Prospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. May 15, 2020; 11(5): 202-212
Published online May 15, 2020. doi: 10.4239/wjd.v11.i5.202
Severity of the metabolic syndrome as a predictor of prediabetes and type 2 diabetes in first degree relatives of type 2 diabetic patients: A 15-year prospective cohort study
Rokhsareh Meamar, Masoud Amini, Ashraf Aminorroaya, Maryam Nasri, Majid Abyar, Awat Feizi
Rokhsareh Meamar, Isfahan Endocrine and Metabolism Research Center, Isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
Masoud Amini, Ashraf Aminorroaya, Majid Abyar, Awat Feizi, Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
Maryam Nasri, Grovemead Health Center, London NW4-3EB, United Kingdom
Awat Feizi, Department of Biostatistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran
Author contributions: Amini M generated the idea and designed the Isfahan diabetes prevention study, participated in most of the experiments, revising the paper critically for important intellectual content; Meamar R generated the idea and designed the current secondary study, wrote all major parts of the article and checked it for intellectual content and revised it; Feizi A supervised the current secondary study and drafted the paper and revised it critically for important intellectual content and performed all statistical analyses; Aminorroaya A essentially participated as co-investigator in Isfahan diabetes prevention study, revised paper critically for important intellectual content; Nasri M edited and resolved grammatical errors in the article; Abyar M assisted in data collection and preparation and statistical analysis.
Supported by Isfahan Endocrine and Metabolism Research Center, No. 95017.
Institutional review board statement: The study was reviewed and approved by the institutional review boards of Isfahan University of Medical Sciences, Isfahan, Iran. Study project number: 95017.
Informed consent statement: All study participants, provided written consent prior to study enrollment.
Conflict-of-interest statement: The authors of this manuscript having no conflicts of interest to disclose.
Data sharing statement: There is no additional data 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: Awat Feizi, PhD, Professor, Statistician, Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, P.O. Box 319, Hezar-Jerib Ave, Isfahan 81746-73461, Iran. awat_feiz@hlth.mui.ac.ir
Received: December 16, 2019
Peer-review started: December 16, 2019
First decision: January 6, 2020
Revised: March 16, 2020
Accepted: March 23, 2020
Article in press: March 23, 2020
Published online: May 15, 2020
Abstract
BACKGROUND

Type 2 diabetes mellitus (T2DM) has high morbidity and mortality worldwide, therefore there is of paramount importance to identify the risk factors in the populations at risk early in the course of illness. A strong correlation between severity of metabolic syndrome (MetS) and HbA1c, fasting insulin and insulin resistance has been reported. Accordingly, the MetS severity score (or MestS Z-score) can potentially be used to predict the risk of T2DM progression over time.

AIM

To evaluate the association the of MestS Z-score in first degree relatives (FDRs) of T2DM with the risk of prediabetes and type 2 diabetes in future.

METHODS

A prospective open cohort study was conducted between 2003-2018. At baseline, the sample comprised of 1766 FDRs of patients with T2DM who had a normal glucose tolerance test. Relative risk (RR) and 95% confidence interval were calculated based on logistic regression. The receiver-operator characteristic analysis and area under the curve based on MetS Z-score were used to evaluate the risk of prediabetes and diabetes among the FDR population.

RESULTS

Baseline MetS Z-scores were associated with the its latest values (P < 0.0001). Compared with individuals who were T2DM free at the end of follow up, those who developed T2DM had higher MetS Z-score at baseline (P < 0.001). In multivariable logistic regression analyses for every unit elevation in MetS Z-score at the baseline, the RR for developing future T2DM and prediabetes was (RR = 1.94, RR = 3.84), (RR = 1.5, RR = 2.17) in total population and female group, respectively (P < 0.05). The associations remained significant after adjusting the potential confounding variables. A cut off value of 0.97 and 0.94 was defined in the receiver-operator characteristic curve based on the MetS Z-score for differentiating female patients with diabetes and prediabetes from the normal population, respectively.

CONCLUSION

The MetS Z-score was associated with an increased risk of future T2DM. Appropriate interventions at earlier stages for preventing and attenuating MetS effects may be considered as an effective strategy for FDR as at-risk population.

Keywords: Insulin resistance, Metabolic syndrome, Risk, Type 2 diabetes mellitus, Prediabetes, First degree relative

Core tip: This prospective cohort study showed that metabolic syndrome severity score at baseline, in first degree relative of type 2 diabetes mellitus patients with normal glucose tolerance, predicts the incidence of future diabetes and prediabetes. In this study, the cut off values of metabolic syndrome Z-score for predicting prediabetes and diabetes were 0.94 and 0.97, respectively. This negligible difference between two groups in terms of cut off values highlights the importance of intervention at prediabetes stage.