Interventional study in 1,232 young German children to prevent the development of melanocytic nevi failed to change sun exposure and sun protective behavior

Abstract

Sunscreens have been proposed as protective measures to inhibit the development of melanocytic nevi in childhood and to decrease the long term risk for cutaneous melanoma development. Our present study investigates the influence of sunscreen use and education on the number of incident melanocytic nevi. A total of 1,812 children in 78 public nursery schools in 2 German cities were randomized to 3 study arms: (i) parents were informed on study purpose and sun protection measures only at an initial educational meeting; (ii) parents received educational material 3 times yearly; and (iii) education and 800 ml free broad spectrum sunscreens with sun protection factor 25 provided on a yearly basis. Final assessment after 3 years follow-up included 1,232 children (68%). Changes of sun protection habits including sunscreen use were sparse, without any differences attributable to the intervention efforts. As a consequence, there were no significant differences between the 3 study arms for the main outcome measure, the number of incident melanocytic nevi. Analysis of the sunscreen use in the entire cohort irrespective of our study arms did not show any impact on incident nevus numbers in bivariate or multivariate analysis. In conclusion, intervention with educational letters and free sunscreens seemingly had no additional effect on sun-protection for German children. High prevalence of sunscreen use at study commencement, social desirability, and inadequate application of sunscreens might have partially covered their effect. ' 2005 Wiley-Liss, Inc.Key words: melanocytic nevi; prevention and control; child; sunscreens; intervention studies Exposure to ultraviolet light in childhood as well as in adulthood is the central environmental risk factor for cutaneous melanoma (CM).1-4 The use of sunscreen is intended to avoid sunburn as well as to reduce the risk of CM. Numerous case-control studies focusing on the effect of sunscreen use and the risk of CM reported contradicting results reaching from a reduced risk, 5-8 an unchanged risk, 9 to an increased risk in persons using sunscreen.10-17 Most of these case-control studies were hospitalbased, might not have been controlled comprehensively for exposure to sunlight and skin type and were most likely influenced by recall bias, as they involved melanoma patients. Meta-analyses of studies published recently on the relationship of sunscreen use and the risk of CM could not find any association. 18-21The number of melanocytic nevi (MN) is known to be the strongest risk factor for CM. Nevi are precursor lesions of a substantial proportion of 20-60% of CM. 22 Humans develop MN from an early age onward and numerous studies have investigated the development of MN in children. 1,[23][24][25][26][27][28][29][30] Studying sunscreen use in children and its relationship to MN should be less influenced by recall bias. Thus far, however, investigations of sun protective behavior in children have not shown conclusive evidence for either a protective or harmful effect of sunscreen. [31][32][33][...

Sunscreen use and increased duration of intentional sun exposure: Still a burning issue

“…25 The German trial failed to change patterns of sunscreen use between the randomization groups because apparently, sunscreen use was already highly prevalent in all groups at study start. 26 The Vancouver trial reported estimations of the total amounts of time spent in the sun during the 3-year trial duration but did not report duration of sun exposure per day with or without sunscreen use.…”

“…25,26 The Vancouver trial in Canada found a reduction in the development of new nevi in children with dense facial freckling and found no effect in children without dense facial freckling. 25 The German trial failed to change patterns of sunscreen use between the randomization groups because apparently, sunscreen use was already highly prevalent in all groups at study start.…”

Development of sun protection behaviors in preschoolers: A systematic review

“…This systematic review evaluated five research articles chosen according to the study criteria (Table 1) [29][30][31][32][33] . The results obtained from the studies were grouped under the headings of "Research groups and characteristics", "Characteristics of program applied", "Evaluation of program applied", "Results obtained", and "Methodological quality of the studies", all of which are described in greater detail below.…”

“…All the studies were RCTs conducted between 1995 and 2007, with four being carried out in the United States of America 9,30,32,33 and one in Germany 31 . Regarding the samples of the studies included in the research, two consisted of children 29,31 one of parents 32 , and one of preschool personnel 33 , parents, and school principals 30 .…”

Evaluation of sun protection behaviour in patients following excision of a skin lesion

“…Bauer et al (11) reported an interventional study to decrease the incidence of melanocytic nevi in 1232 German children. The authors investigated the efficacy of education and free sunscreen on decreasing the incidence of melanocytic nevi three years following their intervention.…”