OBJECTIVES
To evaluate vitamin D status in patients with basal cell nevus syndrome (BCNS) who practice photoprotection because of their genetic predisposition to skin cancer and to determine risk factors for deficiency.
DESIGN
Retrospective cohort study.
SETTING
Academic medical centers.
PATIENTS
Forty-one ambulatory patients with BCNS who participated in a 2-year chemoprevention clinical trial. Population-based controls (n = 360) were selected and matched by age, sex, Fitzpatrick skin type, and season/geography.
MAIN OUTCOME MEASURES
Levels of 25-hydroxyvitamin D (25[OH]D) and vitamin D deficiency (defined as a 25[OH]D level of ≤20 ng/mL).
RESULTS
Twenty-three patients with BCNS (56%) were vitamin D deficient. Patients with BCNS had mean 25(OH)D levels below those of the general population (-3 ng/mL; P = .02) and were 3 times more likely to be vitamin D deficient (56% vs 18%; P < .001). Levels of 25(OH)D were lower in patients who were overweight (-3.0 ng/mL; P = .04) and who had blood collected in the winter compared with the summer (-7.1 ng/mL; P < .001).
CONCLUSION
Patients with BCNS may be at increased risk for vitamin D deficiency, depending on their adherence to photoprotection practices.