Liao LZ, Chen ZC, Li WD, Zhuang XD, Liao XX. Causal effect of education on type 2 diabetes: A network Mendelian randomization study. World J Diabetes 2021; 12(3): 261-277 [PMID: 33758646 DOI: 10.4239/wjd.v12.i3.261]
Corresponding Author of This Article
Xin-Xue Liao, PhD, Chief Physician, Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Yuexiu District, Guangzhou 510080, Guangdong Province, China. liaoxinx@mail.sysu.edu.cn
Research Domain of This Article
Genetics & Heredity
Article-Type of This Article
Basic Study
Open-Access Policy of This Article
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: http://creativecommons.org/licenses/by-nc/4.0/
Li-Zhen Liao, Wei-Dong Li, Department ofHealth, Guangdong Pharmaceutical University, Guangzhou 510275, Guangdong Province, China
Li-Zhen Liao, Wei-Dong Li, Guangdong Provincial Key Laboratory of Pharmaceutical Bioactive Substances, Guangdong Pharmaceutical University, Guangzhou 510006, Guangdong Province, China
Zhi-Chong Chen, Department of Cardiology, The Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, Guangdong Province, China
Xiao-Dong Zhuang, Xin-Xue Liao, Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, Guangdong Province, China
Author contributions: Liao LZ and Chen ZC conceived the study and contributed equally to this study; Li WD completed the analyses; Zhuang XD led the writing; Liao XX supervised the study.
Supported bythe National Natural Science Foundation of China, No. 81701378.
Institutional review board statement: Not applicable.
Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose.
Data sharing statement: No additional data are available.
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: Xin-Xue Liao, PhD, Chief Physician, Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan 2nd Road, Yuexiu District, Guangzhou 510080, Guangdong Province, China. liaoxinx@mail.sysu.edu.cn
Received: July 27, 2020 Peer-review started: July 27, 2020 First decision: November 4, 2020 Revised: November 10, 2020 Accepted: December 23, 2020 Article in press: December 23, 2020 Published online: March 15, 2021
Abstract
BACKGROUND
The causality between education and type 2 diabetes (T2DM) remains unclear.
AIM
To identify the causality between education and T2DM and the potential metabolic risk factors [coronary heart disease (CHD), total cholesterol, low-density lipoprotein, triglycerides (TG), body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), fasting insulin, fasting glucose, and glycated hemoglobin] from summarized genome-wide association study (GWAS) data used a network Mendelian randomization (MR).
METHODS
Two-sample MR and network MR were performed to obtain the causality between education-T2DM, education-mediator, and mediator-T2DM. Summary statistics from the Social Science Genetic Association Consortium (discovery data) and Neale Lab consortium (replication data) were used for education and DIAGRAMplusMetabochip for T2DM.
RESULTS
The odds ratio for T2DM was 0.392 (95%CI: 0.263-0.583) per standard deviation increase (3.6 years) in education by the inverse variance weighted method, without heterogeneity or horizontal pleiotropy. Education was genetically associated with CHD, TG, BMI, WC, and WHR in the discovery phase, yet only the results for CHD, BMI, and WC were replicated in the replication data. Moreover, BMI was genetically associated with T2DM.
CONCLUSION
Short education was found to be associated with an increased T2DM risk. BMI might serve as a potential mediator between them.
Core Tip: Genetically predicted education was negatively causally associated with type 2 diabetes (T2DM). The odds ratio for T2DM was 0.392 (95%CI: 0.263-0.583) per standard deviation increase (3.6 years) in education. Body mass index might serve as a potential mediator.
