Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jun 26, 2019; 7(12): 1444-1455
Published online Jun 26, 2019. doi: 10.12998/wjcc.v7.i12.1444
Relationship between circulating irisin levels and overweight/obesity: A meta-analysis
Jue Jia, Fan Yu, Wei-Ping Wei, Ping Yang, Ren Zhang, Yue Sheng, Yong-Qin Shi
Jue Jia, Fan Yu, Wei-Ping Wei, Ping Yang, Yue Sheng, Yong-Qin Shi, Affiliated Hospital of Jiangsu University, Zhenjiang 212001, Jiangsu Province, China
Ren Zhang, Department of Library of Jiangsu University, Zhenjiang 212001, Jiangsu Province, China
Author contributions: Jia J conceived and designed the study; Jia J, Yu F, and Zhang R searched the related articles; Yang P, Wei WP, Sheng Y, and Shi YQ analyzed the data; Jia J and Yu F wrote the manuscript; all authors read and approved the final manuscript.
Supported by the National Natural Science Foundation of China, No. 81500351; the Youth Medical Talent Project of Jiangsu Province, No. QNRC2016842; the Jiangsu University Affiliated Hospital "; 5123"; Talent Plan, No. 51232017305; and the 169 Talent Project of Zhenjiang.
Conflict-of-interest statement: The authors deny any conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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:
Corresponding author: Jue Jia, MD, Lecturer, Associate Chief Physician, Affiliated Hospital of Jiangsu University, No. 438, Jiefang North Road, Jingkou District, Zhenjiang 212001, Jiangsu Province, China.
Telephone: +86-511-85031120 Fax: +86-511-85019237
Received: February 25, 2019
Peer-review started: February 26, 2019
First decision: April 18, 2019
Revised: April 27, 2019
Accepted: May 2, 2019
Article in press: May 2, 2019
Published online: June 26, 2019
Research background

Overweight/obesity has been a global health challenge and irisin as a novel myokine is reported to play an important role in the development of metabolism dysfunction and obesity, however, the exact relationship between irisin and overweight/obesity remains unclear.

Research motivation

Many studies on the results of circulating irisin levels in overweight/obesity people are incon-sistent, which has puzzled us in confirming the role of irisin in overweight/obesity, thus, it is necessary to do such an analysis to clarify the relationship between them.

Research objectives

The main objective was to extract available data from studies and clarify the relationship between irisin and overweight/obesity.

Research methods

We searched Cochrane Library, MEDLINE, SCOPUS, and the ISI Web of Science to retrieve all of the studies associated with circulating irisin levels and overweight/obesity. We estimated standard mean difference values and 95% confidence intervals and used meta-analysis methodology to get final results.

Research results

A total of 18 studies were included in this meta-analysis containing 1005 cases and 1242 controls. The overall analysis showed that the circulating irisin level in overweight/obese people was higher than that in overall healthy controls. In the subgroup analysis by ethnicity, the irisin level was higher in overweight/obese people than that in controls in Africa. In addition, in a subgroup analysis by age, the results showed that obese children exhibited a higher irisin level than controls. Studies of larger population samples are needed to better explore the relationship between irisin and overweight/obesity.

Research conclusions

This study integrated the existing data to show that the circulating irisin levels in over-weight/obese people was higher than those in healthy controls overall, and explored the potential of irisin as a predictive factor for overweight/obesity.

Research perspectives

More studies on the effects of exercise, lifestyle, and weight loss on the irisin level and related prospective studies are needed.