Six-minute stepper test to assess effort intolerance in interstitial lung diseases.

The six-minute stepper test (6MST) is a new test for evaluating exercise tolerance. Unlike the six-minute walk test (6MWT) it can be carried out in a limited space. The aim of this study was to compare the 6MST and the 6MWT in patients with various diffuse interstitial lung disease (ILD). 6MWT and 6MST were performed the same day in 84 patients with various ILD. The covered distance during 6MWT was compared to the number of steps during the 6MST. We also compared heart rate, oxygen saturation, dyspnoea and leg tiredness on a Borg scale. All the patients successfully completed the tests, and tolerance was considered good. The number of steps completed in the 6MST was strongly correlated with the distance walked in the 6MWT (r2 = 0.5; p < 0.0001). Oxygen desaturation was less frequent and less severe (p < 0.0001), heart rate was higher (p < 0.0001) and dyspnoea and leg tiredness were more marked (p < 0.0001) in the 6MST than in the 6MWT. The 6MST is feasible for patients with ILD. It is a simple, safe, mobile test that is cheap and easy to carry out in all structures.

[Therapeutic patient education in respiratory rehabilitation]. / Éducation thérapeutique du patient au cours de la réadaptation respiratoire.

INTRODUCTION: Therapeutic patient education (TPE) is an essential component of pulmonary readaptation in chronic respiratory diseases. Numerous and varied patient education projects offer heterogeneous contents and methods, which render them difficult to analyze and to compare. The objective of this review was to provide perspective on the main principles of patient education, using a non-exhaustive approach. STATE OF KNOWLEDGE: This review is focused on patient education using a patient-centered approach, physician-patient partnership and self-management, which are presented at once pragmatically and conceptually. One of the main objectives of TPE is the acquisition of self-management skills by patients with a chronic disease, which will be considered from a clinical standpoint. Lastly, TPE will be assessed in the overall framework of patient-centered pulmonary readaptation. PERSPECTIVES: TPE needs to be structured in view of assessing its effects. It is consequently essential for caregivers to receive continuous training so as to more clearly understand the methods employed, the objective being to build evaluable contents contributing to performance of multicentric trials. CONCLUSION: Current literature on TPE emphasizes the extent to which the patient remains the central actor in his or her care pathway. If patients are called upon to modify their behaviors, it is equally necessary that caregivers proceed likewise, adopting postures favoring the acquisition and appropriation by the patient of skills that shall be required as he or she learns to live with chronic disease.

[Physical activity and pulmonary rehabilitation in adults with asthma]. / Apports de l'activité physique et de la réadaptation respiratoire dans l'asthme de l'adulte.

Physical activity is reduced in people with asthma compared to the general population, especially in situations where patients have uncontrolled asthma symptoms, persistent airflow obstruction and other long-term medical problems, in particular obesity and anxiety. Exertional dyspnea, which is of multifactorial origin, is the main cause of reduced physical activity reduction and draws patients into a vicious circle further impairing quality of life and asthma control. Both the resumption of a regular physical activity, integrated into daily life, adapted to patients' needs and wishes as well as physical and environmental possibilities for mild to moderate asthmatics, and pulmonary rehabilitation (PR) for severe and/or uncontrolled asthmatics, improve control of asthma, dyspnea, exercise tolerance, quality of life, anxiety, depression and reduce exacerbations. A motivational interview to promote a regular programme of physical activity in mild to moderate asthma (steps 1 to 3) should be offered by all health professionals in the patient care pathway, within the more general framework of therapeutic education. The medical prescription of physical activities, listed in the Public Health Code for patients with long-term diseases, and pulmonary rehabilitation should be performed more often by specialists or the attending physician. Pulmonary rehabilitation addresses the needs of severe asthma patients (steps 4 and 5), and of any asthmatic patient with poorly controlled disease and/or requiring hospitalized for acute exacerbations, regardless of the level of airflow obstruction, and/or with associated comorbidities, and before prescribing biological therapies.

[How to improve patient's access to Respiratory Rehabilitation?] / Comment améliorer l'accès des patients à la réadaptation respiratoire ?

Despite effectiveness and clear international guidelines, respiratory rehabilitation remains underutilized: less than 15% of suitable patients in France and worldwide receive this treatment. The factors of this lack of referral and uptake have been studied and are not limited to a problem of quantitative adequacy of supply and demand. The lack of knowledge of health professionals, patients, payers, heterogeneous programs which does not necessary correspond to the needs of the patient (modalities, geography, duration), the lack of trained and available professionals, the profile of patients and prescribers and the quality of the programs are identified as potentially hindering the completion of a rehabilitation program. It is essential to analyze these barriers and to find solutions to the greatest number of respiratory patients can benefit optimal healthcare and integrate into a coherent care planning.

Long-term effects of pulmonary rehabilitation on daily life physical activity of patients with stage IV sarcoidosis: A randomized controlled trial.

INTRODUCTION: Pulmonary rehabilitation (PR) is known to improve exercise tolerance, mood, and quality of life in patients with chronic respiratory diseases. The aim of this work was to determine whether PR provides long-term benefits in increasing daily life physical activity in patients with chronic sarcoidosis. METHODS: This randomized prospective study (registered ClinicalTrials.gov NCT02044939) of 38 patients with stage IV chronic sarcoidosis was performed between 2012 and 2016. Patients were assigned to participate in a 2-month PR program (n=20) or receive counseling (n=18). Assessments were performed at baseline, 2 months (end of the PR program), 6months, and 12months, and included daily life physical activity parameters (measured for 5 consecutive days), exercise tolerance, dyspnea, anxiety, depression, fatigue, and quality of life. The primary outcome was the 12-month change in time spent in activities above an estimated energy expenditure of 2.5metabolic equivalents (METs). Secondary daily life physical activity outcomes included number of steps per day, total daily energy expenditure, and total energy expenditure above 2.5METs. RESULTS: The primary outcome did not differ between the two groups; mean between-group differences were -13.2min (95% confidence interval [CI]: -76.3 to 49.8) at 6 months and -18.1min (95% CI: -55.7 to 19.4) at 12months. Although PR had no effect on secondary daily life physical activity outcomes, it did significantly increase exercise tolerance at 6 and 12 months and decrease the dyspnea score at 6 months and the fatigue score at 12months. CONCLUSION: This trial failed to demonstrate a beneficial effect of PR on daily life physical activity in sarcoidosis patients, suggesting that long-term behavioral programs may be necessary to complement PR.

Influence of DISC behavioral profile on the short- and long-term outcomes of home-based pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

INTRODUCTION: Pulmonary rehabilitation (PR) programs are commonly prescribed for patients with severe respiratory disorders, but little is known about how the patient's personality traits influence PR outcomes. We analyzed the response of patients with chronic obstructive pulmonary disease (COPD) to a home-based PR program according to their predominant behavioral profiles using the Dominance - Influence - Steadiness - Conscientiousness (DISC) tool. METHODS: This was a retrospective observational study of 335 COPD patients referred by their pulmonologists between January 2010 and December 2015. The DISC behavioral profile was determined at the beginning of the program. Patients received individual supervised sessions at home once a week for 8 weeks, which consisted of exercise training and psychosocial, motivational, and educational support, all tailored to the participant's DISC profile. Exercise tolerance (6-minute stepper test, 6MST), anxiety and depression (Hospital anxiety and depression scale, HADS), and quality of life (Visual simplified respiratory questionnaire, VSRQ) were evaluated immediately before and after the PR program (T0 and T2, respectively) and then 6 and 12 months later (T8 and T14, respectively). Responders were defined as patients who exhibited at least minimal clinically important differences (improvements) from baseline. RESULTS: Of the 335 COPD patients, 102 (30.4%), 98 (29.3%), 82 (24.5%), and 53 (15.8%) were classified as having predominant D, I, S, and C behavioral traits, respectively. All four patient groups showed significantly (P<0.01) improved performance in the 6MST, HADS, and VSRQ evaluations at T2 (n=300), T8 (n=262), and T14 (n=231) compared with T0, and the proportion of responders in all groups at T8 and T14 was high (∼60%). The percentage of responders differed significantly between groups only at T2, when the S group contained fewer responders on the HADS anxiety subscale. Most patients who did not complete the study were classified as D type (42/102, 41.2%), followed by I (28/98, 28.6%), S (22/82, 26.8%), and C (12/53, 22.6%) types. CONCLUSION: The personality profile of COPD patients influenced their adherence to, but not their benefit from, a home-based PR program. The high proportion of patients in all personality groups showing significant improvements in outcomes supports a personalized approach to the design of PR programs.

[Home-based pulmonary rehabilitation in idiopathic pulmonary fibrosis]. / Réhabilitation respiratoire à domicile au cours de la fibrose pulmonaire idiopathique.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a severe chronic lung disease. Pulmonary rehabilitation could improve the quality of life of patients with this condition. METHODS: We prospectively evaluated the impact of an 8 week home-based pulmonary rehabilitation program over 10 months in stable patients suffering from IPF. Exercise capacity, pulmonary function, dyspnea and quality of life were analyzed before and after the rehabilitation program. RESULTS: 17 patients were included and 13 completed the study. Mean FVC was 2.15+/-0.79 L and mean DLCO was 7.81+/-3.99 ml/min/mmHg. Six patients were treated with low dose oral steroids ($20 mg/day of prednisone) with or without immunosuppressive treatments; 6 were taking part in therapeutic trials. Mean endurance time (7.4+/-9.1 min vs 14.1+/-12.1 min; p<0,01), number of beats per minute on a stepper (322+/-97 vs 456+/-163; p=0.026), 6 min walking distance to heart rate ratio (11+/-6 vs 17+/-12; p=0.006), exercise dyspnea (p=0.026), sensation of physical limitation at the SF-36 (25%+/-26 vs 49%+/-38; p=0.047) and 4 out of 7 visual analog scales were significantly improved after rehabilitation. In contrast, no significant difference was observed in resting pulmonary function or in other items of quality of life questionnaires CONCLUSION: A home-based program of pulmonary rehabilitation is feasible in IPF patients. It significantly improves endurance parameters and physical limitation in this patient group without changing pulmonary function.

[Cardiopulmonary exercise testing for the diagnosis of unexplained dyspnea: a review of 194 cases]. / Épreuve fonctionnelle à l'exercice et dyspnée inexpliquée : à propos de 194 cas.

INTRODUCTION: Chronic dyspnoea that remains unexplained after resting pulmonary function and cardiovascular testing is a common problem in clinical practice. The aim of this study was to determine the utility of cardiopulmonary exercise testing (CPET) in the diagnosis of unexplained dyspnoea. METHODS: This retrospective single-centre study included consecutive patients with dyspnoea who had normal resting cardiopulmonary examinations (including chest X-ray, electrocardiography, pulmonary function tests [PFTs], and cardiac ultrasound). CPET was performed using a cycle ergometer with analysis of blood gases. The results were interpreted as being most likely due to one of the six pathophysiological mechanisms shown below. Consensus required agreement between at least three of the authors. RESULTS: Of the 194 patients included (median age 53 years, sex-ratio (M:F) 0.83, mean body mass index 27.3±5.36kg/m2), 32% of the test profiles were compatible with deconditioning, 20% with inappropriate hyperventilation (without gas exchange abnormalities), 18% with disorders of gas exchange, 13% with sub-maximal CPET, 9% with cardiovascular anomalies, and 8% with normal CPET. Of the patients with gas exchange abnormalities, the most common causes were bronchiectasis (6), emphysema (6), recent pneumonia (2), and diffuse interstitial pneumonitis (2). Ten of the patients with cardiovascular abnormalities had chronotropic insufficiencies, 5 had excessive tension responses, and 3 had disorders of rhythm or repolarisation. CONCLUSIONS: CPET may greatly facilitate the diagnosis of unexplained dyspnoea. More than 50% of the dyspnoea cases examined here were due to deconditioning or hyperventilation syndrome and would benefit from a simple pulmonary rehabilitation program.

[The DISC tool improves communication and results in pulmonary rehabilitation]. / L'outil DISC améliore la communication et les résultats de la réhabilitation respiratoire : une approche comportementale adaptée.

INTRODUCTION: Competence in personal relationships is essential for a caregiver, especially in pulmonary rehabilitation (PR). Considering the behavioral profile of patients might help to optimize their management and the results of PR. METHODS: We evaluated eight hundred and thirty-two consecutive patients with chronic respiratory disease who received eight weeks of home-based PR. Their exercise tolerance (six-minute stepper test, 6MST), mood (HAD), and quality of life (VSRQ, MRF28) were evaluated at the beginning and end of PR. For six hundred and ninety patients, a behavioral approach was implemented at the beginning of PR by using the DISC tool to identify four behavioral profiles: dominance, influence, steadiness, conscientiousness. The remaining 142 patients served as the control group. RESULTS: Subjectively, the therapeutic alliance was more easily established with the behavioral approach. Compared with the control group, patients with the "steadiness" profile were younger (60.7±12 years) and mostly female (52.8%), whereas patients with the "conscientiousness" profile were older (67.5±10.6 years) and mostly male (85.5%). The four behaviorally profiled groups showed no differences in exercise tolerance, mood, or quality of life scores at baseline. Globally, all patients improved their exercise tolerance, mood and quality of life. The percentage of responders to 6MST and VSRQ (>MCID) was 7.5% and 5.3% higher with the behavioral approach. For non-responders to 6MST and VSRQ (

At identical isowork rates, ageing influences cardiorespiratory adaptations in COPD out-patients.

PURPOSE: To determine the extent to which younger COPD patients improve their cardiorespiratory function during exercise in comparison with older COPD patients, as a result of exercise training. METHODS: Thirty-nine COPD patients underwent an exercise program. They were divided into two groups: a younger group (57.2+/-1.0 years, n=18 patients) and an older group (68.8+/-0.6 years, n=21 patients). Forced expiratory volume in 1s was lower than 55% of the predicted value for all patients. RESULTS: After training, VO2 symptom-limited significantly improved by 10.3% and 8.4% for the younger and older COPD patients, respectively (P<0.05). Peak power significantly improved by 25.2% and 17.8% in the younger and older groups, respectively (P<0.05) with a greater improvement for the younger group (P<0.05). At submaximal exercise, ventilation and heart rate significantly decreased after training in the younger COPD patients (P<0.05) with no significant modification in the older COPD patients. CONCLUSIONS: The results suggest that all patients with COPD benefit from exercise rehabilitation at maximal exercise workload, however, according to their age, submaximal cardiorespiratory adaptations were greater in younger patients.

Six-minute stepper test: a valid clinical exercise tolerance test for COPD patients.

INTRODUCTION: Exercise tolerance testing is an integral part of the pulmonary rehabilitation (PR) management of patients with chronic obstructive pulmonary disease (COPD). The 6-minute stepper test (6MST) is a new, well-tolerated, reproducible exercise test, which can be performed without any spatial constraints. OBJECTIVE: The aim of this study was to compare the results of the 6MST to those obtained during a 6-minute walk test (6MWT) and cardiopulmonary exercise testing (CPET) in a cohort of COPD patients. METHODS: Ninety-one COPD patients managed by outpatient PR and assessed by 6MST, 6MWT, and CPET were retrospectively included in this study. Correlations between the number of steps on the 6MST, the distance covered on the 6MWT, oxygen consumption, and power at the ventilatory threshold and at maximum effort during CPET were analyzed before starting PR, and the improvement on the 6MST and 6MWT was compared after PR. RESULTS: The number of steps on the 6MST was significantly correlated with the distance covered on the 6MWT (r=0.56; P<0.0001), the power at maximum effort (r=0.46; P<0.0001), and oxygen consumption at maximum effort (r=0.39; P<0.005). Performances on the 6MST and 6MWT were significantly improved after PR (570 vs 488 steps, P=0.001 and 448 vs 406 m, respectively; P<0.0001). Improvements of the 6MST and 6MWT after PR were significantly correlated (r=0.34; P=0.03). CONCLUSION: The results of this study show that the 6MST is a valid test to evaluate exercise tolerance in COPD patients. The use of this test in clinical practice appears to be particularly relevant for the assessment of patients managed by home PR.

Effects of itraconazole therapy in allergic bronchopulmonary aspergillosis.

STUDY OBJECTIVES: Allergic bronchopulmonary aspergillosis (ABPA) is the result of an immune reaction to antigens of Aspergillus fumigatus, which colonizes the bronchial lumen of affected individuals. Presently, the recommended treatment of ABPA, mainly for acute episodes of exacerbations, is administration of glucocorticoids. We initiated this study to analyze the effects of itraconazole on the clinical, biological, and functional parameters in patients with ABPA. PATIENTS: in this report, we describe the follow-up of 14 asthmatic patients who presented with ABPA. During the 2-year reference period (a 2-year period before the introduction of itraconazole), 14 patients were treated with inhaled corticosteroids and 12 of the 14 received oral glucocorticoids. During the itraconazole treatment period, the patients were treated with oral itraconazole, 200 mg/d, for at least 12 months. RESULTS: During the 2-year reference period, no significant clinical, immunologic, and functional improvement was observed on a long-term basis. During the itraconazole treatment period, a clinical improvement was observed. Blood eosinophilia, serum total IgE levels, and serum precipitating antibodies against A fumigatus antigen significantly decreased. No decrease of specific IgE against A fumigatus spp was observed. All patients experienced a partial improvement in pulmonary function tests: FEV(1) significantly increased from 1,433 +/- 185 to 1,785 +/- 246 mL/s (p < 0.01). All patients successfully lowered oral glucocorticoid dose when receiving itraconazole. In 7 of 14 patients receiving itraconazole, the removal of oral glucocorticoids was possible. CONCLUSION: These results demonstrate the efficacy of itraconazole in ABPA in reducing or eliminating the need for glucocorticoid therapy, along with clinical, biological, and functional improvement.

Release of superoxide anion by alveolar macrophages in pulmonary sarcoidosis.

Biological mechanisms involving nonprotease factors mediate the alterations of the alveolar structures which lead to the interstitial fibrosis of pulmonary sarcoidosis. Thus, we have investigated the production of oxidant species by BAL cells from 50 sarcoidosis patients and 18 healthy controls using a lucigenin-dependent CL method. Spontaneous and PMA-induced CL's were significantly higher in untreated patients and treated patients than in spontaneously cured patients or healthy controls (p less than .05). SOD inhibits 60 to 75% of spontaneous CL and 91 to 93% of PMA-induced CL. There was no apparent correlation between the CL of AM's and the radiological types, SACE levels, and gallium scans. In marked contrast, CL was significantly higher in patients with increased alveolar lymphocytosis (greater than or equal to 18%) than in patients with normal BAL. Since there were neither neutrophils nor eosinophils in BAL and since lymphocytes do not produce lucigenin-dependent CL, we believe that CL is produced by AM's. CL inhibition by SOD suggests that superoxide anion is involved in the production of CL. The release of both superoxide anion and related radicals may be of importance in the pathogenesis of pulmonary sarcoidosis.

[The significance of maximal expiratory concentrations of CO2 (MEC CO2) in the negative diagnosis of acute pulmonary embolism in chronic obstructive bronchopneumopathies]. / Intérêt de la concentration expiratoire maximale de CO2 (CEM CO2) pour le diagnostic négatif de l'embolie pulmonaire aiguë au cours des bronchopneumopathies chroniques obstructives.

The aim of this prospective study was to analyse the contribution of the measurement of alveolar arterial gradients of CO2 during forced expiration in the diagnosis of pulmonary emboli occurring in chronic airflow obstruction (COPD) as a result of smoking. The study was carried out on 178 patients: Group 1: 54 subjects without emboli (14 controls, 33 COPD and 7 patients with chest pain); Group 2: 72 patients with proved emboli (49 non COPD, 23 COPD); Group 3: 52 patients COPD presenting with varied non-embolic broncho-pulmonary pathology (pneumonia, bronchospasm, pulmonary oedema, bronchial neoplasm). The diagnosis of pulmonary emboli was confirmed by scintigraphy in patients with non COPD or angiography (in patients with COPD). The maximal fraction of CO2 was measured using a capnologue during a forced expiration which was long and prolonged until residual volume was achieved. The PaCO2 was measured simultaneously by an analysis of arterial blood gases. The D index was calculated according to the formula [(PaCO2-PEM CO2)/PaCO2] x 100. The D index was significantly lower in Group 1 (3.42 +/- 3.8% p < 0.0001) than in Group 2 (20.8 +/- 10%) and Group 3 (17.6 +/- 11.7%) (not significant between Groups 2 and 3). In patients with COPD the specificity and sensitivity and the predicted positive and negative value were 100% for a D limit of 7%. In COPD patients these values were respectively 82, 95, 75 and 96% for a D limit of 7%; on the other hand for a D below 5% the values were 60, 100, 64 and 100% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of ambulatory respiratory rehabilitation on exercise tolerance and quality of life in chronic obstructive lung disease patients]. / Effets de la réhabilitation respiratoire en ambulatoire sur la tolérance à l'effort et la qualité de vie des patients atteints de bronchopneumopathie chronique obstructive.

Respiratory rehabilitation is a multidisciplinary medical approach which allows a total care of patients suffering from COPD. Optimisation of bronchodilator treatment, health education, cessation of smoking, dietetic, relaxation and re-entrainment to effort. We report out experience concerning 88 BPCO (mean age 62.1, FEV1 of 1.4 litres; or 48% of predicted normal); these 88 patients were cared for on an ambulatory basis at our centre for two hours per session, three times per week for seven weeks. The objective results were analysed on exercise tests before and after treatment. For ventilation, there was a significant improvement in the power developed (from 45.5+/-17.1 to 53.4+/-23 watts; p<0.001) without any change in the oxygen consumption (VO2), ventilation (VE) or heart rate (FC) and of oxygen pulse (VO2/FC). For the same level of power (80% of maximum power for the initial exercise test) there was a significant lowering of ventilation (V=33.5+/-9.4 to 30.7+/-7.4 litres per minute, p<0.001), cardiac frequency (FC: from 116.9+/-16 to 111.1+/-13.1 beats per minute, p<0.001) as well as the oxygen pulse (VO2/FC: from 7.9+/-2.7 to 8.3+/-3.7). At the maximum on the exercise test all the parameters studied were significantly better: watts, VO2, VE, cardiac frequency and VO2/FC. A study of the visual analogue scale (EVA), analysing sleep, anxiety, dyspnoea and the physical aspects showed a significant improvement in the four subjective parameters. Respiratory rehabilitation of BPCO practiced as an out patient has shown an improvement in exercise tolerance in every day activities and improvement in dyspnoea and in the quality of life.

[Exercise test in prescribing respiratory rehabilitation]. / Epreuve d'effort dans la prescription de la réhabilitation respiratoire.

Pulmonary rehabilitation is indicated to a wide population of patients suffering of pulmonary diseases often associated to a cardiovascular disorder. Best evaluation of the results of an exercise program, must consider the alterations of pulmonary function tests, the cardiac dysfunction, the non specific bronchial hyperresponsivness and the lung inflation. Exercise test is often performed on a cycle ergometer with an incremental or a constant load. The indications of the exercise test are: diagnostic (evaluation of effort performance, ventilatory drive and looking for an associated disorder as cardiovascular, muscles or metabolic), therapeutic (individualization of exercise program) and scientific (objective evaluation of immediate and long term results).

[Interpreting exercise tests]. / Interprétation de l'épreuve d'effort.

The main objective of the maximal exercise test is to measure a patient's exercise limit and to identify the cause. The test to be interpreted is evaluated first by judging exercise tolerance on the basis of maximal oxygen consumption (VO2max or symptom-limited VO2(VO2 SL). Intolerance is moderate if VO2 is under 85% of the theoretical level and severe when it is under 60%. Interpretation then consists in identifying the cause of the limitation. Ventilatory reserve is the main element for determining whether the limitation is due to ventilatory or cardiac impairment. In case of a ventilatory limitation, ventilatory reserve falls and the ventilatory pattern and gasometric values orient the diagnosis to emphysema, diffuse interstitial lung disease or bronchopneumopathy. If the ventilatory reserve rises, the limitation has cardiac as origin and in this case the oxygen pool is decreased. Persistence of chronotrope reserve can indicate coronary artery disease while the VD/VT ratio is useful for differentiating cardiac and vascular limitations. Peripheral limitations usually produce an early major increase in blood lactate, a high lactate/pyruvate ratio, with lactate or ventilatory thresholds under 40% of theoretical VO2max, especially in case of muscle pain and low watt equivalent. Nevertheless, these parameters cannot be used to confirm a precise diagnosis. The only positive diagnosis given by the exercise test concerns glycogenolysis disorders (por example McArdle's disease) seen as a total absence of increased lactate level. In conclusion, the exercise test is a means of assessing a patient's exercise tolerance and provides arguments for determining the origin of the limitation. However, as no one argument is truly pathognomonic, the diagnosis hypothesis must be based on all the elements available from clinical examination and complementary explorations.

[Blood lactate three minutes after a graded exercise test: a criterion of maximal exercise in patients with COPD]. / Lactatémie trois minutes après une EFX : un critère de maximalité chez le patient BPCO.

INTRODUCTION: The graded exercise test (GXT) is used to measure the exercise capacity of patients with chronic obstructive pulmonary disease (COPD). To do this GXT must be maximal (exhaustive). However, the value of the blood lactate at the GXT endpoint [La(-)max] or after a recovery period of three minutes [La(-)recovery], to confirm that the GXT is maximal, remains controversial. The purpose of the present study is to determine a threshold of [La(-)max] and/or [La(-)recovery], which confirms the exhaustiveness of GXT in patients with COPD. METHODS: Thirty-six patients with COPD performed a GXT until exhaustion on a cycle ergometer. During the GXT cardiorespiratory parameters, [La(-)max] and [La(-)recovery] were measured. When at least three out of five of the most frequently used criteria to confirm exhaustion were met, GXT was considered as maximal. Conversely, GXT was considered as sub-maximal when less three criteria were observed. The receiver operating characteristic (ROC) curves were analyzed. RESULTS: For [La(-)max] the areas under the ROC curve and the areas under the diagonal were not significantly different (P=0.16). For [La(-)recovery] the ROC curve inflected itself at 5.8mmol/L (sensitivity=0.92 and specificity=0.56). CONCLUSIONS: It was not possible to use [La(-)max] to confirm exhaustion in our population. However, [La(-)recovery]<5.8mmol/L may help to confirm non-exhaustion during GXT in patients with COPD. Below this blood lactate threshold 93% patients performed a sub-maximal GXT.