Effect of Traditional Chinese Medicine on Psoriasis Vulgaris: A Meta-Analysis and Systematic Review

BACKGROUND: Psoriasis is a chronic, inflammatory autoimmune skin disease that affects 2-3% of the world's population. Lesions are mainly found on the limbs, trunk, and scalp, but may also affect other parts of the body, and the cause is not yet known. The chronic and relapsing nature of psoriasis makes it one of the most complex and important diseases in current dermatology research. METHODS: The search was conducted using PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Internet, Wanfang Data, VIP journals database, and Chinese biomedical literature database (CBM). The retrieval time limit was from the establishment of the database to January 2021. The quality of the selected literature was evaluated, and ReView Manager 5.3 was used for meta-analysis after randomized controlled trials were filtered. RESULTS: Finally, 16 randomized controlled trials involving 1,967 patients were included. The total effective rate (OR = 3.68, 95% CI [2.73, 4.95], p < 0.00001), cure rate (OR = 2.01, 95% CI [1.62, 2.49], p < 0.00001), and PASI score (OR = -1.83, 95% CI [-2.39, -1.26], p < 0.00001) of the traditional Chinese medicine (TCM) were superior to the Diyin tablet. CONCLUSION: In the treatment of psoriasis, TCM shows higher efficacy than the Diyin tablet. However, due to the limitations of the included literature, we still need more double-blind, placebo-controlled trials with large samples and multiple centers to provide high-quality clinical evidence.