Effect of Selenium Supplementation on Cardiometabolic Risk Factors in Polycystic Ovary Syndrome (PCOS) Patients: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background: Polycystic ovary syndrome (PCOS) has been shown to be associated with cardiometabolic risk factors. Selenium (Se) is a naturally occurring mineral trace element that constitutes an essential component of selenoproteins and plays a vital role in antioxidant defense. This systematic review and meta-analysis aims to assess the effects of selenium supplementation on cardiometabolic risk factors in patients with PCOS.Methods: MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases were searched up to March 2023 for randomized clinical trials that evaluated the effect of oral selenium supple-mentation on patients with PCOS. We employed a random-effects model to generate pooled estimates and 95% confidence intervals (CI).Results: Seven trials published between 2015 and 2022 were included. All the included studies were double blind, placebo-controlled trials. Selenium supplementation resulted in a significant decrease in VLDL (SMD =-0.35, 95% CI:-0.65;-0.05), MDA (SMD =-0.89, 95% CI:-1.21;-0.57) and hs-CRP (SMD =-0.38, 95% CI:-0.73;-0.03), as well as a significant increase in QUICKI (SMD = 0.78, 95% CI: 0.47; 1.09). The current meta-analysis did not find any significant changes in FPG, insulin, HOMA-IR, TC, TG, HDL, LDL, TAC, GSH, NO, SHBG, total testosterone, or mFG score for PCOS patients following selenium supplementation compared to placebo.Conclusion: Selenium supplementation may serve as a good adjunct therapy in patients with PCOS to decrease lipid peroxidation and inflammatory status. Moreover, selenium may improve insulin sensitivity in these pa-tients. However, the overall effects of selenium on all cardiometabolic risk factors in PCOS patients still need to be evaluated through large population and long duration RCTs.