The research reported in this article was supported by contract numbers N01-HC-85079 through N01-HC-85086, N01-HC-35129, N01 HC-15103, N01 HC-55222, N01-HC-75150, N01-HC-45133, grant number U01 HL080295 from the National Heart, Lung, and Blood Institute, with additional contribution from the National Institute of Neurological Disorders and Stroke. A full list of principal CHS investigators and institutions can be found at http://www.chs-nhlbi.org/pi.htm. In addition this research was supported by R0–1 HL62181 from the National Heart, Lung, and Blood Institute.
Relationship of Abnormal Heart Rate Turbulence and Elevated CRP to Cardiac Mortality in Low, Intermediate, and High-Risk Older Adults
Article first published online: 6 DEC 2010
© 2010 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 22, Issue 2, pages 122–127, February 2011
How to Cite
STEIN, P. K. and BARZILAY, J. I. (2011), Relationship of Abnormal Heart Rate Turbulence and Elevated CRP to Cardiac Mortality in Low, Intermediate, and High-Risk Older Adults. Journal of Cardiovascular Electrophysiology, 22: 122–127. doi: 10.1111/j.1540-8167.2010.01967.x
Work performed at Washington University School of Medicine.
- Issue published online: 11 FEB 2011
- Article first published online: 6 DEC 2010
- Manuscript received 25 May 2010; Revised manuscript received 14 October 2010; Accepted for publication 18 October 2010.
- autonomic nervous system;
- ambulatory ECG;
- cardiac mortality;
- C-reactive protein;
- heart rate turbulence
HRT and CRP for Mortality Risk in Elderly. Introduction: We examined whether heart rate turbulence (HRT) and C-reactive protein (CRP) add to traditional risk factors for cardiac mortality in older adults at low, intermediate, and high risk.
Methods and Results: One thousand two hundred and seventy-two individuals, age ≥65 years, with 24-hour Holter recordings were studied. HRT, which quantifies heart rate response to ventricular premature contractions, was categorized as: both turbulence onset (TO) and turbulence slope (TS) normal; TO abnormal; TS abnormal; or both abnormal. Independent risks for cardiac mortality associated with HRT or, for comparison, elevated CRP (>3.0 mg/L), were calculated using Cox regression analysis adjusted for traditional cardiovascular disease risk factors and stratified by the presence of no, isolated subclinical (i.e., intermediate risk) or clinical cardiovascular disease. Having TS + TO abnormal compared to both normal was associated with cardiac mortality in the low-risk group [HR 7.9, 95% confidence interval (CI) 2.8–22.5, (P < 0.001)]. In the high and intermediate risk groups, abnormal TS and TS + TO ([HR 2.2, 95% CI 1.5–4.0, P = 0.016] and [HR 2.7, 95% CI 1.2–5.9, P = 0.012]), respectively, were also significantly associated with cardiac mortality. In contrast, elevated CRP was associated with increased cardiac mortality risk only in low-risk individuals [HR 2.5, 95% CI 1.3–5.1, P = 0.009]. Among low risk, the c-statistic was 0.706 for the base model, 0.725 for the base model with CRP, and 0.767 for the base model with HRT.
Conclusions: Abnormal HRT independently adds to risk stratification of low, intermediate and high-risk individuals, but HRT and CRP appear to both add to stratification of those considered low risk. (J Cardiovasc Electrophysiol, Vol. 22, pp. 122-127, February 2011)