[Pulmonary rehabilitation, a historical perspective from Hippocrates to tele-rehabilitation]. / La réadaptation respiratoire, une perspective historique: d'Hippocrate à la télé-réadaptation.

In ancient times Hippocrates described a disease, the 3rd phthisis, which seems to correspond to COPD and is mainly treated by walking, gradually increasing the number of steps until reaching 10,000 steps a day at the end of the initial period of treatment. The recent era began in the second half of the 20th century and ended in 2015, with an unusual Cochrane Library editorial in which it was stated that the accumulated evidence (statistically significant and clinically relevant improvements in clinical signs, tolerance to exercise, quality of life, days hospitalization…) on the effects of rehabilitation programs suffice to suspend research on the subject and to justify focus on new elements in the programs. It is essential, in fact, to establish uniform practical recommendations for the prescription of routine rehabilitation (number and duration of physical activity sessions, therapeutic education, re-training intensity…). In addition, studies should be carried out on new practices: community or home rehabilitation, long-term rehabilitation, tele-rehabilitation.

[Applicability of the Arabic version of the French quality of life' (QOL) questionnaire (VQ11) in Tunisian patients with chronic obstructive pulmonary disease]. / Évaluation de la version arabe du questionnaire français de qualité de vie « VQ11 ¼ chez des patients tunisiens atteints de bronchopneumopathie chronique obstructive.

BACKGROUND: There is no validated Arabic version of the French questionnaire of quality of life, the VQ11. This study aimed to test the applicability of the Arabic version of the VQ11 in Tunisian patients with chronic obstructive pulmonary disease (COPD). METHODS: It was a prospective and cross-sectional study, spread over seven months, that included 40 stable COPD male patients. The Arabic version of VQ11, translated by a bilingual expert, was used. The functional, psychological, relational and total scores were calculated. Patients were divided into two groups according to the GOLD classification: "A-B" (n=25) and "C-D" (n=15). A significant correlation-coefficient (r) of≥0.51, between the VQ11 total score and the ADO index (age, dyspnoea, obstruction), and higher quality of life scores in GOLD "C-D" when compared to GOLD "A-B" would be in favour of application of the Arabic version of the VQ11. RESULTS: The mean±standard deviation of age, post-bronchodilator FEV1/FVC, ADO index and VQ11 total score were 64±8 years, 0.55±0.08, 4.8±1.7 and 2±10, respectively. A significant "r" (0.56) was identified between the ADO index and the total score. Psychological, relational and total scores of GOLD "A-B" patients were significantly lower than those in GOLD "C-D" patients: 10±4 vs. 12±3, 11±4 vs. 13±3 and 30±11 vs. 36±7, respectively. CONCLUSION: The Arabic version of VQ11 is applicable in Tunisian COPD patients with reliable results.

[Home-based exercise training and physical activity level over one year in COPD patients]. / Réentraînement à l'effort à domicile et niveau d'activité physique à un an chez les patients BPCO.

INTRODUCTION: The aim of our study was to investigate whether exclusive home-based training was feasible and effective in COPD patients and if patients have a persistent improvement in their level of physical activity after this intervention. METHODS: One hundred COPD patients (FEV1=42.6% predicted) first underwent 25 weekly sessions of supervised cycle ergometry training, followed by one year of monthly supervised follow-up. Six minutes walking test, endurance test, BODE index and activity monitoring were performed before, after and one year after inclusion. RESULTS: About 80% of the patients completed the program. They improved their exercise tolerance and their daily physical activity level, even one year after inclusion. However, more severe patients did not maintain these benefits. Daily physical activity quantity was also decreased in these patients one year after inclusion. CONCLUSION: This home-based exercise training program is feasible and effective. Improvements are sustainable for the majority of patients. However, severe patients were not able to maintain these benefits. Other exercise training strategies may have to be considered in these patients.

A comprehensive rehabilitation program improves disease severity in patients with obstructive sleep apnea syndrome: a pilot randomized controlled study.

BACKGROUND: Exercise training may improve components of metabolic syndrome and obstructive sleep apnea syndrome (OSAS). The objective of our pilot randomized controlled study was to determine the benefits of a short intensive inpatient individualized exercise training (IET) program in sedentary untreated OSAS patients. METHODS: Twenty-two sedentary patients with moderate to severe OSAS were randomly assigned either to one-month education activity sessions (n=11; control group) or to inpatient rehabilitation program (n=11), including IET, education activities sessions, and dietary management. Full polysomnography (PSG), OSLER (Oxford Sleep Resistance test), body composition, anthropometric measurements, metabolic syndrome components, and questionnaires were performed at baseline and at study end point. RESULTS: No changes occurred in the control group in all variables. Compared to controls, participants randomized to the IET group presented a significant decrease in apnea-hypopnea index (AHI) (40.6±19.4 vs. 28.0±19.3; P<0.001), oxygen desaturation index (ODI), and arousal index, which occurred in conjunction with significant decrease in body mass index (BMI), neck circumference, fat mass, fasting glucose, and diastolic blood pressure. Increased sleep latency was found in participants in the IET group with altered values at baseline. CONCLUSIONS: IET reduced OSAS severity with improvement of metabolic syndrome components with concomitant loss in body fat in sedentary adults. If confirmed on a larger scale, a comprehensive rehabilitation program could constitute an additional or alternative treatment for moderate to severe OSAS patients.

Decreased fat oxidation during exercise in severe obstructive sleep apnoea syndrome.

AIM: To assess whether the severity of obstructive sleep apnoea syndrome (OSAS) is associated with altered fat oxidation (FO) during physical exercise in men with type 2 diabetes (T2DM) and/or the metabolic syndrome (MetS). METHODS: A total of 105 consecutive overweight or/and T2DM male patients were hospitalized for metabolic check-ups including bioimpedancemetry to measure lean body mass (LBM), standardized exercise calorimetry to assess FO, maximum fat oxidation (MFO) and carbohydrate oxidation (CHO), and OSAS screening using respiratory polygraphy. Twenty patients were classified as having severe OSAS, according to the apnoea/hypopnoea index (AHI), with greater than 30 events/h (mean AHI: 45.2±14.3 events/h). They were group-matched for age, BMI, and the presence of T2DM and/or MetS with two other OSAS groups: mild (AHI<15 events/h [n=20]; mean AHI: 8.8±4.5 events/h); and moderate (AHI>15 events/h and<30 events/h [n=20]; mean AHI: 23.7±4.2 events/h). RESULTS: MFO adjusted for LBM was severely decreased in the severe OSAS group (1.6±1.0 mg.min(-1).kgLM(-1)) compared with the moderate (2.5±0.9 mg.min(-1).kgLM(-1); P=0.008) and mild (2.9±0.8 mg.min(-1).kgLM(-1); P=0.003) groups. All exercise-intensity levels (20%, 30%, 40% and 60% of the theoretical maximum aerobic power) showed reduced FO levels between the severe and mild-to-moderate OSAS groups. However, no differences in CHO were seen at any level of exercise between groups. Pearson's correlation analysis showed that AHI and the oxygen desaturation index were negatively associated with MFO corrected for LBM (r=0.41 and r=0.37, respectively; P<0.005). CONCLUSION: OSAS severity is associated with altered FO during exercise.

Spirometric profile of narghile smokers.

INTRODUCTION: Studies of the spirometric profiles of narghile smokers are few, have some methodological limits (i.e. small sample size), and present contradictory conclusions. AIMS: (i) To determine the percentage of narghile smokers with obstructive ventilatory defect (OVD) and/or restrictive ventilatory defect (RVD) or static hyperinflation (SHI); (ii) to compare the chronological and estimated lung ages. INCLUSION CRITERIA: men aged 20 to 60 years, narghile smokers (>1 narghile-year [NY]). EXCLUSION CRITERIA: cigar or cigarette smokers and comorbidity. Narghile use quantification: NY and kg of cumulative tobacco use (1 NY=9.125 kg of cumulative tobacco use). DEFINITIONS: Large airway obstructive ventilatory defect (OVD): forced expired volume in one second (FEV(1))/forced vital capacity (FVC) less than lower limit of normal (LLN). Small airway OVD: FVC more than LLN and decrease (less than LLN) of one or more peripheral flows. RVD: total lung capacity (TLC) less than LLN. SHI: residual volume (RV) more than upper limit of normal. SPIROMETRIC MEASURES: (Vmax 22 Series/6200 Autobox, SensorMedics, Yorba Linda, California, USA with measurement of functional residual capacity by nitrogen washout). Measurements were made according to international recommendations. RESULTS: One hundred and ten narghile smokers were included (34±10 years; 1.76±0.07m; 84±14kg). Thirty-six percent of the subjects had SHI; 14% had small airway OVD; 14% had RVD, and 6% had large airway OVD. Estimated lung age was higher than chronological lung age (47±18 years vs. 34±10 years, P<0.05). CONCLUSION: Narghile use accelerates lung ageing. This study provides the health authorities with valid arguments to fight this blight on society, which increasingly involves children and pregnant women.

Skeletal muscle effects of electrostimulation after COPD exacerbation: a pilot study.

Muscle dysfunction is a major problem in chronic obstructive pulmonary disease (COPD), particularly after exacerbations. We thus asked whether neuromuscular electrostimulation (NMES) might be directly useful following an acute exacerbation and if such a therapy decreases muscular oxidative stress and/or alters muscle fibre distribution. A pilot randomised controlled study of NMES lasting 6 weeks was carried out in 15 in-patients (n=9 NMES; n=6 sham) following a COPD exacerbation. Stimulation was delivered to the quadriceps and hamstring muscles (35 Hz). Primary outcomes were quadriceps force and muscle oxidative stress. At the end of the study, quadriceps force improvement was statistically different between groups (p=0.02), with a significant increase only in the NMES group (median (interquartile range) 10 (4.7-11.5) kg; p=0.01). Changes in the 6-min walking distance were statistically different between groups (p=0.008), with a significant increase in the NMES group (165 (125-203) m; p=0.003). NMES did not lead to higher muscle oxidative stress, as indicated by the decrease in total protein carbonylation (p=0.02) and myosin heavy chain carbonylation (p=0.01) levels. Finally, we observed a significant increase in type I fibre proportion in the NMES group. Our study shows that following COPD exacerbation, NMES is effective in counteracting muscle dysfunction and decreases muscle oxidative stress.

Cost-saving effect of supervised exercise associated to COPD self-management education program.

BACKGROUND: Although the benefits of comprehensive pulmonary rehabilitation have been demonstrated in patients with COPD, the effects of exercise sessions within self-management programs remain unclear. We hypothesized that 8 supervised exercise sessions incorporated in a 1-month self-management education program in COPD patients would be effective to improve health outcomes and to reduce direct medical costs after one year, compared to usual care. METHODS: In this randomized controlled trial, 38 moderate-to-severe COPD patients were assigned either to an intervention group or to a usual care group. The hospital-based intervention program provided a combination of 8 sessions of supervised exercise with 8 self-management education sessions over a 1-month period. The primary end-point was the 6-min walking distance (6MWD), with secondary outcomes being health-related quality of life (HRQoL)--using the St. George's Respiratory Questionnaire (SGRQ) and Nottingham Health Profile (NHP), maximal exercise capacity and healthcare utilization. Data were collected before and one year after the program. RESULTS: After 12 months, we found statistically significant between-group differences in favor of the intervention group in 6MWD (+50.5 m (95%CI, 2 to 99), in two domains of NHP (energy, -19.8 (-38 to -1); emotional reaction, -10.4 (-20 to 0)); in SGRQ-symptoms (-14.0 (-23 to -5)), and in cost of COPD medication (-480.7 € (CI, -891 to -70) per patient per year). CONCLUSION: The present hospital-based intervention combining supervised exercise with self-management education provides significant improvements in patient's exercise tolerance and HRQoL, and significant decrease of COPD medication costs, compared to usual care.

[Chronic obstructive pulmonary disease (COPD) in the elderly]. / La bronchopneumopathie chronique obstructive (BPCO) du sujet âgé en huit questions/réponses.

Chronic obstructive pulmonary disease (COPD) is a chronic disease characterized by incompletely reversible airflow limitation, measured by a decrease of FEV(1)/FVC ratio. International consensus does not agree on a single threshold for this ratio, which can define airflow obstruction. Although the prevalence of COPD in the elderly population varies according to the definition used, it definitely increases with age and could reach 15% in those over 65 years of age. Therefore, ageing of the population should result in increased prevalence and socioeconomical costs of COPD during coming years. In France, diagnosis of COPD in the elderly is difficult, late and insufficient. Management, which has the same goals as in younger populations, has to be global and coordinated. Some points should be considered with particular attention considering the cumulative risks related on the one hand to COPD and on the other to ageing: pharmacological side-effects, decreased physical and social autonomy, nutritional impairment, comorbidities. Given the lack of specific data in elderly populations, pharmacological indications are generally considered to be the same as in younger populations, but some additional precautionary measures are necessary. Pulmonary rehabilitation seems to be beneficial at any age. Palliative care comes up against important difficulties: an indefinite beginning of the palliative stage in COPD; insufficient palliative care resources; insufficient communication; insufficient utilization of palliative care resources. Global COPD management in elderly requires coordination, best reached in health care network organizations involving medical and/or social professionals.

[The VQ11, a short health-related quality of life questionnaire for routine practice in COPD patients]. / Le VQ11, un questionnaire de qualité de vie spécifique à la BPCO utilisable en clinique.

OBJECTIVE: The management of COPD aims to improve integrated indices such as health-related quality of life (HRQoL). Experts recommend repeated and methodical assessment of HRQoL, particularly by the use of questionnaires. Though these tools give pertinent information for groups of patients, they have limitations in describing the progress in one patient or indicating the prognosis. The purpose of this study is to validate a brief, self-administered HRQoL questionnaire, designed for the individual follow-up of COPD patients over a period of 3-6 months. METHOD: Following an initial validation of the contents and a review of the literature, 166 COPD patients completed an experimental version of a questionnaire including 24 items, three theoretical components (functional, psychological and relational) and 11 sub-dimensions. RESULTS: Confirmative factor analyses show a hierarchical model in respect of the current criteria (chi(2)=62.042; dl=41; ratio chi(2)/ddl=1.51; p<0.02; CFI=0.955; TLI=0.939; RMSEA=0.056; SRMR=0.054) composed of 11 items (one by a theoretical sub-dimension) distributed in three components (functional=3; psychological=4; relational=4). CONCLUSION: The questionnaire obtained, named VQ11, possesses an internal validation which satisfies international psychometric standards. It remains necessary to demonstrate whether the questionnaire satisfies the criteria of external validation and that it reveals thresholds of clinical change.

[Electrostimulation in the rehabilitation of patients with severe COPD: pertinent or not]. / L'électrostimulation dans la réhabilitation des patients BPCO sévères : pertinence ou facétie?

INTRODUCTION: The degree of dyspnoea and muscular dysfunction during an exacerbation of COPD are so severe in some patients that they are unable to follow a traditional exercise training programme based on whole body activity (walking, cycling). Some alternative strategies like electrostimulation may be considered to initiate retraining as soon as possible, to break the vicious circle of exacerbations and improve the prognosis of these patients. LITERATURE: Five randomised studies with a control group have analysed the effects of electrostimulation in COPD. They show that this technique does not cause dyspnoea and is well tolerated by the patients regardless of their severity; that that it can improve peripheral muscular function, effort tolerance, dyspnoea and quality of life. CONCLUSIONS: The preliminary results seem to indicate that electrostimulation probably has a place in respiratory rehabilitation. We think that it should be considered as an alternative to classical retraining in COPD patients with loss of independence during an exacerbation. However, further larger, standardised studies are necessary to confirm the clinical and functional benefits of this technique, to understand the underlying mechanisms and define the precise therapeutic indications.

[Spirometric profile of narghile smokers]. / Profil spirométrique des fumeurs de narguilé

INTRODUCTION: Studies of the spirometric profile of narghile smokers are few, have some methodologic limits (ie. small sample size) and present contradictory conclusions. OBJECTIVE: (i) To determine the percentage of smokers having an obstructive ventilatory defect (OVD) and/or a restrictive ventilatory defect (RVD) or static hyperinflation (SHI). (ii) To compare the chronological and the estimated lung ages. INCLUSION CRITERIA: men aged 20-60 years smoking narghile (>1 narghile-year (NA). Non-inclusion criteria: cigar or cigarettes smoker and co-morbidity. Narghile consummation quantification: NA and kg of cumulated tobacco (1 NA=9.125 kg of cumulated tobacco). DEFINITIONS: large airway OVD: FEV1/FVCLLN and forced mid expiratory flowupper limit of normal. Spirometric measures (Vmax 22 Series/6200 Autobox, Yorba Linda, California, USA with measurement of functional residual capacity by nitrogen washout). Measurements were made according to international recommendations. RESULTS: 110 narghile smokers were included (34+/-10Yr; 1.76+/-0.07m; 84+/-14kg). 36% of subjects had SHI; 14% had small airway OVD; 14% had RVD and 6% had large airway OVD. (ii) Estimated lung age was higher than the chronological lung age (47+/-18Yr vs 34+/-10Yr, p<0.05). CONCLUSION: Narghile consumption accelerates ageing of the lung. This study provides the health authorities with valid arguments to fight this blight on society which increasingly involves children and pregnant women.

Cost-sparing effect of twice-weekly targeted endurance training in type 2 diabetics: a one-year controlled randomized trial.

OBJECTIVE: We evaluated the effects of targeted, moderate endurance training on healthcare cost, body composition and fitness in type 2 diabetes patients routinely followed within the French healthcare system. DESIGN AND METHODS: A total of 25 type 2 diabetic patients was randomly assigned to one of two groups: 13 underwent a training programme (eight sessions, followed by training twice a week for 30-45 minutes at home at the level of the ventilatory threshold [V(T)]); and 12 received their usual routine treatment. Both groups were followed for one year to evaluate healthcare costs, exercise effectiveness and a six-minute walking test. RESULTS: The training prevented loss of maximum aerobic capacity, which decreased slightly in the untrained group (P=0.014), and resulted in a higher maximum power output (P=0.041) and six-minute walking distance (P=0.020). The Voorrips activity score correlated with both V(O2max) (r=0.422, P<0.05) and six-minute walking distance (r=0.446, P<0.05). Changes in V(O2max) were negatively correlated with changes in body weight (r=0.608, P<0.01). Training decreased the insulin-resistance index (HOMA-IR) by 26% (P<0.05). Changes in percentages of fat were correlated to changes in waist circumference (r=0.436, P<0.05). The total healthcare cost was reduced by 50% in the trained group (euro 1.65+/-1 per day versus euro 3.00+/-1.47 per day in the untrained group; P<0.02) due to fewer hospitalizations (P=0.05) and less use of sulphonylureas (P<0.05). CONCLUSION: Endurance training at V(T) level prevented the decline in aerobic working capacity seen in untrained diabetics over the study period, and resulted in a marked reduction in healthcare costs due to less treatments and fewer hospitalizations.

An innovative maintenance follow-up program after a first inpatient pulmonary rehabilitation.

Although the benefits of pulmonary rehabilitation (PR) have been demonstrated in patients with COPD, most studies suggest that short-term programs are insufficient to maintain the benefits beyond a post-discharge period of 6 months to 1 year. We were interested to evaluate the effects of an innovative maintenance intervention compared with a usual after-care. Forty moderate to severe COPD patients, who had just completed their first inpatient PR, were consecutively included in either a maintenance group (MG) or a standard after-care group. The maintenance program was coordinated within a health-care network including self-help associations, and offered weekly activities. We measured the 6-min walk distance (6MWD), the quality of life using the St George Respiratory Questionnaire (SGRQ), the dyspnea, the maximal workload and the health-care utilization. Data were collected at respiratory clinic admission and discharge, and at 6- and 12-month visits after the PR. After 12 months, we found statistically and clinically significant differences in favor of the MG in 6MWD (74 m; p < or = 0.01) and in the three domains of SGRQ: symptom (19%; p < or = 0.01), activity (27%; p < or = 0.01) and impact (32%; p < or = 0.01). The results showed no difference between groups in dyspnea and maximal workload. We also found that the number of days spent in hospital for respiratory disorders was significantly lower in the MG after 12 months (p < or = 0.03). The multidisciplinary management of COPD patients in the post-rehabilitation period within a health-care network including self-help associations seems to be an effective strategy for maintaining, and even improving, the benefits of a first initial structured program.

[Incidence of individualized training on exercise-induced desaturation in COPD patients]. / Effets d'un réentraînement individualisé sur la désaturation à l'exercice des sujets atteints de BPCO.

BACKGROUND: Exercise-induced desaturation is a well-described phenomenon in COPD patients during exercise assessments such as the six minute walk test (6MWT). Some of the pathophysiological mechanisms involved in this O2 desaturation could be modified by individualized exercise training as part of a pulmonary rehabilitation programme. The aim of this study was to determine the effect of pulmonary rehabilitation on O2 desaturation exhibited by COPD patients during a 6MWT. METHODS: Twenty COPD patients (FEV1=61.1 +/- 3.2% predicted) who exhibited O2 desaturation before rehabilitation (mean 7.3 +/- 0.7% with a mean duration of 5.3 +/- 0.1 min) participated. They performed four weeks of RP including individualized whole-body exercise training achieving a mean 9.3 +/- 0.27 hours per week of exercise tailored to their ventilatory threshold. RESULTS: Dyspnoea at the end of the test, ventilatory threshold and FEV1 were retained as correlates of desaturation before rehabilitation. After rehabilitation, 6MWT distance increased (p<0.01) with reduced dyspnoea (p<0.05). Two sub-groups were identified: persistent desaturaters (DS, n=13) and non-desaturaters group (NDS, n=7). There were no baseline differences between the two groups. After rehabilitation only the persistent desaturaters showed a significant increase in distance achieved during 6MWT associated with a reduced dyspnea (p<0.05). This group showed a mean O2 desaturation equal to 8.1 +/- 0.9% which persisted to 5 +/- 0.3 min. A tendency to a lower dyspnoea at the end of 6MWT performed before rehabilitation was observed in NDS compared with DS (p<0.058). CONCLUSION: It seems that responses to a pulmonary rehabilitation programme including individualized exercise training could act on O2 desaturation. Indeed 7 of 20 (35%) COPD patients exhibiting O2 desaturation during a 6MWT showed no O2 desaturation after rehabilitation programme while 13 on 20 (65%) do it.

[What are the post-rehabilitation options for patients with COPD?]. / Quelles solutions pour l'après-réhabilitation des patients BPCO?

INTRODUCTION: The efficacy of pulmonary rehabilitation in the short term for patients with Chronic Obstructive Pulmonary Disease (COPD) is now clearly established. However, several studies have shown that these benefits last only for between 6 months to one year. On the basis of the current literature, the authors believe that a follow-up of rehabilitation "post-rehabilitation" is necessary not only to maintain benefits but also to reinforce them. STATE OF THE ART: We review studies that have focused specifically on post-rehabilitation and found a heterogeneity of tested solutions. As with conventional pulmonary rehabilitation, a multidisciplinary approach including physical activity, health education and psychosocial supports seem to be the key to successfully maintain rehabilitation's gains. PERSPECTIVES: Further randomised and controlled research will be needed to confirm the medical and economic effectiveness of this combination of intervention in patients with different severities of COPD. CONCLUSION: Individualised, objective and coordinated follow-up activities allow COPD patients to cope with the chronicity of their disease and the unpredictability of symptoms in the context of daily life.

Is impairment similar between arm and leg cranking exercise in COPD patients?

UNLABELLED: Impaired skeletal muscle function has been reported in patients with chronic obstructive disease (COPD), but such impairment is not homogenous and its distribution between the upper and the lower limbs is still unclear. The present study was designed to assess and compare upper and lower limb capacities in patients with moderate to severe COPD during incremental and constant-load exercises. Thirteen COPD patients of similar age with moderate to severe air flow limitation (FEV(1): 35%+/-5% predicted) and 19 healthy subjects were studied. Four sessions were organized: two incremental and two constant-load cycling exercises with arm or leg in randomized order. As observed in a previous study involving incremental and constant tests, power, VO(2), RER, VE, and HR were all significantly lower in the upper and lower limbs of patients with COPD than in healthy controls. In the healthy population, aerobic capacity and mechanical efficiency (ME) were lower in the course of arm exercises than in leg exercises. For the same relative workload, dyspnea and blood lactate production were higher during arm exercise. In contrast, no significant difference was observed between arm and leg capacities for any of these parameters in COPD patients. CONCLUSION: Although aerobic capacity is impaired in COPD patients, arm aerobic capacity is relatively preserved. Given the lack of significant difference between arm and leg capacities in COPD, we hypothesize that upper limb muscles are less compromised than lower limb muscles in this patient population.

Nitrogen washout slope in poorly controlled asthma.

Short-term control of asthma is often lacking even though forced expiratory volume in 1 s (FEV1) remains above normal value. Small airways are a potential key site of persistent inflammation and structural modification. Noninvasive assessment of small airways was found to be difficult, but the computerized single breath nitrogen washout test (SBNT) has been recently successfully reintroduced with this aim. Twenty-four asthmatics (13 females) of various severity but with normal FEV1 were compared with 24 healthy volunteers (13 females) and studied at steady-state after bronchodilatation (400 microg salbutamol). Spirometric values, plethysmographic data, phase III (slope of phase III of the SBNT, dN2) and IV [closing volume (CV), with closing capacity (CC) = CV + residual volume (RV)] of the SBNT were checked. Asthma severity, recent control, exacerbation rate, and therapy requirements were assessed on the basis of validated questionnaires (ACQ) and international guidelines. Patients were prospectively pooled into two equal groups according to their exacerbation rate. The reproducibility of the measurements obtained on 2 following days was assessed. All plethysmographic values, except total lung capacity (TLC), differentiated asthmatic patients from controls. The CC/TLC [124 (117-148) vs 117 (112-123), P = 0.04] and dN2 [110 (99-190) vs 94 (75-111), P = 0.02] were increased in asthma. The dN2 was significantly increased in patients with frequent exacerbations [100 (83-105) vs 195 (141-212), P = 0.0005]. A correlation was obtained between dN2 and recent asthma control (rho: 0.62; P = 0.003), number of exacerbations (rho: 0.71, P = 0.0008), and RV/TLC (rho: 0.49, P = 0.026). This study demonstrated that ventilation inequalities assessed by dN2 represent an important indicator of poor asthma control and high exacerbation rate in high symptom perceivers. New therapies focused on small airways should now be developed.