Inflammatory biomarkers in cardiac syndrome X: a systematic review and meta-analysis.

INTRODUCTION

In the current systematic review and meta-analysis, we aim to analyze the existing literature to evaluate the role of inflammatory biomarkers, including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP), tumor necrosis factor-a (TNF-a), and interleukin-6 (IL-6) among individuals with cardiac syndrome X (CSX) compared to healthy controls.

METHODS

We used PubMed, Web of Science, Scopus, Science Direct, and Embase to systematically search relevant publications published before April 2, 2023. We performed the meta-analysis using Stata 11.2 software (Stata Corp, College Station, TX). So, we used standardized mean difference (SMD) with a 95% confidence interval (CI) to compare the biomarker level between patients and healthy controls. The I2 and Cochran's Q tests were adopted to determine the heterogeneity of the included studies.

RESULTS

Overall, 29 articles with 3480 participants (1855 with CSX and 1625 healthy controls) were included in the analysis. There was a significantly higher level of NLR (SMD = 0.85, 95%CI = 0.55-1.15, I2 = 89.0 %), CRP (SMD = 0.69, 95%CI = 0.38 to 1.02, p < 0.0001), IL-6 (SMD = 5.70, 95%CI = 1.91 to 9.50, p = 0.003), TNF-a (SMD = 3.78, 95%CI = 0.63 to 6.92, p = 0.019), and PLR (SMD = 1.38, 95%CI = 0.50 to 2.28, p = 0.02) in the CSX group in comparison with healthy controls.

CONCLUSION

The results of this study showed that CSX leads to a significant increase in inflammatory biomarkers, including NLR, CRP, IL-6, TNF-a, and PLR.