Background: This study aims to assess the correlation between maximal oxygen uptake (peakVO₂) during cardiopulmonary exercise test (CPET) and peakVO₂ obtained from incremental shuttle walking test (ISWT) in patients with chronic obstructive pulmonary disease (COPD) and to investigate their relationship with quality of life.

Methods: Data of 38 stable COPD patients (35 males, 3 females; mean age 64.6±8.3 years; range 48 to 82 years) who completed outpatient pulmonary rehabilitation (PR) program and assessed by CPET and ISWT through treadmill test was retrospectively analyzed. Pulmonary rehabilitation was performed during eight weeks. PeakVO₂ measured via breath-by-breath technique during CPET. PeakVO₂ from ISWT distance was calculated by the formula “4.19+ [0.025x ISWT distance]”. Borg scale was used for the evaluation of dyspnea severity before and after PR, whereas St. George’s Respiratory Questionnaire was used for quality of life.

Results: PeakVO₂ on CPET were found 15.9±5.1 ml/min/kg before PR and 17.3±5.3 ml/min/kg after PR (p=0.001). The peakVO₂ calculated with ISWT was 11.6±3.2 m l/min/kg before PR and 13.4±3.2 ml/min/kg after PR (p<0.001). Incremental shuttle walking test distance increased from 296.1±128.9 meters to 367.1±129.1 meters (p<0.001). A significant relationship between peakVO₂ on CPET and calculated peakVO₂ from ISWT before and after PR (p=0.001, p=0.005, respectively). A moderate positive correlation (r=0.50) and a weak correlation (r=0.449) were found before and after PR, respectively. Dyspnea was reduced and quality of life and walking distance were improved after PR. There were significant but weak correlations between activity, impact, total score of St. George’s Respiratory Questionnaire and peakVO₂ on CPET before and after PR (p<0.05).

Conclusion: Incremental shuttle walking test can also be used for the evaluation of exercise capacity in COPD patients. Although it is an inexpensive and easy-to-use method, CPET should be preferred to achieve objective results.

Keywords : Cardiopulmonary exercise test; chronic obstructive pulmonary disease; incremental shuttle walking test; maximal oxygen uptake