Predictive Model for Response Rate to Narrowband Ultraviolet B Phototherapy in Vitiligo: A Retrospective Cohort Study of 579 Patients
Raúl Cabrera, Lia Hojman, Francisca Recule, Rodrigo Sepulveda, Iris Delgado
Vitiligo is an acquired depigmenting disorder. To date, there is no predictive model for its response rate to narrowband ultraviolet B (NBUVB) phototherapy. The aim of this study was to investigate the different types of response of patients with non-segmental vitiligo undergoing NBUVB 3 times a week. Many patients who were previously considered non-responders were given the opportunity to continue the treatment. Long-term maintenance of treatment and follow-up of a cohort of 579 patients enabled different subtypes of response (very rapid, rapid, average, slow and “non-responders”) to be described for the first time, and a predictive model of response to be constructed based on repigmentation rate in the first 48 sessions of NBUVB. Among those patients who did not respond during the first 48 sessions, a new subgroup of patients was found, termed “very-slow” responders, who achieved a low, but significant, level of repigmentation after 96 sessions of NBUVB.