Introduction: The antiinflammatory and antioxidative effects of melatonin have been established in recent years. Several studies indicate that oxidative stress and inflammation are key drivers of post-coronary artery bypass graft (CABG) surgery complications. In the present study, we aimed to investigate the effects of melatonin on cardiac injury and inflammatory biomarkers in CABG candidates.
Methods: Embase, Medline/PubMed, Web of Science, Scopus, and the Cochrane library were searched up to 5 June 2022. All randomized controlled trials examining cardiac injury and inflammatory biomarkers of CABG patients who received melatonin were included. The random-effects model was utilized to perform the analysis.
Results: A total of 947 citations were retrieved through database searches. Finally, five articles (six trials with 342 patients) were included after the screening. Melatonin supplementation led to a significant reduction in cardiac troponin I (CTnI) [weighted mean difference(WMD): -2.28 ng/ml; 95% CI -2.87, -1.69; P < 0.01; I2: 91.25%] and high sensitivity-C reactive protein (hs-CRP) levels (WMD: -0.62 mg/L; 95% CI -0.73, -0.5; P < 0.01; I2: 99.98%) in patients undergoing CABG surgery. We found a nonsignificant decrease in creatine kinase isoenzyme muscle/brain (CK-MB) levels (WMD: -2.87 ng/ml; 95% CI -5.97, 0.23; P = 0.07; I2: 99.98%) after melatonin supplementation. No publication bias was found according to Egger's test.
Conclusion: Melatonin supplementation may be useful in reducing cardiac injury and inflammatory biomarkers in CABG candidates. Future studies should investigate the clinical significance of these findings.
Keywords: C-reactive protein; Coronary artery bypass; Creatine kinase MB form; Melatonin; Meta-analysis; Troponin I.
© 2022. The Author(s).