Upper extremity moles were associated with a 37% increase in the likelihood of vitiligo among white women, according to an analysis of the prospective Nurses’ Health Study.
“Women with a higher tanning ability and women who had a history of blistering sunburns in childhood were also found to have a higher risk of developing vitiligo,” Rachel Dunlap, MD, of the department of dermatology, Brown University in Providence, R.I., and her associates wrote in the Journal of Investigative Dermatology.
Vitiligo is the most common cutaneous depigmentation disorder, but associated risk factors are poorly understood, the investigators noted. They examined ties between skin pigmentation, reactions to sun exposure, and new onset vitiligo in the Nurses’ Health Study, a population-based prospective cohort study. Study participants were asked to report the number of moles on their left arms measuring at least 3 mm in diameter, their reactions to sunburn and ability to tan during childhood, and whether they had vitiligo diagnosed by a physician. A total of 51,337 women answered the question about moles, and 68,590 women answered the question about vitiligo, the investigators said (J Invest Dermatol. 2017 Feb 14. doi: 10.1016/j.jid.2017.02.004).
A total of 271 cases of vitiligo developed over 835,594 person-years. Women who reported at least one left arm mole larger than 3 mm were significantly more likely to report incident vitiligo, compared with women without moles (hazard ratio, 1.37; 95% confidence interval, 1.02-1.83), even after controlling for age, hair color, history of exposure to direct sunlight, skin tanning ability, and severity of reaction to sunburn. Developing an “average” tan or a “deep” tan after prolonged sun exposure also were significantly associated with vitiligo with hazard ratios of 2.28 (95% CI, 1.12-4.65) and 2.59 (95% CI, 1.21-5.54), respectively, “when compared to those who had minimal skin reactions or less severe burns when exposed to the sun,” the authors wrote.
A history of at least one blistering sunburn after 2 hours of sun exposure also predicted vitiligo (HR, 2.17; 95% CI, 1.15-4.10), while hair color did not.
“The benefits of good sun protection can be expanded to include potential vitiligo prevention, which may be particularly applicable to adult patients with vitiligo who are concerned about their children developing the condition,” the investigators commented. “Future studies will examine the incidence of other influencing factors, such as melanoma and melanoma associated leukoderma in this population.”
External funding sources included the National Institutes of Health and Dermatology Foundation. The investigators reported having no conflicts of interest.