, skin coverage, re-application, routine use), and use of other sun protection methods (like hats, long-sleeved shirts, staying in the shade). Scores were averaged across activities and/or decades; scores in the most recent two decades were used to classify individuals as non-, inconsistent- or optimal users. Adjusted mean score differences between cases and controls, and ORs and 95% CIs for melanoma among optimal-, inconsistent- versus non-users were calculated. Results:Mean scores for sunscreen, sunscreen patterns or other sun protection methods were low, but higher among controls than cases for SPF15+ sunscreen (p=0.03) and other sun protection methods (p=0.006). Adjusted ORs for optimal use of sunscreen and most sunscreen patterns were null or relatively weak, except for routine sunscreen (aOR=0.44, 95% CI 0.23-0.86). Optimal use of other sun protection methods was inversely associated with melanoma (aOR=0.59, 95% CI 0.44-0.78). Conclusions:Optimal use of routine sunscreen or other sun protection methods were most strongly associated with decreased melanoma risk; results are limited by the small number of subjects who used sunscreen routinely and lack of specificity regarding other sun protection methods. Impact:Both improving sunscreen practices and encouraging sun avoidance strategies may be important for melanoma prevention.