Clinical question
Are indoor salt water baths followed by exposure to artificial ultraviolet B light beneficial for treating chronic plaque psoriasis in adults?
Bottom line
Salt water baths plus artificial UVB light may improve psoriasis in people with chronic plaque psoriasis compared with UVB light treatment alone (risk ratio 1.71; 95% confidence interval 1.24–2.35). This was based on the psoriasis area and severity index-75, which is a 75% or more reduction in PASI score from baseline. The number needed to treat to benefit 1 individual was 5.
There may be no difference in the occurrence of treatment‐related adverse events requiring withdrawal (RR 0.96; 95% CI 0.35–2.64).
Caveat
The quality of evidence for the primary outcome, PASI‐75, was judged as low due to lack of blinding and high probability of publication bias. Six studies included in the review did not contribute to the primary outcome. The 2 studies that did contribute data were conducted by the same sponsor. The outcome of treatment‐related adverse events requiring withdrawal was also graded as low quality, again due to lack of blinding and publication bias as only 3 of the 8 studies reported this outcome.
Context
Chronic plaque psoriasis is an immune‐mediated, chronic, inflammatory skin disease that can impair quality of life and social interaction. Disease severity can be classified by the PASI score, ranging from 0 to 72 points. Indoor artificial salt water baths with or without artificial UVB light are used to treat psoriasis, simulating sea bathing and sunlight exposure; however, the evidence base needed clear evaluation.
Cochrane Systematic Review
Peinemann F, et al. Indoor salt water baths followed by artificial ultraviolet B light for chronic plaque psoriasis. Cochrane Database Syst Rev 2020, Issue 5. Art. No.: CD011941. DOI: 10.1002/14651858.CD011941.pub2. This review contains 8 trials with a total of 2105 participants.
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