6 minute walk test in assessing severity of interstitial lung disease: an observational study
6MWT in assessing severity of ILD
DOI:
https://doi.org/10.36141/svdld.v40i2.13991Keywords:
interstitial lung disease; pulmonary function test; quantitative CT; 6 minute walk testAbstract
BACKGROUND: 6 minute walk test (6MWT) is a potential tool in assessing severity of interstitial lung disease (ILD).
OBJECTIVES: To explore the relationship between 6MWT and traditional measures including pulmonary function and chest CT. To determine factors that may influence the 6 minute walk distance (6MWD).
METHODS: 73 patients with ILD were enrolled in the clinic of Peking University First Hospital. 6MWTs, pulmonary CTs and pulmonary function tests were performed and their correlations were analyzed. Multivariate regression analysis was used to determine factors that may impact 6MWD.
RESULTS: 30 (41.4%) of the 73 patients were female, the mean age was 66.1 ±9.6 years. 102 follow-up visits were completed. 6MWD and decrease of SpO2 were both correlated with FEV1, FVC, TLC and DLCO. The volume of normal lung area calculated by the quantitative CT software was positively correlated with 6MWD (r = 0.309, P < 0.01) and negatively correlated with decrease of SpO2 (r = -0.272, P < 0.01). Based on the backward multivariate model ( F = 10.537, P < 0.001, adjusted R2 = 0.509 ), 6MWD was predicted by age, height, body weight, baseline SpO2, increase of heart rate, FEV1, DLCO and FVC.
CONCLUSIONS: The results of 6MWTs were closely correlated with pulmonary function and quantitative CT in patients with ILD . However, aside from disease severity, 6MWD was influenced by personal characteristics and the degree of patient effort, which should be considered by clinicians interpreting 6WMT results.
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Copyright (c) 2023 Zhanwei Hu, Li Gao, Qing Yu, Zhe Jin, Juhong Liu, Yuanyuan Lian, Chengli Que

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