Meta-Analysis
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Jun 15, 2021; 12(6): 908-915
Published online Jun 15, 2021. doi: 10.4239/wjd.v12.i6.908
Coffee consumption and risk of type 2 diabetes mellitus in Asians: A meta-epidemiological study of population-based cohort studies
Jong-Myon Bae
Jong-Myon Bae, Department of Preventive Medicine, Jeju National University School of Medicine, Jeju-si 63243, South Korea
Author contributions: Bae JM designed the research study, performed the research; analyzed the data and wrote the manuscript.
Conflict-of-interest statement: The author declares no conflict of interests and no funding sources for this article.
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 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: Jong-Myon Bae, MD, PhD, Professor, Department of Preventive Medicine, Jeju National University School of Medicine, 102 Jejudaehak-ro, Jeju-si 63243, South Korea. jmbae@jejunu.ac.kr
Received: November 27, 2020
Peer-review started: November 27, 2020
First decision: December 20, 2020
Revised: December 23, 2020
Accepted: May 19, 2021
Article in press: May 19, 2021
Published online: June 15, 2021
Processing time: 188 Days and 14.4 Hours
Abstract
BACKGROUND

Previous systematic reviews have consistently reported that coffee consumption has a preventive effect on the occurrence of type 2 diabetes mellitus (T2DM). However, further evaluations between coffee consumption and the risk of T2DM in Asian populations are needed.

AIM

To conduct a meta-epidemiological study on systematic reviews evaluating the association between coffee consumption and the risk of T2DM in Asian people.

METHODS

The selection criterion was defined as a population-based prospective cohort study evaluating the association between coffee consumption and the risk of T2DM in Asian populations, reporting the adjusted relative risk (RR) and its 95% confidence interval (CI) for potential confounders. A fixed-effect model meta-analysis was applied to calculate the summary RR and its 95%CI in less than 50% of the I2 value indicating the level of heterogeneity. A two-stage fixed-effects dose-response meta-analysis (DRMA) was performed to calculate the risk per unit dose (a cup per day).

RESULTS

A total of seven studies were selected in this meta-epidemiological study. The risk of T2DM in Asian populations was significantly reduced in the highest to the lowest dose group (summary RR = 0.73, 95%CI: 0.66-0.82; I2 value = 0.0%). The DRMA showed that drinking one cup of coffee per day reduced the risk of T2DM in Asian populations by 8% (RR = 0.92, 95%CI: 0.90-0.95).

CONCLUSION

These findings support the conclusion that coffee consumption has a protective effect on the occurrence of T2DM in Asian men and women.

Keywords: Coffee; Diabetes mellitus; Cohort studies; Meta-analysis; Systematic reviews

Core Tip: Previous systematic reviews have consistently reported that coffee consumption has a preventive effect on the occurrence of type 2 diabetes mellitus (T2DM). However, differences in coffee consumption habits by region could create heterogeneity. This research aimed to conduct a meta-epidemiological study on systematic reviews evaluating the association between coffee consumption and the risk of T2DM in Asian populations. From a total of seven Asian cohort studies, it was concluded that coffee consumption has a protective effect on the occurrence of T2DM in Asian men and women.