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Published on: May 28, 2013
Narrowband versus broadband ultraviolet B phototherapy for adults with moderate-to-severe atopic dermatitis: a
Aaron M Drucker1,2,3,4, Yuan Zhong5, George Tomlinson3,6
1Department of Medicine and Research and Innovation Institute, Women's College Hospital, Toronto, ON, Canada.
Background:
Ultraviolet B (UVB) phototherapy is recommended in clinical guidelines for atopic dermatitis, but it is uncertain whether narrowband or broadband UVB is more effective and better tolerated.
Objectives:
To compare, in a parallel-group randomized clinical trial, the efficacy and safety of broadband with narrowband UVB for the treatment of moderate-to-severe atopic dermatitis.
Methods:
Participants were aged ≥ 18 years and had moderate-to-severe atopic dermatitis that was refractory to topical corticosteroid treatment. Participants were randomized 1 : 1 via a centralized computer randomization scheme to full-body broadband or narrowband UVB phototherapy, with ongoing concomitant topical therapy. Participants were blinded to the treatment, but the treating and assessing clinicians were not. The primary outcome was change in Eczema Area and Severity Index (EASI) at 12 weeks. Secondary outcomes included achieving 0 or 1 and an improvement of ≥ 2 on the validated Investigator Global Assessment for Atopic Dermatitis scale (vIGA-ADTM) and change in Patient-Oriented Eczema Measure (POEM), Peak Pruritus Numeric Rating Scale (PP-NRS), Dermatology Life Quality Index (DLQI) and Recap of atopic eczema (RECAP). Efficacy analyses were conducted on a modified intention-to-treat (ITT) population, including all randomized participants who received at least one dose of phototherapy. The trial was registered with ClinicalTrials.gov (NCT04818138).
Results:
Thirty-four participants were randomized to broadband UVB and 35 to narrowband UVB. Thirty-two participants received at least one dose of broadband UVB and 34 received at least one dose of narrowband UVB and were included in the modified ITT analysis. The mean (SD) patient age was 37.1 (15.9) years in the broadband UVB arm and 33.2 (12.1) in the narrowband UVB arm. The mean change in EASI score in the broadband UVB arm was -8.1 [95% credible interval (CrI) -12.1 to -4.1] and in the narrowband UVB arm it was -8.9 (95% CrI -13.0 to -4.9). In the adjusted analysis, the difference between arms in change in EASI was -0.7 (95% CrI -5.6 to 4.1). There were no significant differences between arms for vIGA, POEM, PP-NRS, DLQI or RECAP. Four patients withdrew from phototherapy due to adverse events in the broadband arm; none withdrew from the narrowband arm.
Conclusions:
In this study, broadband and narrowband UVB were similarly effective for the treatment of moderate-to-severe atopic dermatitis. Narrowband UVB was better tolerated.
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