Meta-Analysis
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Apr 28, 2021; 9(2): 208-219
Published online Apr 28, 2021. doi: 10.13105/wjma.v9.i2.208
Helicobacter pylori infection and susceptibility to cardiac syndrome X: A systematic review and meta-analysis
Mohsen Karbalaei, Amirhossein Sahebkar, Masoud Keikha
Mohsen Karbalaei, Department of Microbiology and Virology, Faculty of Medicine, Jiroft University of Medical Sciences, Jiroft 43317803, Iran
Amirhossein Sahebkar, Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
Amirhossein Sahebkar, Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
Masoud Keikha, Department of Microbiology and Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad 9177948974, Iran
Author contributions: Keikha M and Sahebkar A equally contributed to the conception and design of the study; Karbalaei M and Keikha M conducted the literature review and analyses; All authors equally contributed to drafting and critical revision and editing of the manuscript, and approved the final version.
Conflict-of-interest statement: No potential conflicts of interest.
PRISMA 2009 Checklist statement: The manuscript was revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Masoud Keikha, PhD, Doctor, Instructor, Teaching Assistant, Department of Microbiology and Virology, Faculty of Medicine, Mashhad University of Medical Sciences, Park Square, Mashhad 9177948974, Iran. masoud.keykha90@gmail.com
Received: December 30, 2020
Peer-review started: December 30, 2020
First decision: February 28, 2021
Revised: March 3, 2021
Accepted: April 23, 2021
Article in press: April 23, 2021
Published online: April 28, 2021
Processing time: 118 Days and 19.6 Hours
Abstract
BACKGROUND

Cardiac syndrome X (CSX) is characterized by persistent angina with normal coronary arteries. Several pathophysiologic mechanisms have been introduced, particularly Helicobacter pylori (H. pylori) infection.

AIM

To investigate the association between H. pylori infection and CSX.

METHODS

All studies related to H. pylori infection and CSX were evaluated by comprehensive searches of global databases such as ISI Web of Knowledge, PubMed, Scopus, EMBASE, and Google scholar. Statistical analyses of selected articles were evaluated based on the summary odds ratio (OR). Finally, heterogeneity and publication bias were estimated using the I2 statistic and Cochrane Q-test as well as Begg’s and Egger’s tests.

RESULTS

A total of 11 studies met our inclusion criteria and 1435 patients (63% female, and 37% male) were reviewed. A significant association was observed between female patients and this syndrome (P = 0.02). Our results showed a positive association between infection with this pathogen and presence of CSX (OR: 5.65; 95% confidence interval [CI]: 4.17-7.64; I2: 82.20). However, no significant association was observed with cagA-positive H. pylori strains and this syndrome (OR: 0.97; 0.56-1.70 with 95%CI). Given the heterogeneity and publication bias, the results need to confirmed by further prospective investigation.

CONCLUSION

Based on our results, H. pylori infection is associated with an increased risk of CSX. This bacterium appears to play a major role in the pathogenesis of CXS by inducing persistent inflammation.

Keywords: Helicobacter pylori; Cardiac syndrome X; Cardiovascular disease; Infection; Meta-analysis; Coronary diseases

Core Tip: According to various studies, persistent colonization and chronic inflammation caused by Helicobacter pylori (H. pylori) infection can lead to systemic disorders outside the gastrointestinal tract. Recently, the role of H. pylori in cardiac syndrome X (CSX) has garnered attention. Nevertheless, the mechanism of this syndrome is not fully understood, and it remains controversial. Data from 11 studies were evaluated to assess the association between H. pylori infection and CSX. The results showed that there is a positive association between infection with this bacterium and the development of CSX. It seems that H. pylori increase the risk of CSX through dysregulation of the immune response and alternating epigenetic events. Statistical analyses showed that the presence of CSX was not dependent on cagA status. Several limitations such as small sample size, heterogeneity, and publication bias indicate that confirmation of the present results by further prospective investigation is necessary.