Original Article
Study on the relationship between exercise-induced desaturation by 6-minute walking test and lung function in patients with chronic obstructive pulmonary disease
Yang Lulu, He Jiaze, Qumu Shiwei, Yang Ting
Published 2021-05-20
Cite as Int J Respir, 2021, 41(10): 744-750. DOI: 10.3760/cma.j.cn131368-20210201-00088
Abstract
ObjectiveTo study the incidence of exercise induced desaturation (EID) induced by 6-minute walking test (6MWT) in patients with chronic obstructive pulmonary disease (COPD), and explore the relationship between EID and lung function.
MethodsA total of 67 patients with stable COPD from January 2019 to December 2020 in the China-Japan Friendship Hospital were selected, and retrospectively analyze their lung function and 6MWT results.The enrolled patients were divided into 2 groups according to whether EID occurred during the 6MWT process, and the relationship between the 6-minute walking distance (6MWD) and lung function of the two groups was evaluated.The ROC curve analyzes the value of 6MWD and related indicators of lung function in predicting the occurrence of EID in patients with COPD.
ResultsA total of 67 patients with stable COPD were included, with an average age of (64±11) years.The incidence of EID was 71.6% (48/67). Comparing COPD patients with and without EID, the terms of age, height, weight, body mass index (BMI), resting saturation of peripheral oxygen (SpO2 rest), and forced vital capacity to predicted value ratio (FVC%pred), forced expiratory volume in the first second to predicted value ratio (FEV1%pred) was not statistically significant (all P>0.05). But at 6MWD, minimum saturation of peripheral oxygen during exercise (SpO2min), the difference between resting and minimum saturation of peripheral oxygen (ΔSpO2), diffusion capacity for carbon monoxide in single breath to predicted value ratio (DLCO SB%pred), diffusion capacity for carbon monoxide per liter of alveolar volume to predicted value ratio (DLCO/VA%pred), the differences were statistically significant (all P<0.05). Pearson correlation analysis showed that 6MWD, DLCO SB%pred, DLCO/VA%pred, SpO2min and EID were negatively correlated, and the difference was statistically significant (all P<0.001). Among them, the thresholds of DLCO SB%pred, DLCO/VA%pred and 6MWD to predict the occurrence of EID in COPD patients were 75.8%, 80.9%, and 410.0 m, respectively.
ConclusionsContinuous measurement of blood oxygen saturation in 6MWT can find more EID events in COPD patients.DLCO SB%pred<75.8%, DLCO/VA%pred<80.9% and 6MWD <410.0 m can be used to predict the occurrence of EID in patients with COPD, among which DLCO SB%pred has a slightly better predictive ability.It is necessary to pay attention to the possibility of EID in patients with COPD, and timely intervention and oxygen therapy.
Key words:
Pulmonary disease, chronic obstructive; Pulmonary rehabilitation; 6-minute walk test; Exercise induced desaturation
Contributor Information
Yang Lulu
Capital Medical University, Beijing 100069, China
He Jiaze
Capital Medical University, Beijing 100069, China
Qumu Shiwei
Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, China-Japan Friendship Hospital, National Center for Respiratory Medicine, Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, National Clinical Research Center for Respiratory Diseases, WHO Collaborating Centre for Tobacco Cessation and Respiratory Diseases Prevention, Beijing 100029, China
Yang Ting
Department of Pulmonary and Critical Care Medicine, Center of Respiratory Medicine, China-Japan Friendship Hospital, National Center for Respiratory Medicine, Institute of Respiratory Medicine, Chinese Academy of Medical Sciences, National Clinical Research Center for Respiratory Diseases, WHO Collaborating Centre for Tobacco Cessation and Respiratory Diseases Prevention, Beijing 100029, China
