Parental sun-protective regimens and prevalence of common melanocytic naevi among 7-year-old children in Sweden: changes over a 5-year period

Abstract

Common melanocytic naevi and cutaneous malignant melanoma share a common risk profile, influenced by ultraviolet radiation exposure. A high density of common melanocytic naevi correlates with an increased lifetime risk of developing cutaneous malignant melanoma. Effective strategies for sun protection, starting in early childhood, are considered of great importance to reduce the steadily rising melanoma trend. To investigate the 5-year changes in sun tanning habits, sun-protective regimens and density of common melanocytic naevi between two age-standardized populations of children. Population-based cross-sectional study performed among 7-year-old children in southern Sweden in 2002 and 2007. The parents answered a questionnaire and all children were examined by the same, trained research nurse. In total, 1190 children were enrolled: 681 in 2002 and 509 in 2007. The results showed that sun-protective regimens, such as use of sunscreen (+29%), clothing (+30%), staying in the shade (+123%) or indoors (+136%) during peak sun hours, had all increased significantly (P<0·0001). Travelling to sunny seaside holiday resorts abroad before the age of 2years had almost doubled (P<0·0001). The adjusted mean number of naevi per square metre body surface was significantly (P<0·0001) lower in 2007: 6·6 [95% confidence interval (CI) 5·6-7·6], compared with 11·0 (95% CI 10·0-12·0) in 2002. This study demonstrates increased self-reported parental actions for sun protection of young Swedish children in recent years; in consistency, lower numbers of common melanocytic naevi were observed. Results support the use of common melanocytic naevi as an objective measure of sun exposure in children.