A recent Cochrane review suggests very few studies offer sufficient evidence supporting the efficacy and safety of exposure to artificial ultraviolet (UV) B while soaking in an indoor salt bath, an approach termed balneophototherapy, for the treatment of chronic plaque psoriasis. Abridged findings from this review were published in the British Journal of Dermatology.
An international team of researchers reviewed 8 randomized controlled trials consisting of 1976 participants with psoriasis. In 6 trials, different treatments were applied to different participants, whereas 2 other trials examined different treatments applied to the same participant but to different body parts.
Across all studies, the mean age for participants ranged between 41 to 50 years, and the median Psoriasis Area and Severity Index (PASI) score ranged from 15 to 18 across 5 studies. Only 1 trial examined salt baths plus UVB vs other treatments without UVB (ie, psoralen bath plus UVA). Trials spanned from 2 to 13 months in duration.
Several limitations affected the researchers’ confidence in the evidence of these trials. These limitations included risk for bias, such as in terms of inadequate blinding and high probability of publication bias. The researchers noted that commercial spa or salt companies sponsored 3 studies, health insurance companies sponsored 1 study, a dermatologist association sponsored 1 study, and 3 studies had no reported funding sources.
In addition, reporting of the reviewers’ specified outcomes – including Dermatology Life Quality Index, pruritus severity using a visual analogue scale from 0 (‘no itching’) to 100 (severe itching), time to relapse, and secondary malignancies – were either limited or nonexistent.
According to the researchers who conducted this Cochrane review, further randomized controlled trials are needed to evaluate PASI 75 and even PASI 90 or 100, in addition to treatment-related adverse events requiring withdrawal, to gain a deeper understanding of the efficacy and safety of balneophototherapy. “To consider any potential harm by UVB exposure,” they wrote, “future study protocols should include long-term observations.”
Dislcosure: Please see the original reference for a full list of authors’ disclosures.
Peinemann F, Harari M, Peternel S, et al. Indoor salt water baths followed by artificial ultraviolet B light for chronic plaque psoriasis: abridged Cochrane review. Published online July 6, 2020. Br J Dermatol. doi:10.1111/bjd.19385