Prognostic value of 6-minute walk test in idiopathic pulmonary fibrosis

Objective To evaluate the prognostic value of 6-minute walk test (6MWT) in idiopathic pulmonary fibrosis (IPF). Methods A systematic search was performed in PubMed, Embase, Cochrane databases, Wiley, Ovid, Medline.All studies that reported 6MWT as a prognostic indicator in IPF were included.This meta-analysis was performed using RevMan 5.0. Results 1 248 patients from 13 studies were included in the meta-analysis.The results showed that walk distance and oxygen saturation in 6MWT were associated with the mortality of IPF.Walk distance on 6MWT was associated with the mortality of IPF (OR=0.99, 95% CI: 0.99-1.00, P<0.000 01). Higher oxygen saturation at rest and at end of 6MWT were also associated with lower mortality (OR=0.82, 95% CI: 0.76-0.88, P<0.000 01; OR=0.93, 95% CI: 0.91-0.95, P<0.000 01). Moreover, change in oxygen saturation in 6MWT was associated with increased mortality of IPF (OR=1.23, 95% CI: 1.09-1.39, P=0.000 9). Compared to controls, patients with oxygen saturation <88% in 6MWT was associated with increased mortality of IPF (OR=1.83, 95% CI: 1.12-2.99, P=0.02). Conclusions 6MWT is a prognostic indicator in IPF.Lower levels of oxygen saturation and walk distance in 6MWT are associated with increased mortality of IPF patients. Key words: Idiopathic pulmonary fibrosis; 6-minute walk test; Oxygen saturation