Zinc status and coronary artery disease: A systematic review and meta-analysis

The association between serum zinc (Zn) levels and coronary artery disease (CAD) has been elucidated, but no previous meta-analysis was done to provide firm evidence. Therefore, this systematic review and meta-analysis was aimed to investigate the possible association between serum Zn levels and CAD patients.Relevant studies were identified using various electronic databases (PubMed, Scopus, Embase, Google Scholar, and Web of Science) searching up to May 2021. The Review Manager V5.3 was used to calculate the pooled standard mean difference (SMD) with the corresponding 95 % confidence interval (CI) using the random-effects model.A total of 10 studies with 614 cases (CAD patients) and 508 controls were included in this meta-analysis based on inclusion and exclusion criteria. The pooled results of the meta-analysis showed that CAD patients had significantly lower levels of Zn [SMD (95 % CI): -3.76 (-5.21, -2.31), Z = 5.08, P < 0.00001; I2= 98 %, P < 0.00001] compared with control subjects. The statistical evaluations of Begg's and Egger's tests indicated that there was no publication bias.The findings of the meta-analysis suggest that relatively low levels of Zn might have a potential role in the pathogenesis of CAD. Furthermore, large-scale observational studies are highly recommended in order to fully understand the association between Zn status and CAD.