Bleach baths for atopic dermatitis A systematic review and meta-analysis including unpublished data, Bayesian interpretation, and GRADE

Background: Bleach bathing is frequently recommended to treat atopic dermatitis (AD), but its efficacy and safety are uncertain. Objective: To systematically synthesize randomized controlled trials (RCTs) addressing bleach baths for AD. Methods: We searched MEDLINE, EMBASE, CENTRAL, and GREAT from inception to December 29, 2021, for RCTs assigning patients with AD to bleach vs no bleach baths. Paired reviewers independently and in duplicate screened records, extracted data, and assessed risk of bias (Cochrane version 2) and GRADE quality of evidence. We obtained unpublished data, harmonized individual patient data and did Frequentist and Bayesian randomeffects meta-analyses. Results: There were 10 RCTs that enrolled 307 participants (median of mean age 7.2 years, Eczema Area Severity Index baseline mean of means 27.57 [median SD, 10.74]) for a median of 6 weeks (range, 4-10). We confirmed that other trials registered globally were terminated. Bleach baths probably improve AD severity (22% vs 32% improved Eczema Area Severity Index by 50% [ratio of means 0.78, 95% credible interval 0.59-0.99]; moderate certainty) and may slightly reduce skin Staphylococcal aureus colonization (risk ratio, 0.89 [95% confidence interval, 0.73-1.09]; low certainty). Adverse events, mostly dry skin and irritation, along with itch, patient-reported disease severity, sleep quality, quality of life, and risk of AD flares were not clearly different between groups and of low to very low certainty. Conclusion: In patients with moderate-to-severe AD, bleach baths probably improve clinician-reported severity by a relative 22%. One in 10 will likely improve severity by 50%. Changes in other patient-important outcomes are uncertain. These findings support optimal eczema care and the need for additional large clinical trials. (C) 2022 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Automated summary

In patients with moderate-to-severe atopic dermatitis, bleach baths likely improve clinician-reported severity, with approximately 10% of patients experiencing a 50% improvement. The impact on other patient-important outcomes remains uncertain. These findings highlight the need for further large-scale clinical trials.