Heart rate response to a timed walk and cardiovascular outcomes in older adults: the cardiovascular health study.
OBJECTIVE
To determine the relationship between heart rate response during low-grade physical exertion (6-min walk) with mortality and adverse cardiovascular outcomes in the elderly.


METHODS
Participants in the Cardiovascular Health Study who completed a 6-min walk test were included. We used delta heart rate (difference between postwalk heart rate and resting heart rate) as a measure of chronotropic response and examined its association with (1) all-cause mortality and (2) incident coronary heart disease event, using multivariable Cox regression models.


RESULTS
We included 2,224 participants (mean age 77 ± 4 years; 60% women; 85% white). The average delta heart rate was 26 beats/min. Participants in the lowest tertile of delta heart rate (<20 beats/min) had higher risk-adjusted mortality [hazard ratio (HR) 1.18, 95% confidence interval (CI) 1.00-1.40] and incident coronary heart disease (HR 1.37, 95% CI 1.05-1.78) compared to subjects in the highest tertile (≥30 beats/min), with a significant linear trend across tertiles (p for trend <0.05 for both outcomes). This relationship was not significant after adjustment for distance walked.


CONCLUSIONS
Impaired chronotropic response during a 6-min walk test was associated with an increased risk of mortality and incident coronary heart disease among the elderly. This association was attenuated after adjusting for distance walked.
Division of Cardiovascular Diseases, Department of Internal Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA. saket-girotra@uiowa.edu
Saket
S
Girotra
Dalane W
DW
Kitzman
Willem J
WJ
Kop
Phyllis K
PK
Stein
John S
JS
Gottdiener
Kenneth J
KJ
Mukamal
D000368:Aged; D002423:Cause of Death; D003327:Coronary Disease / Q000401:mortality / Q000503:physiopathology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D016138:Walking / Q000502:physiology*