Introduction: High cardiorespiratory fitness (CRF) is strongly associated with longer life among older adults. CRF can be assessed by exercise-based methods, which are not feasible in most clinical settings. Thus, non-exercise algorithms to estimate CRF have been developed, but whether they predict mortality in older adults is uncertain.
Methods: A cohort of 1470 men and 1460 women, representative of the Spanish population aged >=60 years, was established in 2000/2001 and followed-up prospectively through 2011. At baseline, non-exercise CRF was estimated with the sex-specific algorithms developed by Jackson et al. Analyses were performed with Cox regression and adjusted for the main confounders.
Results: During an average follow-up of 9.4-years, 570 (38.8%) deaths occurred in men, and 295 (20.2%) in women. Among men, no association was observed between non-exercise CRF and all-cause mortality. Compared to women in the lowest quartile of CRF, the hazard ratio (95% confidence interval) for all cause-death was 0.81 (0.62-1.06) in the second quartile, 0.68 (0.48-0.95) in the third quartile, and 0.56 (0.36-0.87) in the highest quartile (P for trend=0.004). Results held regardless of age, body mass index, waist circumference, heart rate, subjective health, functional limitations, and disease status.
Conclusions: Higher non-exercise CRF was related to lower risk of death in older women but not in men. Since previous research does not support a clear sex-specific association, further research is required to assess if non-exercise CRF predicts mortality in older adults or new algorithms should be developed for this population with special attention to older men.
(C) 2014 American College of Sports Medicine