Shuttle walk test categorization according to the qualifiers of the International Classification of Functioning, Disability, and Health: proposal for use in patients with difficult-to-treat asthma, a cross-sectional study.

AIM: To classify functional capacity of people with difficult-to-treat asthma based on the International Classification of Functioning, Disability and Health (ICF). METHODS: Fifty-seven patients underwent the Incremental Shuttle Walk Test (ISWT) to assess functional capacity, in order to categorize them functionally we used the ICF qualifiers. To qualify ISWT results the individual's impairment (i.e. percentage of distance walked in relation to the percentage of predicted) was analyzed. Additionally, body mass index (BMI); physical activity level (IPAQ); and pulmonary function were evaluated. In order to analyze the difference between functional capacity levels, two groups were compared (i.e. mild/moderate vs. severe impairment); therefore, the participants were matched according to age and BMI and the unpaired Student t test was used. RESULTS: Among the fifty-seven included individuals, only one (1.8%) presented mild functional capacity limitation, 12 (21.1%) moderate limitation and 44 (77.2%) severe limitation. There was a significant difference between the ISWT distance between groups (F = 0.217, p < .001). The other variables did not present differences between the mild/moderate and severe groups. CONCLUSION: The ICF qualifiers were able to categorize the ISWT and classified the functional capacity limitation as mild, moderate and severe. Therefore, it has proved to be a useful clinical tool for evaluation, follow-up and clinical decision-making.

Reliability of the Shuttle Walk Test With Controlled Incremental Velocity in Patients With Difficult-to-Control Asthma.

PURPOSE: Asthma is a chronic inflammatory condition characterized by bronchial hypersensitivity to endogenous or exogenous agents and variable airflow limitation, which is reversible either spontaneously or with the use of medication. The evaluation of functional capacity in these patients is commonly performed using field tests to gauge activity of daily living. However, the reliability of the symptom-controlled shuttle walk test has not yet been determined for individuals with difficult-to-control asthma. The aim of the present study was to determine the reliability of the shuttle walk test in patients with severe, difficult-to-control asthma. METHODS: Forty-five patients were evaluated including lung function tests, the International Physical Activity Questionnaire (IPAQ), and the Asthma Control Questionnaire. The participants performed a shuttle walk test twice, with a 20-min rest period between tests. RESULTS: The mean distance walked for this cohort was 330.5 m (range, 50-570 m) on the first walk test and 336.3 m (range, 60-571 m) on the second test. There was no statistical difference between the mean distances walked. The Bland-Altman plots of the 2 tests revealed a mean difference of -12.7 m, with a 95% CI of 37.9 to -63.2 m. Significant correlations were found between the distance walked in meters and the IPAQ (r = 0.36, P < .01) and distance in meters and muscle mass (r = 0.39, P < .009). CONCLUSION: The shuttle walk test is reliable for individuals with difficult-to-control asthma and can be used in the evaluation of functional capacity.

Adjuncts to physical training of patients with severe COPD: oxygen or noninvasive ventilation?

BACKGROUND: Previous studies have shown positive effects from noninvasive ventilation (NIV) or supplemental oxygen on exercise capacity in patients with COPD. However, the best adjunct for promoting physiologic adaptations to physical training in patients with severe COPD remains to be investigated. METHODS: Twenty-eight patients (mean +/- SD age 68 +/- 7 y) with stable COPD (FEV(1) 34 +/- 9% of predicted) undergoing an exercise training program were randomized to either NIV (n = 14) or supplemental oxygen (n = 14) during group training to maintain peripheral oxygen saturation (S(pO2)) >/= 90%. Physical training consisted of treadmill walking (at 70% of maximal speed) 3 times a week, for 6 weeks. Patients were assessed at baseline and after 6 weeks. Assessments included physiological adaptations during incremental exercise testing (ratio of lactate concentration to walk speed, oxygen uptake [V (O2)], and dyspnea), exercise tolerance during 6-min walk test, leg fatigue, maximum inspiratory pressure, and health-related quality of life. RESULTS: Two patients in each group dropped out due to COPD exacerbations and lack of exercise program adherence, and 24 completed the training program. Both groups improved 6-min walk distance, symptoms, and health-related quality of life. However, there were significant differences between the NIV and supplemental-oxygen groups in lactate/speed ratio (33% vs -4%), maximum inspiratory pressure (80% vs 23%), 6-min walk distance (122 m vs 47 m), and leg fatigue (25% vs 11%). In addition, changes in S(pO2)/speed, V (O2), and dyspnea were greater with NIV than with supplemental-oxygen. CONCLUSIONS: NIV alone is better than supplemental oxygen alone in promoting beneficial physiologic adaptations to physical exercise in patients with severe COPD.