Impact of <scp>UVA</scp> on pruritus during <scp>UVA</scp> /B phototherapy of inflammatory skin diseases: a randomized double‐blind study

Abstract

BACKGROUND: Narrowband (TL-01) UVB phototherapy (UVB nb) is effective in treating inflammatory skin disease. The addition of UVA is traditionally advocated to reduce pruritus, but lacks evidence for this recommendation. OBJECTIVES: The aim of this study was to assess the effect of UVB nb and UVA phototherapy in combination compared against UVB nb monotherapy on pruritus, disease activity and quality of life. METHODS: In this double-blind randomized clinical trial, 53 patients suffering from inflammatory skin diseases with pronounced itching (Visual Analogue Scale (VAS) for pruritus ≥5) were randomized into two treatment groups. One group received UVB nb (311 nm) phototherapy alone and another group received a combination of UVB nb and UVA (320-400 nm) phototherapy. UV therapy was performed three times per week over 16 weeks. Pruritus (VAS and 5-D itch score), disease activity and quality of life (Dermatology Life Quality Index, DLQI) were assessed at baseline and weeks 4, 8, 12 and 16. RESULTS: In both treatment groups, there was a reduction in pruritus scores, disease activity and DLQI. No difference in pruritus score, disease activity and quality of life could be detected between the group receiving UVB nb alone and those receiving UVB nb combined with UVA. CONCLUSIONS: Phototherapy with UVB nb alone, and UVB nb combined with UVA are equally effective in treating inflammatory skin disease and indifferent in reducing disease-associated pruritus. Given this non-inferiority for UVB nb monotherapy, the recommendation of adding UVA to UVB nb phototherapy for pruritic inflammatory skin disease should be abandoned.