Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test

Central Illustration
: Prediction of Peak Oxygen Consumption in Patients with Heart Disease Based on Performance on the Timed Up and Go Test

Abstract

Background

The use of the timed up and go (TUG) test to assess cardiorespiratory fitness in patients with heart disease has not been well defined in the literature.

Objectives

Test the association between TUG and peak oxygen consumption (VO₂peak), construct an equation based on TUG to predict VO₂peak, and determine a cutoff point to estimate VO₂peak ≥ 20 mL/kg/min.

Methods

This cross-sectional study included 201 patients with coronary artery disease or heart failure, between 36 and 92 years of age, who underwent TUG and cardiopulmonary exercise test. Correlation, ROC curve, multiple linear regression, and Bland-Altman analyses were performed. The significance level was set at p < 0.05.

Results

The mean age of the total sample was 67 ± 13 years, and 70% of participants were male. The mean VO₂peak was 17 ± 6 mL/kg/min, and the mean TUG time was 7 ± 2.5 seconds. The correlation between VO₂peak and TUG was r = −0.54 (p < 0.001), and R² was 0.30. The following equation was developed based on $\text{TUG:}{VO}_2\text{peak}=33.553+(-0.149\times \text{age})+(-0.738\times \text{TUG})+(-2.870\times \text{sex})$; a value of 0 was assigned to the male sex and 1 to the female sex (adjusted R: 0.41; adjusted R²: 0.40). The VO₂peak estimated by the equation was 18.81 ± 3.2 mL/kg/min, and the VO₂peak determined by cardiopulmonary exercise test was 18.18 ± 5.9 mL/kg/min (p > 0.05). The best cutoff point in the TUG for VO₂peak ≥ 20 mL/kg/min was ≤ 5.47 seconds (area under the curve: 0.80; 95% confidence interval: 0.74 to 0.86).

Conclusions

TUG and VO₂peak showed a significant association. A prediction equation for VO₂peak was developed and validated internally with good performance. The cutoff point in the TUG to predict VO₂peak ≥ 20 mL/kg/min was ≤ 5.47 seconds.

Oxygen Consumption; Cardiovascular Diseases; Exercise Test