Comparisons between Different Indices of Exercise Performance in Absolute and Normalized Values in Patients with Chronic Obstructive Pulmonary Diseases

慢性阻塞性肺部疾病患者不同運動功能指標之絕對值與校正值的比較

王儷穎(Li-Ying Wang)；簡盟月(Meng-Yueh Chien)；吳惠東(Huei-Dong Wu)

慢性阻塞性肺疾病 ； 6分鐘行走測驗 ； 漸進式運動測試 ； Chronic obstructive pulmonary disease ； Six-minute walk test ； Graded exercise test

物理治療

29卷1期（2004 / 02 / 01）

21 - 30

英文

Background and Purpose: Exercise is often impaired in patients with chronic obstructive pulmonary disease(COPD). Various test protocols have been used to assess exercise performance in these patients. The purpose of this study was to examine the correlations between different indices of exercise performance in absolute and normalized values measured during 6-minute walk test(6MWT)and graded exercise test(GXT),and their relationship with disease severity in patients with moderate-to-severe COPD. Methods: Sixteen male patients with COPD(mean ± standard error of forced expiratory volume in ones econd (FEV1)=45.3±3.3% predicted)underwent 6MWT and GXT. Main exercise performance indices were distance walked in 6-minute(6MWD), 6-minute walk work(6MWD×W)that was calculated as 6MWD multiplied by the body weight, peak oxygen uptake(VO(subscript 2peak)),and peak power output (W(subscript peak)).These values were expressed as absolute values and as percentage of the predicted value, adjusted for age, race and gender. Results: The disease severity(i.e.% predicted) correlated significantly with absolute 6MWD(r=0.55), 6MWD×W(r=0.61), and absolute and normalized VO(subscript 2peak)(r=0.71 and 0.62,respectively),but not with absolute and normalized W(subscript peak) (r=0.36 and 0.35,respectively). Body mass index and fat free mass index correlated with all exercise performance indices measured during GXT and 6MWT,except for the 6MWD whether normalized or not. The value of6MWD×W had stronger relations with those exercise performance indices measured during the GXT than 6MWD.Conclusions: In patients with COPD, disease severity was best correlated with VO(subscript 2peak)in absolute value. There were good correlations between different indices of exercise performance measured during 6MWT and GXT and the normalization did affect these correlations.

Background and Purpose: Exercise is often impaired in patients with chronic obstructive pulmonary disease(COPD). Various test protocols have been used to assess exercise performance in these patients. The purpose of this study was to examine the correlations between different indices of exercise performance in absolute and normalized values measured during 6-minute walk test(6MWT)and graded exercise test(GXT),and their relationship with disease severity in patients with moderate-to-severe COPD. Methods: Sixteen male patients with COPD(mean ± standard error of forced expiratory volume in ones econd (FEV1)=45.3±3.3% predicted)underwent 6MWT and GXT. Main exercise performance indices were distance walked in 6-minute(6MWD), 6-minute walk work(6MWD×W)that was calculated as 6MWD multiplied by the body weight, peak oxygen uptake(VO(subscript 2peak)),and peak power output (W(subscript peak)).These values were expressed as absolute values and as percentage of the predicted value, adjusted for age, race and gender. Results: The disease severity(i.e.% predicted) correlated significantly with absolute 6MWD(r=0.55), 6MWD×W(r=0.61), and absolute and normalized VO(subscript 2peak)(r=0.71 and 0.62,respectively),but not with absolute and normalized W(subscript peak) (r=0.36 and 0.35,respectively). Body mass index and fat free mass index correlated with all exercise performance indices measured during GXT and 6MWT,except for the 6MWD whether normalized or not. The value of6MWD×W had stronger relations with those exercise performance indices measured during the GXT than 6MWD.Conclusions: In patients with COPD, disease severity was best correlated with VO(subscript 2peak)in absolute value. There were good correlations between different indices of exercise performance measured during 6MWT and GXT and the normalization did affect these correlations.