Observational Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Diabetes. Jan 15, 2018; 9(1): 33-39
Published online Jan 15, 2018. doi: 10.4239/wjd.v9.i1.33
Heart rate is an independent predictor of all-cause mortality in individuals with type 2 diabetes: The diabetes heart study
Sameer Prasada, Cameron Oswalt, Phyllis Yeboah, Georgia Saylor, Donald Bowden, Joseph Yeboah
Sameer Prasada, Cameron Oswalt, Department of Medical School (Medical students), Wake Forest University, Winston Salem, NC 27157, United States
Phyllis Yeboah, Department of Internal Medicine, Wake Forest Baptist Health, Winston Salem, NC 27157, United States
Georgia Saylor, Joseph Yeboah, Department of Heart and Vascular Center of Excellence, Wake Forest Baptist Health, Winston Salem, NC 27157, United States
Donald Bowden, Department of Biochemistry, Genomics and Personalized Medicine Research, Wake Forest University, Winston Salem, NC 27157, United States
Author contributions: Bowden D enrolled subjects and collected data for the Diabetes Heart Study; Prasada S and Yeboah J designed the study and performed statistical analysis using Statistical Analysis System JMP; Prasada S and Oswalt C wrote the manuscript; Yeboah P and Yeboah J helped write and edit the manuscript; all authors contributed to this article.
Institutional review board statement: The Diabetes Heart Study was approved by the Wake Forest University Institutional Review Board.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment in the Diabetes Heart Study (DHS).
Conflict-of-interest statement: No potential conflicts of interest relevant to this article were reported.
Data sharing statement: No additional data are available.
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: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Joseph Yeboah, MD, MS, Department of Heart and Vascular Center of Excellence, Wake Forest Baptist Health, Medical Center Blvd, Winston Salem, NC 27157, United States. jyeboah@wakehealth.edu
Telephone: +1-336-7167015 Fax: +1-336-7169188
Received: May 4, 2017
Peer-review started: May 5, 2017
First decision: July 20, 2017
Revised: July 25, 2017
Accepted: November 25, 2017
Article in press: November 25, 2017
Published online: January 15, 2018
Abstract
AIM

To assess the association of resting heart rate with all-cause and cardiovascular disease (CVD) mortality in the Diabetes Heart Study (DHS).

METHODS

Out of a total of 1443 participants recruited into the DHS, 1315 participants with type 2 diabetes who were free of atrial fibrillation and supraventricular tachycardia during the baseline exam were included in this analysis. Heart rate was collected from baseline resting electrocardiogram and mortality (all-cause and CVD) was obtained from state and national death registry. Kaplan-Meier (K-M) and Cox proportional hazard analyses were used to assess the association.

RESULTS

The mean age, body mass index (BMI) and systolic blood pressure (SBP) of the cohort were 61.4 ± 9.2 years, 32.0 ± 6.6 kg/m2, and 139.4 ± 19.4 mmHg respectively. Fifty-six percent were females, 85% were whites, 15% were blacks, 18% were smokers. The mean ± SD heart rate was 69.8 (11.9) beats per minute (bpm). After a median follow-up time of 8.5 years (maximum follow-up time is 14.0 years), 258 participants were deceased. In K-M analysis, participants with heart rate above the median had a significantly higher event rate compared with those below the median (log-rank P = 0.0223). A one standard deviation increase in heart rate was associated with all-cause mortality in unadjusted (hazard ratio 1.16, 95%CI: 1.03-1.31) and adjusted (hazard ratio 1.20, 95%CI: 1.05-1.37) models. Similar results were obtained with CVD mortality as the outcome of interest.

CONCLUSION

Heart rate is an independent predictor of all-cause mortality in this population with type 2 diabetes. In this study, a 1-SD increase in heart rate was associated with a 20% increase in risk suggesting that additional prognostic information may be gleaned from this ubiquitously collected vital sign.

Keywords: Diabetes mellitus, Mortality, Resting heart rate, Prevention

Core tip: Persons with type 2 diabetes mellitus (T2DM) have a higher rate of morbidity and mortality compared with those without diabetes. Prevention is the best way of reducing the risk in this population. Unlike the general population, the predictive value of resting heart rate for mortality in persons with T2DM is not well established. We used baseline data and a median of 8.5 years of follow up from the Diabetes Heart Study to show that resting heart rate is an independent predictor of mortality in individuals with T2DM. Our data suggests that efforts that reduce heart rate in T2DM may be useful.