Probiotic supplementation improves clinical outcomes and quality of life indicators in patients with plaque psoriasis: A randomized double-blind clinical trial

The impact of probiotics on psoriasis, a systemic inflammatory disease, remains obscure, thus we decided to evaluate quality of life (QOL), oxidative stress, inflammatory markers and clinical outcome in psoriasis patients.Fifty patients with plaque psoriasis randomized into two groups, group 1 received probiotic drink with Lactobacillus strains for 8 weeks while group 2 haven't received any probiotic supplements at this period. The Dermatology Life Quality Index (DLQI) and Beck's questionnaire (BDI) were used to investigate the quality of life and depression, respectively. The effects of supplementation on malondialdehyde (MDA), hs-CRP, IL-6, total antioxidant capacity (1) and psoriasis area and severity index (PASI), psoriasis symptom scale (PSS) were measured at the beginning of the study and after week 8th.Total BDI scores significantly improved in the probiotic group in comparison with the placebo group (-6.15 ± 2.10 vs. 1.39 ± 1.80, P = 0.017) and DLQI (-9.50 ± 4.1 vs. 0.12 ± 0.6, P = 0.045) as well. Group 1 had a considerable reduction in PASI and PSS scores compared to the placebo group (-5.26 ± 3.75 vs. 0.48 ± 1.37, P = 0.049) and (-4.85 ± 3.10 vs. 0.43 ± 0.80, P = 0.047), respectively. In addition, the intervention group have shown increase in TAC levels (45.99 ± 23.33 vs -13.54 ± 30.7 mmol/L, P = 0.030), and decrease in hs-CRP levels (-1.55 ± 0.85 vs. -0.49 + 0.27 mg/L, P = 0.015), IL-6 levels (-4.04 ± 1.30 vs. -1.50 + 0.38 mg/L, P = 0.050) and MDA levels (-71.08 ± 35.73 vs. -9.8 + 15.6 nmol/mL, P = 0.013) compared to the placebo group.Probiotics improve patients' quality of life and inflammatory biomarkers in psoriatic patients. Further studies are mandatory to propose probiotics as routinely prescribed therapy in inflammatory dermatoses.This trial was registered at www.irct.ir as IRCT20180712040438N2.