Objective: To evaluate physical performance on the six-minute walk test (6MWT) in patients with non-cystic fibrosis bronchiectasis and to investigate its relationship with quality of life (QoL). To identify predictors of exercise performance, we also investigated whether six-minute walk distance (6MWD) is associated with clinical and spirometric findings.
Methods: This was a cross-sectional study involving patients with non-cystic fibrosis bronchiectasis (age, > 18 years), with at least one respiratory symptom for > 2 years and an FEV1 < 70% of predicted. Patients underwent clinical evaluation, pulmonary function tests, the 6MWT, and QoL assessment with the Medical Outcomes Study 36-item Short-Form Health Survey (SF-36).
Results: We included 70 patients (48 females). Mean age was 54.5 ± 17.7 years, and mean FEV1 was 44.9 ± 14.5% of predicted. The patients were divided into two groups: 6MWD-low (6MWD below the predicted lower limit; n = 23); and 6MWD-norm (normal 6MWD; n = 47). The following variables were significantly lower in the 6MWD-low group than in the 6MWD-norm group: age; age at diagnosis of bronchiectasis; proportion of former smokers; body mass index (BMI); FEV1% of predicted; and MEP% of predicted. There were no significant differences in the SF-36 scores between the groups. In the logistic regression model, lower age and lower BMI were significantly associated with lower 6MWD.
Conclusions: In this sample, there was a high proportion of patients who presented a lower than expected 6MWD. Although 6MWD was not related to QoL, it was associated with age and BMI.