Severe Airway Obstruction Research Articles

Improvement in Snoring and Sleep Apnea after Adenotonsillectomy in Children of 3 To 10 Years of Age

Background: Variability is found about the severity of upper airway obstruction ranging from primary snoring to obstructive sleep apnea syndrome (OSAS). Adenotonsillectomy (AT) is taken as the primary treatment option. Objective: To evaluate the efficacy of Adenotonsillectomy among children having obstructive sleep apnea syndrome. Methodology: This was a cross-sectional study conducted at Bahawal Victoria Hospital Bahawalpur from January 2017 to January 2018. A total of 52 children of both genders, aged 3 to 10 years, having obstructive sleep apnea syndrome (OSAS) and selected for Adenotonsillectomy (AT) were enrolled. Adenotonsillectomy was performed in all the study participants employing general anesthesia. Preoperative and postoperative characteristics as well as respiratory and sleep parameters were compared adopting chi-square test for qualitative variables while t-test was employed for quantitative variables. Results: Out of a total of 52 children, 32 (61.5%) were male. The majority of the children, 27 (51.9%) were between 3-6 years of age. Statistically significant improvement (p-value < 0.05) was noted at the postoperative interval following AT for obstructive AHI score, respiratory disturbance index, obstructive apnea and hypopnea index, SpO2 nadir, TSpO2<90%, and respiratory arousal index. Obstructive AHI score < 1 episode / hour was seen in 37 (71.2%) children while AHI score < 5 episodes / hour were noted in 47 (90.4%). Conclusion: Adenotonsillectomy for obstructive sleep apnea syndrome improved quality of life and polysomnographic parameters in most of the children.

Evaluation of balance in patients with chronic obstructive pulmonary disease with practical tests.

Patients with chronic obstructive pulmonary disease (COPD) have impaired balance and hence fall more frequently. Easy application of balance evaluation tests can prevent the loss of time in the outpatient clinic for patients with COPD. In this study, we aimed to compare the efficacy of Berg Balance Scale (BBS), a time-consuming but a widely used test, with other easy-to-perform tests such as the Single Leg Stance (SLS), Five Repetition Sit to Stand (5STS), Four Step Square (FSST), and Timed Up and Go (TUG) tests. A total of 71 patients with COPD and 70 control subjects with matching demographic characteristics were included in the study. All patients undertook pulmonary function tests and their scores of 6-min walk-test (6MWT), modified Medical Research Council (mMRC) dyspnoea scale, COPD assessment questionnaire (CAT) and body mass index (B) were recorded. In addition, the severity of airway obstruction (O), the dyspnoea severity (D) and exercise capacity (E) (BODE) index scores were measured. All patients with COPD were classified into four groups, A to D, based on the GOLD 2017 criteria. All subjects undertook the BBS, SLS, 5STS, FSST and TUG tests. Balance tests revealed increased balance impairment in patients with COPD in comparison with the control subjects (P<.05). The BBS, SLS, FSST and TUG examinations suggested that balance impairment was frequent in Groups C and D patients with COPD (P<.05). FSST and TUG had the highest correlation with BBS (r=-.812 and -.842 and P<.001 and <.001, respectively). The results of FSST and TUG were the closest to those of BBS test. FSST and TUG tests can be applied for the assessment of bodily balance status among patients with COPD in outpatient clinics.

Pre-emptive extracorporeal membrane oxygenation to support endobronchial stenting for severe airway obstruction.

Tracheobronchial stent insertion is a common palliative intervention for the management of dynamic airway collapse due to severe tracheobronchomalacia or tracheal compression due to mass effect [1]. Airway stents are usually placed bronchoscopically with or without fluoroscopy. In more complex cases, airway stents are placed using a rigid bronchoscope under general anaesthesia with conventional or jet ventilation. In patients where advancement of a rigid bronchoscope into the distal airway or ventilation through a rigid bronchoscope may be difficult, pre-emptive awake veno-venous extracorporeal membrane oxygenation should be considered. This report is the first publication to describe a novel technique in a series of patients being treated for critical airway obstruction who would otherwise be at risk of respiratory arrest at the induction of anaesthesia.

Astımlı çocuklarda leptin, adiponektin ve karnitin düzeylerinin akciğer fonksiyonları, astım şiddeti ve BMI ile ilişkisinin değerlendirilmesi

Purpose: The aim of this study is to evaluate the relationship between serum levels of leptin, adiponectin and carnitine with lung function, disease severity and BMI (Body Mass Index) in children with asthma. Materials and methods: 97 Pediatric patients with not in acute attack period bronchial asthma and 40 healthy control subjects were included in the study. Pulmonary function tests done to all asthma patients with a spirometer. Children with asthma were divided into 3 groups according to GINA criteria, mild intermittent, mild persistent, and moderate persistent, with using symptoms and spirometric parameters according to the severity of airway obstruction. Leptin, total carnitine and adiponectin analyzes were performed from venous blood by ELISA method. Results: Patient group serum leptin values were found to be significantly higher than the control group serum leptin values (p = 0.001). Patient group serum total carnitine values were found to be significantly lower than the control group (p = 0.001). Moderate persistent group adiponectin and total carnitine values were found to be significantly lower than mild intermittent group (p <0.05). A weak negative correlation was found between leptin and total carnitine, eosinophil, BMI values. A weak negative correlation was found between total carnitine and eosinophil, BMI values. A moderate negative correlation was found between age and leptin, adiponectin, total carnitine values. Conclusions: It suggested that leptin levels increased, adiponectin and total carnitine levels decreased in children with asthma and at the same time the decrease in adiponectin and total carnitine levels may be associated with disease severity.

Higher body mass index is associated with increased lung stiffness and less airway obstruction in individuals with asthma and fixed airflow obstruction.

Higher body mass index (BMI) is associated with less severe airway obstruction in older asthma patients with fixed airflow obstruction. This is potentially mediated through BMI-related mechanisms that increase lung stiffness (i.e. reduce lung compliance). https://bit.ly/3jBwCNy

Periodontal Status, Its Treatment Needs, and Its Relationship with Airflow Limitation and Quality of Life in COPD Patients.

Chronic obstructive pulmonary disease (COPD) is one of the most prevalent respiratory diseases in the world. There is an impressive relationship between periodontal status and airflow limitation in patients with COPD. Therefore, in this study, we aimed to investigate the periodontal status, its treatment needs, and its relationship with the severity of airway obstruction and quality of life in patients with COPD. In this case-control study, 36 healthy men (control group) and 35 men afflicted with COPD (case group) were investigated. On the basis of spirometry results and Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria, patients with COPD were further divided into 4 groups. The participants' quality of life was evaluated using COPD Assessment Test (CAT) questionnaire. Thereafter, both groups of participants were referred to a dentistry clinic so that the related specialist could investigate their periodontal health status. The relationship between the periodontal indices and the variables under study including GOLD stage, CAT score, Forced Expiratory Volume in first second and Forced Vital Capacity (FEV1/FVC) ratio, Forced Expiratory Volume in first second (FEV1), and the exacerbation rate were statistically analyzed using independent t-test, one-way analysis of variance, Tukey's test, and Pearson correlation coefficient. The results revealed that probing pocket depth (PDD), bleeding on probing (BOP), and loss of attachment (LOA) are negatively correlated with FEV1% (r=-0.53, p=0.001), (r=-0.62, p=0.001), and (r=-0.72, p=0.001) as well as FEV1/FVC ratio (r=-0.45, p=0.007), (r=-0.47, p=0.004), and (r=-0.61, p=0.001), respectively. The results showed that PDD, BOP, and LOA are positively correlated with CAT score (r=0.51, p=0.002), (r=0.47, p=0.004), and (r=0.71, p=0.001), respectively. Periodontal problems are positively associated with COPD severity as determined by GOLD criteria and negatively associated with quality of life of patients with COPD.

Surgical Management of Anterior Glottic Webs.

Congenital webs are rare and represent <5% of all congenital laryngeal anomalies. They are usually a partial laryngeal atresia rather than a true web, and present as a thick and fibrotic web with subglottic extension and associated subglottic stenosis. All patients with a congenital anterior glottic web should be evaluated for chromosome 22q11.2 deletion syndrome. Management strategies are mainly based on the severity of airway obstruction and the anatomical extension of the webs. Simple division of the web endoscopically may be adequate for rare thin webs, however, an open approach is usually warranted for thick glottic webs regardless of Cohen grades. Open repair can be either with keel placement or reconstruction of the anterior commissure.

"Optimal surfactant delivery protocol using the bovine lipid extract surfactant: a quality improvement study".

ImportanceEpisodes of severe airway obstruction (SAO) are reported during surfactant administration.ObjectiveTo evaluate adherence to and impact of a surfactant protocol on adverse events.MethodsAn evidence-based protocol for surfactant administration was developed (2011), implemented (2012) and re-implemented (2014), including three major steps: lung recruitment, manual bagging, and bolus instillation. Three epochs were evaluated: E0 (2010), E1 (2015) and E2 (2018). Adherence was defined as compliance with all steps. Adverse events such as hypoxia (<80%) and severe airway obstruction (SAO) were investigated.Results197 infants (246 administrations) were included: E0 81 (110), E1 52 (63), and E2 64 (73). Adherence improved from 49% (E1) to 67% (E2). Full adherence to protocol significantly decreased SAO from 26% to 1.25% (E2; p < 0.005) and hypoxia/bradycardia events (5 to 0% E2; p < 0.005), without any side effects.ConclusionsAdherence to a surfactant administration protocol improved over time and significantly decreased important adverse events.

Total Antioxidant Status in Stable Chronic Obstructive Pulmonary Disease.

ObjectiveThis study evaluates the total antioxidant status (TAS) in plasma of stable chronic obstructive pulmonary disease (COPD) patients. Earlier studies of their relationship showed inconsistent findings.Patients and MethodsWe compared TAS between 90 COPD patients and 30 age- and sex-matched controls (mean age 67 ± 7.9, 87 males and 33 females) according to airway obstruction severity, gender, smoking status (current/ former/ non-smoker), smoking-dose, the number of exacerbations in the previous year, nutritional status and hypercapnia.ResultsThere were no differences in pack-years between COPD and controls, neither in COPD groups. The median time from the last exacerbation was 5 months (interquartile range 3−8.3). TAS was significant higher in COPD than controls (1.68 [1.55−1.80] versus 1.59 [1.54−1.68], respectively; P = 0.03). TAS was significantly higher in COPD men than women (1.7 [1.6−1.8] versus 1.57 [1.5−1.7], respectively; P = 0.001). In COPD groups, there were no significant differences between the severity of airway obstruction and TAS. We found significant positive correlation between pack-years and TAS in all participants (Rho = 0.429, P = 0.004) and COPD patients (Rho = 0.359, P = 0.02), but not in controls. TAS was a significant predictor of COPD (β = 3.26; P = 0.04; OR = 26.01; 95% CI: 1.20 to 570.8). We failed to find significant differences between TAS and smoking status, frequency of exacerbations in the previous year, nutritional status and hypercapnia.ConclusionTAS was a significant predictor of COPD. TAS was a significantly higher in stable COPD than controls, higher in COPD men than women, but there was no significant correlation between TAS and the airway obstruction severity. Our results suggest that it could be appropriate to include the time from the last exacerbation in the oxidant–antioxidant balance analysis of COPD patients.

Overnight airway obstruction severity prediction centered on acoustic properties of smart phone: validation with esophageal pressure

Objective: Obstructive sleep apnea is characterized by a number of airway obstructions. Esophageal pressure manometry (EPM) based estimation of consecutive peak to trough differences (ΔPes) is the gold standard method to quantify the severity of airway obstructions. However, the procedure is rarely available in sleep laboratories due to invasive nature. There is a clinical need for a simplified, scalable technology that can quantify the severity of airway obstructions. In this paper, we address this and propose a pioneering technology, centered on sleep related respiratory sound (SRS) to predict overnight ΔPes signal. Approach: We recorded streams of SRS using a bedside iPhone 7 smartphone from subjects undergoing diagnostic polysomnography (PSG) studies and EPM was performed concurrently. Overnight data was divided into epochs of 10 s duration with 50% overlap. Altogether, we extracted 42 181 such epochs from 13 subjects. Acoustic features and features from the two PSG signals serve as an input to train a machine learning algorithm to achieve mapping between non-invasive features and ΔPes values. A testing dataset of 14 171 epochs from four new subjects was used for validation. Main results: The SRS based model predicted the ΔPes with a median of absolute error of 6.75 cmH2O (±0.59, r = 0.83(±0.03)). When information from the PSG were combined with the SRS, the model performance became: 6.37cmH2O (±1.02, r = 0.85(±0.04)). Significance: The smart phone based SRS alone, or in combination with routinely collected PSG signals can provide a non-invasive method to predict overnight ΔPes. The method has the potential to be automated and scaled to provide a low-cost alternative to EPM.

Respiratory health effects of the fiberglass-reinforced plastic lamination process in the yacht-building industry.

Objectives:Fiberglass-reinforced plastics (FRP) manufacturing has been related to cases of severe airway obstruction and elevated risk of respiratory mortality. But the specific job content risk is not clear. This study evaluated the respiratory health effects of the FRP lamination process.Methods:A questionnaire was used to evaluate respiratory symptoms of workers in two yacht-building plants. Pre-shift (07:30–08:30 hours) and post-shift (17:00–18:00 hours) lung function was measured, while post-shift induced sputum was collected on the first day of the week. The participants were grouped into FRP laminators and non-laminators. Linear and logistic regression was used to investigate the effects of the lamination process on lung function.Results:Laminators had a higher prevalence of chronic cough, lower pre-shift forced expiratory volume in first second (FEV1) and FEV1/force vital capacity (FVC) (-3.3% and -1.5%), lower post-shift FVC and FEV1 (-3.6% and -4.9%), and larger post-shift reduction of FVC (-2.1%) compared to non-laminators. The laminators also had higher risk of early obstructive and overall (obstructive plus restrictive) lung function impairment, and post-shift reduction of FVC >10% [odds ratio (OR) 5.98, 4.98, and 3.87, respectively). They also had higher percentages of neutrophils and lymphocytes in the induced sputum.Conclusion:Laminators should undergo regular check-ups of respiratory symptoms and lung function. Further toxicologic studies are warranted to identify the specific causal agent in the FRP lamination process.

Applicability of 2017 Global Initiative for Chronic Obstructive Lung Disease guidelines in diagnosing COPD in a tertiary care hospital

Chronic obstructive pulmonary disease (COPD) is one of the common conditions that physicians frequently diagnose and treat both in the hospital and outpatient setting. Every year, a new report is generated based on an analysis of published studies which attempts to improve the way physicians handle COPD. In 2011 and 2017, the traditional GOLD guidelines were revised, and it included exacerbation history and COPD Assessment Test (CAT) and modified Medical Research Council Dyspnoea Scale (mMRC) in diagnosis of the disease. This study we used patients’ symptoms, risk factors and exacerbation history to diagnose COPD as per 2017 guidelines and checked its accuracy by confirming with spirometry. A prospective study, in which 105 patients with history suggestive of COPD were classified according to ABCD tool, later these patients were subjected to spirometry to confirm the diagnosis of COPD and severity. The results obtained were analysed by statistical software SPSS-V.24. About 79% of the population diagnosed to have COPD by ABCD tool were confirmed using spirometry, the rest 21% either had spirometric post bronchodilator FEV1/FVC &amp;#62;0.7 or significant reversibility. CAT and mMRC test correlate with the spirometric FEV1 predicted percentage.On comparing ABCD and Spirometric grading most of them had severe airway obstruction and these people were mostly distributed in group B and D of ABCD grading. The utility of 2017 GOLD consensus in diagnosing COPD in the Indian scenario was studied. The ABCD tool of GOLD consensus will be helpful in diagnosing COPD in a resource limited setting, primary care centres were spirometry is not available.

Surgical options in suprastomal collapse-induced severe airway obstruction

PurposeA single institutions experience with various surgical options in the treatment of severe suprastomal collapse (SSC).MethodsThe study included 18 tracheostomized children with SSC treated between January 2012 and December 2018. Data included: patient demography, initial airway lesions, comorbidities, indication and age at tracheostomy, prior airway surgery, stomal demography, type of surgery, postoperative management, complications and treatment outcomes.ResultsFour techniques were used to correct SSC. The surgical choice was dependent on stoma demography and associated airway lesions. Excision was done in eight patients and rib cartilage augmentation in five. Three patients had single stage tracheal resection and anastomosis. Two patients received stomal rigidification and temporary placement of Montgomery T tube. Three patients with anterior rib graft augmentation required additional lateral tracheal wall rigidification. Three patients (two with cartilage augmentation, and one with stomal rigidification) developed minimal granulation tissue in the postoperative period. Complete SSC resolution was seen in all except two patients who had a partial response to the treatment. All patients were successful decannulated and are currently asymptomatic.ConclusionDecannulation failures may be due to severe suprastomal collapse that could be either unique or associated with obstructing laryngotracheal lesions. Therefore, it is essential to select the most appropriate surgical treatment to obtain overall favorable outcomes.

Placement of a Supraglottic Airway to Overcome Airway Obstruction When Performing Nasal Fiberoptic Intubation in Infants With Pierre Robin Sequence: A Case Series

Patients with Pierre Robin sequence present with numerous anatomical abnormalities that make mask ventilation and tracheal intubation challenging. In this case series, we describe a unique way to overcome upper airway obstruction with the placement of a supraglottic airway in 4 children with Pierre Robin sequence followed by flexible bronchoscopic nasotracheal intubation. This new approach is proven to be a successful method to overcome severe upper airway obstruction, provide continuous oxygenation, and allows nasotracheal intubation for intraoral procedures.

Prolonged (continuous) prone position ventilation in a patient with a large mediastinal mass

: We report a case of a twenty-two years old woman with a large anterior mediastinal mass admitted to the ICU with severe airway obstruction and bronchospasm after a percutaneous biopsy of the mediastinal mass and left thoracentesis. Mechanical ventilation was optimized and high dose steroid therapy, bronchodilators and sevoflurane were prescribed; severe hypoxemia persisted (PaO2/FiO2 85), therefore she was ventilated in prone position. After 12 days of mechanical ventilation, of which six of them were in continuous prone position (156 h), the patient was successfully extubated. Prone position helped to treat increased airway resistance and collapse, therefor clinicians must be aware that maintenance of spontaneous ventilation and avoidance of general anesthesia are of paramount importance to prevent cardiopulmonary collapse in patients with large anterior mediastinal masses. Prolonged continuous prone position ventilation should be considered as “rescue therapy” in such cases.

Novel Approach of Mandibular Distraction to Avoid Tracheostomy in KAT6B-related Gene Disorders

Previously, severe upper airway obstruction in patients with retrognathia and glossoptosis has been managed with tracheostomy. However, tracheostomy is associated with significant morbidity. In recent years, mandibular distraction has become an alternative management strategy in infants, but these applications have been limited to patient populations with retrognathia and glossoptosis. The authors present 2 unique cases of patients with KAT6B-related gene disorders, who present with a paradox of tongue-based airway obstruction in the absence of retrognathia. In both cases mandibular distraction osteogenesis with an obliquely oriented vector was successfully performed and both children avoided the need for tracheostomy.

Short-term condylar and glenoid fossa changes in infants with Pierre Robin sequence undergoing mandibular distraction osteogenesis

The purpose was to evaluate short-term changes in condylar and glenoid fossa morphology in infants with Pierre Robin sequence (PRS) undergoing early (age <4 months) mandibular distraction osteogenesis (MDO) for the management of severe airway obstruction. Computed tomography data from infants with PRS who had MDO were compared to those of age-matched control infants without facial skeletal dysmorphology. Surface/volume, linear, and angular measurements of the condyle and glenoid fossa were obtained and compared between infants with PRS and controls. Eleven infants with PRS met the inclusion criteria. There were five female and six male subjects with a mean age at the time of MDO of 41±32 days. Prior to MDO, PRS mandibles had a smaller condylar articulating surface area and volume than age-matched control mandibles, with a more laterally positioned condylar axis (P≤0.05). Following MDO, there were significant increases in condylar articulating surface area and volume, approaching those of normal controls, with further lateral translation of the condylar axis (P≤0.05). Condyle and glenoid fossa morphology is largely normalized following early MDO in infants with PRS. The condylar axis translates laterally as a result of MDO; this change is not observed with mandibular growth in infants without PRS.

Comparison and intervention of differences in upper airway obstruction in children with OSAS between awake and asleep

Objective:Drug induced sleep endoscopy（DISE） is a useful tool to locate the upper airway obstructions in patients with obstructive sleep apnea syndrome（OSAS）. The goal of our research was to compare the sites, degree and patterns of upper airway obstruction detected by DISE versus endoscopy in awake children. The benefit of DISE-mediated upper airway surgery in pediatric OSAS was evaluated. Method:This is a retrospective case series of children with OSAS who had adenoid hypertrophy（the area where adenoids block the postnaris ≥2/3） and tonsils ≤2 degrees（Friedman classification method） . All children underwent sleep monitoring by pulse oximeter before and after operation. DISE was performed before adenoidectomy in DISE group. If obstruction of oropharynx caused by tonsils was found, tonsillectomy was performed at the same time with adenoidectomy. The children who did not undergo DISE before operation were enrolled in the control group. Differences in the degrees and patterns of upper airway obstruction in the DISE group under wakefulness and drug induction were analyzed. Result:The study included 126 children in DISE group, and 200 children in control group. In the DISE group, 56 cases（44.4%） had grade 2 tonsils, and 70 cases（55.6%） had grade 1 tonsils. The patterns of obstruction at velum, tongue base and epiglottis were significantly different in DISE compared with awake endoscopy（P<0.05）; the patterns of obstruction at adenoid and oropharynx were the same in both techniques. There were significant differences in endoscopy scores between the lateral wall of oropharynx and the tongue base（P<0.05）. DISE revealed 57 （45.2%） cases had grade 2 obstruction in the oropharyngeal level. Among them, 44 cases （34.9%） had tonsils at 2 degrees and 13 cases （10.3%） had tonsils at 1 degrees.. There was an improvement in respiratory disturbance index（RDI） and oxygen saturation nadir in the DISE and control groups 1 year after surgery（P<0.05）, and the RDI improvement was better in the DISE group compared with controls（P=0.04）. Conclusion:DISE is an effective method to evaluate the sites and severity of upper airway obstruction in children with OSAS, which was conductive to make the upper airway personalized surgical plan for patients.

Optimize General Anesthesia for a Dystrophic Epidermolysis Bullosa Patient That Cannot Be Intubated.

Dystrophic epidermolysis bullosa (DEB) is a rare genetic skin disease characterized by blisters and ulcers on the skin and mucosa after minor friction. The risk of invasive squamous cell carcinoma on the unhealed ulcers increases with age. Tracheal intubation during general anesthesia may induce tracheal stricture due to blister formation and/or scarring in DEB patients and cause severe airway obstruction. There is no consensus for handling DEB patients' fragile mucosa and skin during general anesthesia. We report an adult DEB patient who received two operations under different general anesthesia methods. The experience from this particular patient and her response to anesthesia may provide a satisfactory guide to avoid complications and improve the outcome for DEB patients receiving general anesthesia.

&lt;p&gt;Quality of Life and Limitations in Daily Life of Stable COPD Outpatients in a Real-World Setting in Austria – Results from the CLARA Project&lt;/p&gt;

BackgroundCOPD patients suffer from respiratory symptoms and limitations in daily life. We aimed to characterize the impact of disease on overall health, daily life, and perceived well-being in COPD outpatients.MethodsWe conducted a national, cross-sectional study among pulmonologists and general practitioners (GPs). The St. George’s Respiratory Questionnaire for COPD patients (SGRQ-C) was used. Inclusion criteria were a physician’s diagnosis of COPD and age ≥40 years. Subjects with a history of lung surgery, lung cancer or COPD exacerbation within the last four weeks were excluded.ResultsSixty-seven pulmonologists and 6 GPs enrolled 1175 COPD patients. Two hundred forty-eight of those did not fulfill GOLD criteria for COPD (FEV1/FVC <0.7) and 77 were excluded due to missing data. Finally, 850 patients (62.8% men; mean age 66.2 ± 0.3 (SE) years; mean FEV1%pred. 51.5 ± 0.6 (SE)) were analyzed. Last year, 55.4% reported at least one exacerbation, and 12.7% were hospitalized for COPD exacerbation. Mean SGRQ-C total score was 43.1 ± 0.83 (SE) and mean component scores for symptoms, activity and impacts were 55.6, 55.4 and 30.5, respectively. Half of the patients (50.3%) reported not being able to do any sports and 78.7% stated that their respiratory symptoms did not allow them doing anything they would like to do. In patients with less severe COPD (FEV1pred ≥50% and non-frequent exacerbations), global health status was overrated, ie, estimated as better by the physician than by the patient, while it was underrated in more severe COPD.ConclusionIn Austria, the burden of disease in COPD outpatients tends to be underestimated in patients with milder airway obstruction and less exacerbations and overestimated in patients with more severe airway obstruction and frequent exacerbations. Our finding suggests that validated assessment of global health status might decrease these differences of perception.