COVID-19 and vitamin D (Co-VIVID study): a systematic review and meta-analysis of randomized controlled trials.

Introduction: Vitamin D levels have been reported to be associated with COVID-19 susceptibility, severity, and mortality events. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the use of vitamin D intervention on COVID-19 outcomes.

Areas Covered: Literature search was conducted using PubMed, Cochrane library, and ClinicalTrials.

Maternal serum irisin levels in normotensive and preeclamptic pregnancies: a systematic review and meta-analysis.

Background: Altered irisin levels have been reported in pregnancy-associated disorders, such as preeclampsia.

Objective: A systematic review and meta-analysis were conducted to evaluate the changes in maternal circulatory irisin levels in preeclampsia as compared to normotensive healthy pregnant controls.

Methods: Relevant studies were identified by searching PubMed and other databases.

Effect of metformin intervention on circulating irisin levels in polycystic ovary syndrome: a systematic review and collaborative meta-analysis.

Background: Irisin is an adipo-myokine with potential implications in metabolic disorders such as polycystic ovary syndrome (PCOS). Despite of a strong evidence showing increased irisin level in PCOS, there is no conclusive evidence on the effect of metformin intervention on circulatory irisin in PCOS.

Aim: The aim of this meta-analysis was to compare the circulatory (serum/plasma) irisin levels before and after metformin intervention in subjects with PCOS.