Abstract 12993: The Association of Resting Heart Rate and Incident Hypertension: The Henry Ford HospITal Exercise Testing (FIT) Project
OBJECTIVE: While high resting heart rate (RHR) is associated with cardiovascular disease (CVD), the mechanism is unclear. Given that sympathetic tone is associated with prevalent hypertension (HTN), we sought to determine whether RHR, as a surrogate for cardiac autonomic function, was associated with incident HTN.
METHODS: We analyzed 22,187 individuals without a history of HTN who underwent a clinically indicated exercise stress test between January 1991 and May 2009. Baseline RHR was categorized as <70, 70-85 and >85 beats-per-minute (bpm). Seated RHR was assessed before each stress test. Incident HTN was defined by coding for new onset HTN on claims files on three or more subsequent encounters. Adjusted Cox models were used to study the association of RHR and incident HTN. We tested for effect modification by age and gender.
RESULTS: Mean age was 49 years (SD 12), 55% were men and 21% were black. 90% of patients achieved ≤ 85% of predicted maximal HR during the stress test. Compared to the lowest RHR (<70 bpm) category, patients in the highest category (>85 bpm) were more likely to be younger, female, heavier, non-smokers, diabetic, and have a family history of CVD (p<0.05). They had lower peak metabolic equivalents (METS) and a higher percentage of predicted maximum HR (p<0.05). Over a median of 4 years follow up, there were 8,329 cases of incident HTN. RHR >85 bpm was independently associated with risk for incident HTN after adjustment for demographics, cardiac risk factors and peak METS [Hazard ratios= 1.22 (95% CI 1.12-1.32), compared to RHR <70 (TABLE)]. Age, but not gender, was an effect-modifier (p for interaction 0.008). In age stratified analyses the relationship remained significant only in <60 year olds (TABLE).
CONCLUSION: Elevated RHR is an independent risk factor for incident HTN, particularly in persons < 60 years. Whether lifestyle modification or other strategies to reduce RHR can prevent incident HTN in individuals at risk for HTN warrants further study.
Author Disclosures: A.I. Aladin: None. M. Al Rifai: None. S.H. Rasool: None. S.J. Keteyian: None. C.A. Brawner: None. E.D. Michos: None. M.J. Blaha: None. M. Al-Mallah: None. J.W. McEvoy: None.
- © 2014 by American Heart Association, Inc.