Abstract

BACKGROUND: Vitamin D may play a role in prevention of keratinocyte cancer (KC), but observational studies examining the association between serum 25-hydroxy vitamin D concentration and KC are largely uninformative because sun exposure causes both KC and vitamin D production. There is scant evidence from clinical trials of supplementary vitamin D. OBJECTIVES: To examine the effect of vitamin D supplementation on the risk of developing KC. METHODS: We used data from the D-Health Trial, a randomised placebo-controlled trial of vitamin D supplementation (60,000 IU monthly for 5?years) among Australians aged =60?years. KC outcomes were captured through linkage to a national administrative dataset for those who consented (N=20,334; 95%). We used negative binomial regression to analyse the incidence of KC excisions and the incidence of actinic lesions treated using cryotherapy or serial curettage, and flexible parametric survival models for analysis of time to first KC excision. RESULTS: Randomisation to vitamin D supplementation did not reduce the incidence of KC lesions treated by excision [incidence rate ratio (IRR) 1.04; 95% CI 0.98 - 1.11], the incidence of actinic lesions treated using other methods (IRR 1.01; 95% CI 0.95 - 1.08), or time to first histologically confirmed KC excision (hazard ratio 1.02; 95% CI 0.97 - 1.08). However, in subgroup analysis vitamin D increased the incidence of KC excisions in adults aged =70?years (IRR 1.13; 95% CI 1.04-1.23. p-value for interaction 0.01). CONCLUSION: Vitamin D supplementation did not reduce the incidence of KC or other actinic lesions.

Authors	Ali, Sitwat; Pham, Hai; Waterhouse, Mary; Baxter, Catherine; Romero, Briony Duarte; McLeod, Donald S A; Armstrong, Bruce K; Ebeling, Peter R; English, Dallas R; Hartel, Gunter; van der Pols, Jolieke C; Venn, Alison J; Webb, Penelope M; Whiteman, David C; Neale, Rachel E
Journal	BRITISH JOURNAL OF DERMATOLOGY
Pages	667-675
Volume	187
Date	1/01/2022
Grant ID
Funding Body
URL	http://www.ncbi.nlm.nih.gov/pubmed/?term=10.1111/bjd.21742