The Correlational Study Of The Oxygen Uptake Efficiency With The Exercise Capacity In Patients With Stable Chronic Obstructive Pulmonary Disease

[Objective] To explore the characteristics of the oxygen uptakeefficiency (OUE) in patients with chronic obstructive pulmonary disease(COPD), and analyze the relationship between OUE and the severity of theairway obstruction and exercise tolerance.[Methods] Pulmonary Function Test (PFT) and Cardiopulmonaryexercise testing（CPET）were tested in fifty-nine patients with stable COPDpatients (grade Ⅰ:15cases; grade Ⅱ:16cases; grade Ⅲ:19cases; grade Ⅳ:9cases) and29healthy volunteers of the same age. Their successive breathingrespiratory exchange parameters were collected and analyzed. t test and χ2test were used for2samples comparison, while multiple comparisons amonggroups were performed by using single factor analysis of variance.Correlation analysis was done Pearson correlation test.[Results]（1）Compared with the normal control group, the OUES and OUEP ofthe COPD patient group were significantly lower（P <0.001；P=0.001）.（2）COPD grade Ⅰ to Ⅳ level patients’OUES、OUEP、OUE@AT havea statistical difference with the normal control group’s（F=10.864, P <0.001；F=6.658, P <0.001；F=4.117, P <0.01）by the variance analysis.（3）For further analysis of the multiple comparison, the OUE of theCOPD gradeⅠ h as no significant difference with the normal control group（P >0.05）; the OUES of the COPD grade Ⅱ~Ⅳ was significantly lowercompared with the normal control group（P <0.05）; the OUES of the COPDgrade Ⅲ~Ⅳ was significantly lower compared with the grade Ⅰ~Ⅱ（P<0.05）; the OUES of the COPD grade Ⅲhas no significant difference withthe and grade Ⅳ（P>0.05）. The OUEP and OUE@AT of the COPDgrade Ⅱ~Ⅲ was significantly lower compared with the normal control group（P <0.05）; The OUE@AT of the COPD gradeⅡ~Ⅲ was significantly lowercompared with the gradeⅠ（P <0.05）.（4）The OUES of the COPD patient group has significant positivecorrelate with the FEV1%pred (r=0.581, P <0.001), but the OUEP and theOUE@AT of the COPD patient group didn’t appear significant correlate withthe FEV1%pred（P>0.05）.（5）The the COPD patient group’s OUES、OUEP、OUE@AT issignificantly positive correlate （r=0.500, P <0.001； r=0.516, P <0.001；r=0.625, P <0.001） with the exercise tolerance (peak oxygen uptakeaccounted for a percentage of the predicted value, peak V。O2%pred).[Conclusion] The oxygen uptake efficiency of the patients with COPD issignificantly reduced compared with the normal, and has a significant positivecorrelation with the severity of the airway obstruction and the exercisetolerance.