title: Heart rate at rest, exercise capacity, and mortality risk in veterans.
abstract: Heart rate (HR) at rest has been associated inversely with mortality risk. However, fitness is inversely associated with mortality risk and both increased fitness and β-blockade therapy affect HR at rest. Thus, both fitness and β-blockade therapy should be considered when HR at rest-mortality risk association is assessed. From 1986 to 2011, we assessed HR at rest, fitness, and mortality in 18,462 veterans (mean age = 58 ± 11 years) undergoing a stress test. During a median follow-up period of 10 years (211,398 person-years), 5,100 died, at an average annual mortality of 24.1 events/1,000 person-years. After adjusting for age, body mass index, cardiac risk factors, medication, and exercise capacity, we noted approximately 11% increase in risk for each 10 heart beats. To assess the risk in a wide and clinically relevant spectrum, we established 6 HR at rest categories per 10 heart beat intervals ranging from <60 to ≥100 beats. Mortality risk was significantly elevated at a HR at rest of ≥70 beats/min (hazard ratio 1.14, confidence interval 1.04 to 1.25; p <0.006) and increased progressively to 49% (hazard ratio 1.49, confidence interval 1.29 to 1.73; p <0.001) for those with a HR at rest of ≥100 beats/min. Similar trends were noted when for subjects aged <60 and ≥60 years and those treated with β blockers. In all assessments, mortality risk was consistently overestimated when fitness was not considered. In conclusion, HR at rest-mortality risk association was direct and independent. A progressive increase in risk was noted >70 beats/min for the entire cohort, those treated with β blockers, and those aged <60 and ≥60 years. Mortality risk was overestimated slightly when fitness status was not considered.
authors.affiliation: Department of Medicine, Veterans Affairs Medical Center, Washington, DC; Department of Medicine, George Washington University School of Medicine, Washington, DC.
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Pittaras
authors.forename: Charles
authors.initials: C
authors.lastname: Faselis
authors.forename: Michael
authors.initials: M
authors.lastname: Doumas
authors.forename: Jonathan
authors.initials: J
authors.lastname: Myers
authors.forename: Raya
authors.initials: R
authors.lastname: Kheirbek
authors.forename: John Peter
authors.initials: JP
authors.lastname: Kokkinos
authors.forename: Apostolos
authors.initials: A
authors.lastname: Tsimploulis
authors.forename: Monica
authors.initials: M
authors.lastname: Aiken
authors.forename: Peter
authors.initials: P
authors.lastname: Kokkinos
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality* / Q000503:physiopathology; D016001:Confidence Intervals; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012146:Rest / Q000502:physiology*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014728:Veterans