Case Control Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Feb 15, 2021; 12(2): 138-148
Published online Feb 15, 2021. doi: 10.4239/wjd.v12.i2.138
Plasma melatonin levels in patients with diabetic retinopathy secondary to type 2 diabetes
Wen-Cui Wan, Yang Long, Wei-Wei Wan, Hong-Zhuo Liu, Hao-Hao Zhang, Wei Zhu
Wen-Cui Wan, Yang Long, Wei-Wei Wan, Hong-Zhuo Liu, Wei Zhu, Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
Hao-Hao Zhang, Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan Province, China
Wei Zhu, Department of Ophthalmology, Changshu No. 2 People's Hospital, Changshu 215000, Jiangsu Province, China
Author contributions: Wan W,Long Y and Zhang HH contributed equally to this work; Wan W, Long Y, Wan W, Liu H, Zhang H and Zhu W designed the research study; Wan W, Long Y, Wan W, Liu H and Zhang H performed the research; Wan W, Long Y, Wan W and Zhu W contributed new reagents and analytic tools; Wan W, Long Y and Wan W analyzed the data and wrote the manuscript; all authors have read and approved the final manuscript.
Supported by National Nature Science Foundation Project for Young Scientists of China, No. 81700804; The Foundation for Young Medical Talents of Jiangsu Province, No. QNRC2016211; Scientific Research Project of Jiangsu Health Commission, No. Z2019044; and Youth Project of Henan Provincial Health and Health Commission, Ministry of Education, No. SB201902008.
Institutional review board statement: The study was reviewed and approved by the Ethical Committee of the Changshu No. 2 People’s Hospital (Approval No. 2020-KY-003).
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors report no conflicts of interest.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
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: Wei Zhu, MD, Attending Physician, Department of Ophthalmology, Changshu No. 2 People's Hospital, No. 99 Xiannan Street, Changshu 215000, Jiangsu Province, China. shzhuwei0722@163.com
Received: August 2, 2020
Peer-review started: August 2, 2020
First decision: November 18, 2020
Revised: November 26, 2020
Accepted: December 10, 2020
Article in press: December 10, 2020
Published online: February 15, 2021
Processing time: 174 Days and 1.4 Hours
Core Tip

Core Tip: Melatonin is reported to be related to diabetes mellitus risk; however, the effect of melatonin on diabetic retinopathy (DR) risk remains unclear. The data obtained in this study demonstrated that plasma melatonin concentration was decreased in DR cases and could be used as a sensitive and specific marker for the diagnosis of DR. A significant positive relationship between total bilirubin and melatonin was detected. More related studies are required to understand the role of melatonin in DR.