PALO ALTO, CA — Cardiorespiratory fitness (CRF) is inversely associated with cardiovascular and all-cause mortality. A new study published in the journal Circulation: Heart Failure, took that a step further, however, to determine whether CRF also is associated with lower incidence of heart failure (HF).1
To do that, researchers from the VA Palo Alto, CA, Healthcare System and Stanford University researchers assessed CRF in 21,080 HF-free subjects, average age 58.3, at VAMCs in Washington, DC, and Palo Alto, CA, between 1987 and 2014.
Participants were classified by age-specific quintiles of CRF, while analysis was used determine the association between HF incidence and clinical and exercise test variables.
Results indicated that, during the follow-up after an average of 12.3 years, 1,902 subjects, 9%, developed HF for an average annual incidence rate, 7.4 events per 1000 person-years. When CRF was considered as a binary variable – unfit vs. fit – low fitness was the strongest predictor of risk for HF among clinical and exercise test variables, for a hazard ratio of 1.91.
When the model was fully adjusted with the least-fit group as the reference, graded and progressive reduction in risk for HF was demonstrated as fitness level increased.
Risks for developing HF were 36%, 41%, 67%, and 76% lower among increasing quintiles of fitness compared with the least-fit subjects. Adding CRF to standard risk factors resulted in a net reclassification improvement of 0.37.
“CRF is strongly, inversely, and independently associated with the incidence of HF in veterans referred for exercise testing,” researchers concluded.
- Khan H, Jaffar N, Rauramaa R, Kurla S, Savona K, Alkanes JA.
Cardiorespiratory fitness and nonfatal cardiovascular events: A population-based follow-up study. Am Heart J. 2017 Feb;184:55-61. do: 10.1016/j.ahj.2016.10.019.