Abstract
Background: Relationships between the 6-minute walk test (6MWT) and cardiopulmonary exercise test (CPET) performance have been established in some respiratory diseases. However, in patients with bronchiectasis (BECTs) data are scant in the literature.
Aim: To evaluate relationships between 6MWT distance and CPET performance, lung function (LF) and arterial blood gases (ABG) in patients with stable bronchiectasis.
Methods: A retrospective evaluation of 27 patients with BECTs who attended a rehabilitation program and who had 6MWT, CPET in cycle ergometer, LF and ABG (at rest) evaluation at the start of the program. Spearman's correlation coefficient was used for statistical analysis.
Results: Thirteen male and 14 female with ages ranging from 19 to 75 (median 51 yrs). Sixteen patients were severely obstructed and 11 had airway colonisation. Mean 6MWT distance was 440,4 meters and mean end test saturation was 89,30%. Mean maximal work (MW) was 68,1 Watts and mean end-CPET saturation was 89,37%. Positive correlations were found between 6MWT distance and MW (r=0.721**; p=0.000), VO2max (r=0.551**; p=0.003), VO2max/kg (r=0.497**; p=0.008), PaO2 (r=0.485*; p=0.010) and HgbSat (r=0.481*; p=0.013). No correlations were found between 6MWT distance and FVC, FEV1, FEV1/FVC, residual volume or PaCO2. Considering colonised patients, positive correlations were found between 6MWT distance and VO2max, VO2max/kg, PaO2 and HgbSat at the 0.05 level.
Conclusions: 6MWT is a simple test that seems to mirror exercise capacity evaluated by CPET in patients with bronchiectasis. None of the LF parameters evaluated reflected 6MWT distance in these patients.
- © 2011 ERS
