Determining the best percent-predicted equation for estimated VO2 peak by a 1-km moderate perceptually-regulated treadmill walk to predict mortality in outpatients with cardiovascular disease

作者：Grazzi Giovanni^*; Mazzoni Gianni; Myers Jonathan; Codeca Luciano; Pasanisi Giovanni; Mandini Simona; Piepoli Massimo; Volpato Stefano; Conconi Francesco; Chiaranda Giorgio

来源：Journal of Science and Medicine in Sport, 2018, 21(3): 307-311.

DOI：10.1016/j.jsams.2017.06.003

• Exercise test
• Oxygen consumption
• Predictive value of tests
• Secondary prevention

Objectives: To determine the prognostic ability of established percent-predicted equations of peak oxygen consumption (%PRED) estimated by a moderate submaximal walking test in a large cohort of outpatients with cardiovascular disease (CVD).
Design: Population-based prospective study.
Methods: A total of 1442 male patients aged 25-85 years at baseline, underwent a moderate perceptually regulated (11-13 on the 6-20 Borg scale) treadmill walk (1 k-TWT) for peak oxygen consumption estimation (VO2 peak). %PRED was derived from ACSM, Ades et al, Morris et al, and the Wasserman/Hansen equations, and their prognostic performance was assessed. Overall mortality was the end point. Participants were divided into quartiles of %PRED, and mortality risk was estimated using a Cox regression model.
Results: During a median 8.2 year follow-up, 167 all-cause deaths occurred. The Wasserman/Hansen equation provided the highest prognostic value. Mortality rate was lower across increasing quartiles of %PRED. Compared to the first quartile, after adjustment for confounders, the mortality risk decreased for the second, third, and fourth quartiles, with HRs of 0.75 (95% CI 0.44-1.29, p = 0.29), 0.67 (95% CI 0.38-1.18, p = 0.17), and 0.37 (95% CI 0.10-0.78, p = 0.009), respectively (p for trend <0.0001). Each 1% increase in %PRED conferred a 4% improvement in survival.
Conclusions: The percent-predicted VO2 peak determined by Wasserman/Hansen equations applied to the 1k-TWT is inversely and significantly related to survival in cardiac outpatients. The 1k-TWT is a simple and useful tool for stratifying mortality risk in patients participating in secondary prevention programs.

• 出版日期2018-3