Bath PUVA and Psoriasis: Is a Milder Treatment a Worse Treatment?

Abstract

Background/Aim: The guidelines of the British Photodermatology Group for topical treatment with psoralen and ultraviolet light (PUVA) recommend starting UVA doses between 0.2 and 0.5 J/cm², according to the phototype. Our purpose was to evaluate the therapeutic efficacy and tolerability of bath PUVA, with 8-methoxypsoralen (8-MOP), by using lower UVA doses, regardless of phototype. Methods: We compared 2 groups of patients (group 1: n = 10, group 2: n = 20) with chronic plaque-type psoriasis. Group 1 was treated with the usual starting dose and dose progression; group 2 was treated by using a lower first dose, a slower dose progression and reaching a lower maximum dose. The Psoriasis Area and Severity Index (PASI) score was assessed at the initial stages, and every month until the end of the treatment. Results: In group 1, the median baseline PASI score decreased from 15.2 to 4.5 (p < 0.005, Student’s paired t test), while in group 2, it fell from 13.7 to 4.1 (p < 0.005). No statistical difference between the groups is detectable. Severe phototoxic reactions were observed only in 2 patients of group 1. Side effects were not observed in group 2. Conclusions: Our data indicate that an aggressive bath PUVA treatment is not substantially more effective in clearing chronic plaque-type psoriasis than a milder therapeutic approach.