The Role of Vitamin D in Carpal Tunnel Syndrome Risk and Supplementation Outcomes: A Systematic Review

Abstract

Background: Carpal tunnel syndrome (CTS) is a debilitating neuropathy that accompa-nies pain and other physical limitations and disrupts the normal functioning of the victims' lives. Objective: We aimed to investigate Vitamin D's preventive and therapeutic effects on the occur-rence and remission of CTS symptoms. Methods: In this systematic review the PRISMA statement has been designed primarily. An exten-sive search was undertaken in various databases, including PubMed, Cochrane library, Web of Sci-ence, EMBASE, and Scopus. After considering the inclusion and exclusion criteria of the study, fi-nally, 19 articles were retrieved. The raw data were extracted and entered into an Excel form, and the study outcomes were investigated. Results: The main symptoms and tests, including functional score, nerve conduction, and pain, were improved after Vitamin D supplementation in CTS patients. However, they revealed worse scores in people with low Vitamin D levels. In addition, the scores of mentioned indices were worsened in people with lower serum Vitamin D levels. Nevertheless, some studies did not find a significant re-lationship between low serum 25(OH)D and more significant pain scores in CTS patients. In addi-tion, Vitamin D inserts its effects on CTS by regulating cell proliferation, nerve growth factor, sup-pression of oxidative stress and inflammatory cytokines, and improvement in cartilage and micro-vascular damage. Conclusion: Vitamin D supplementation can improve the symptoms in CTS patients, and low se-rum 25(OH)D can aggravate the symptoms of the disease and could be a risk factor for its occur-rence. However, more observational studies and clinical trials are needed.