Efficacy of combining oral Chinese herbal medicine and NB-UVB in treating psoriasis vulgaris: a systematic review and meta-analysis.

BACKGROUND The combination of a Chinese herbal medicine (CHM) bath and narrowband ultraviolet B (NB-UVB) improved the efficacy of NB-UVB treatment of psoriasis vulgaris, but bath therapy is inconvenient. Oral CHM plus NB-UVB has been tested in clinical practice. This study aims to evaluate whether adding oral CHM could be beneficial for NB-UVB therapy by a systematic review and meta-analysis. METHODS Nine English and Chinese databases were searched from their inception to April 2014. Randomized controlled trials (RCTs) comparing the combination of orally administered CHM and NB-UVB with that of CHM placebo and NB-UVB or NB-UVB alone for treating psoriasis vulgaris and reporting Psoriasis Area Severity Index (PASI) outcomes were included. A systematic review, meta-analysis, risk of bias assessment and the GRADE assessment were conducted in accordance with Cochrane Collaboration methodology to assess the evidence for efficacy outcome. Data were analyzed in RevMan5.2. RESULTS Eighteen eligible RCTs (n = 1416) were included for systematic review, and 17 (n = 1342) of them were included in meta-analysis. Risk of bias in terms of blinding was high and so was in publication bias. Quality of evidence was low according the GRADE assessment. PASI-60 or above [risk ratio (RR) = 1.35, 95 % confidence interval (CI) 1.26-1.45, I(2) = 5 %, number needed to treat = 4.27] and PASI-90 or above (RR = 1.71, 95 % CI 1.45-2.01, I(2) = 0 %, number needed to treat = 5.92) were higher in the intervention group. The combination treatment conferred a 24 % benefit of PASI-60 or above (83 vs 59 %, RR = 1.35, 95 % CI 1.26-1.45, P < 0.01). The incidence of NB-UVB-induced adverse events was lower in the intervention group (95/464 vs 123/428, RR = 0.66, 95 % CI 0.46-0.96, P < 0.01). Mild gastrointestinal reactions (2.87 %) and liver function impairments (0.68 %) were reported in the intervention group. No serious adverse events were reported. CONCLUSION The orally administrated CHM combined with NB-UVB in treating psoriasis vulgaris showed improved efficacy but quality of evidence was low.