Cardiorespiratory adaptation during 6-Minute Walk Test in fibrotic idiopathic interstitial pneumonia patients who did or did not respond to pulmonary rehabilitation.

BACKGROUND: Pulmonary rehabilitation (PR) improves performance in the 6-min walk test (6MWT) in a subset of patients with fibrotic idiopathic interstitial pneumonia (f-IIP); however, a large proportion of patients does not respond to PR. AIM: To investigate the effects of a PR program on cardiorespiratory responses during a 6MWT and to identify the characteristics of patients who do not show improved performance after PR. DESIGN: An observational study. SETTING: Patients were recruited from the Competence Centre for Rare Pulmonary Diseases at Lille University Hospital, France and completed an 8-week home-based PR program. POPULATION: A total of 19 patients with f-IIP; 12 with idiopathic pulmonary fibrosis (IPF) and 7 with fibrotic non-specific interstitial pneumonia. METHODS: Patients underwent spirometry and completed a 6MWT before and after an 8-week PR program. Gas exchange, heart rate, and pulse O2 saturation were measured continuously during the 6MWT. Quality of life, dyspnea, and anxiety/depression were assessed using the Short-Form 36 (SF-36), the baseline/transition dyspnea index (BDI/TDI), and the Hospital Anxiety and Depression Scale (HADS) questionnaires. RESULTS: Patients who did and did not improve the distance walked in the 6MWT by at least 30 m after PR were classified as responders (N.=9) and non-responders (N.=10), respectively. O2 uptake, ventilation rate, and distance covered during the 6MWT were significantly improved only in the responder group (P<0.05). Changes in SF-36, BDI/TDI, and HADS scores did not differ significantly between responders and non-responders. The non-responder group contained significantly more patients with IPF (P<0.05) and experienced greater arterial oxygen desaturation during the 6MWT compared with the responder group. CONCLUSIONS: Failure to improve performance in the 6MWT after PR was associated with a diagnosis of IPF, non-improvement in gas exchange, and greater arterial oxygen desaturation. CLINICAL REHABILITATION IMPACT: Most f-IIP patients who did not respond to PR were diagnosed with IPF and displayed greater hypoxemia during exercise. Clinical practitioners should seek to determine why patients fail to improve exercise performance after PR and propose an alternative exercise regimen to these patients.

Effects of pulmonary rehabilitation on daily life physical activity of fibrotic idiopathic interstitial pneumonia patients.

Fibrotic idiopathic interstitial pneumonia patients derived benefit from a pulmonary rehabilitation programme in terms of exercise tolerance, anxiety, depression and quality of life without increasing their daily life physical activity http://ow.ly/WV7U30kgNkU.

Relationships between heart rate target determined in different exercise testing in COPD patients to prescribed with individualized exercise training.

BACKGROUND: It has been scientifically proven that pulmonary rehabilitation improves exercise tolerance and facilitates the carrying out of daily physical activities. To optimize the physical and physiological benefits, it is necessary to individualize the training intensity for each patient. The aim of this study is to compare the heart rate (HR) responses to three exercise modalities measuring aerobic fitness in chronic obstructive pulmonary disease patients, in order to easily prescribe individual target HRs for endurance training. PATIENTS AND METHOD: Fifty COPD patients (mean age: 60.1±8.5 years) were included in the study. Each patient carried out a cardiopulmonary exercise test, a 6-minute walk test (6MWT) and a 6-minute stepper test (6MST). During these tests, HR was recorded continuously. After the cardiopulmonary exercise test, the HR was noted at the ventilatory threshold (VT) and at the end of the two exercise field tests (6MWTpeak and 6MSTpeak). The values of the HR during the last 3 minutes of both field tests were averaged (6MWT456 and 6MST456). Finally, the HR at 60% of the HR reserve was calculated with the values of the HR measured during 6MWT and 6MST (HRr60%walk, HRr60%step). RESULTS: The HRs measured during the 6MST were significantly higher than those measured during the 6MWT. The HRr60%step was not significantly different from 6MWT456 and 6MWTpeak HR (P=0.51; P=0.48). A significant correlation was observed between 6MWT456 and 6MWTpeak (r=0.58). The 6MWT456 and 6MWTpeak HR were correlated with HRr60%step (r=0.68 and r=0.62). The VT could be determined in 28 patients. The HRVT was not different from 6MWT456, 6MWTpeak, and HRr60%step (P=0.57, P=0.41 and P=0.88) and was correlated to 6MWT456, 6MWTpeak, and HRr60%step (r=0.45, r=0.40, r=0.48). CONCLUSION: An individualized target HR for endurance training can be prescribed from the HR measured during routine tests, such as 6MWT or 6MST.

Cardiorespiratory Response to Different Exercise Tests in Interstitial Lung Disease.

INTRODUCTION: The 6-min stepper test (6MST) has been used as an alternative to the 6-min walk test (6MWT) to assess exercise tolerance in patients with interstitial lung disease (ILD). Recent data suggest that the tests may involve different energy pathways and cardiorespiratory responses. We thus aimed to compare the cardiorespiratory responses of ILD patients during the 6MWT and the 6MST. METHODS: Thirty-one patients with ILD were randomized to perform both tests in the order 6MST → 6MWT (n = 16) or 6MWT → 6MST (n = 15). Gas exchange, HR, and pulse O2 saturation (SpO2) were measured continuously, and dyspnoea, leg discomfort, and blood lactate concentration were assessed before and immediately after each test. RESULTS: Oxygen uptake (V˙O2) was lower (P = 0.002) and respiratory equivalent ratio for O2 (V˙E/V˙O2) and RER were higher (both P < 0.001) during the 6MST compared with the 6MWT. The 6MST was also associated with higher blood lactate concentrations (6MST, 4.16 ± 1.95 mmol·L; 6MWT, 2.84 ± 1.17 mmol·L; P = 0.01), higher leg discomfort scores (6MST 5 ± 3 points, 6MWT 3 ± 2 points; P < 0.001), and smaller decreases in SpO2 (6MST -5% ± 5%, 6MWT -9% ± 6%; P < 0.001). CONCLUSIONS: ILD patients exhibited greater ventilatory responses and lower arterial O2 desaturation during the 6MST compared with the 6MWT. The higher lactate concentrations and perceived muscle fatigue observed during the 6MST may indicate the presence of intertest differences in active muscle metabolism that could contribute to the distinct cardiorespiratory responses.