Abstract 12611: The Relationship between Resting Heart Rate and Incidence and Progression of Coronary Artery Calcification: The Multi-Ethnic Study of Atherosclerosis
Background: A: Resting heart rate (HR) has been associated with increased risk of cardiovascular morbidity and mortality. Whether heart rate is associated with more rapid progression of subclinical coronary atherosclerosis is unclear. Hypothesis: Individuals with elevated baseline resting HR will have a greater incidence and progression of CAC, compared to individuals with lower HR.
Methods: The Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective cohort study of 6,814 participants free of clinical cardiovascular disease at entry who underwent serial risk factor assessment and CAC testing. Baseline HR was categorized as continuous (per SD increase), quartiles and pre-specified cutoffs (<60 bpm, 61–70 bpm, 71–80 bpm, >80 bpm). The independent relation between increasing HR with CAC incidence was assessed by relative risk (RR) regression using a generalized linear model and binomial error distribution adjusting for covariates. Among those with detectable CAC at baseline, progression of CAC (absolute change in CAC score) was assessed with multivariable median linear regression. We excluded 767 individuals who did not undergo follow-up CAC testing and 43 individuals without information on baseline HR, for a final study population of 6,004 individuals (62±10 years, 48% males).
Results: The mean baseline resting HR was 63±10 bpm and follow-up was 3.1±1.3 years. Among 3,079 (51%) individuals with no detectable CAC at baseline, 20% (n=620) developed CAC. Table below demonstrates that in demographic and traditional risk factor adjusted analyses; increasing HR levels were associated with incident CAC. On the other hand, progression of CAC scores was only observed among those with HR>80 bpm, whereas no such relationship was noted with continuous or quartiles of HR.
Conclusions: Among individuals free of cardiovascular disease at baseline, markedly elevated resting HR is associated with both increased incidence and progression of coronary atherosclerosis.
- © 2010 by American Heart Association, Inc.