Clinical, functional and inflammatory characteristics in patients with paucigranulocytic stable asthma: Comparison with different sputum phenotypes

BACKGROUND

According to induced sputum cell count, four different asthma phenotypes have been recognized (eosinophilic, neutrophilic, mixed and paucigranulocytic). The aim of this study was to detect functional and inflammatory characteristics of patients with paucigranulocytic asthma.

METHODS

A total of 240 asthmatic patients were categorized into the four phenotypes according to cell counts in induced sputum. All patients underwent pulmonary function tests, and measurement of fraction of exhaled nitric oxide (FeNO). The levels of IL-8, IL-13 and eosinophilic cationic protein (ECP) were also measured in sputum supernatant. Treatment, asthma control and the presence of severe refractory asthma (SRA) were also recorded.

RESULTS

Patients were categorized into the four phenotypes as follows: eosinophilic (40%), mixed (6.7%), neutrophilic (5.4%) and paucigranulocytic (47.9%). Although asthma control test did not differ between groups (P=.288), patients with paucigranulocytic asthma had better lung function (FEV₁ % pred) [median (IQR): 71.5 (59.0-88.75) vs 69.0 (59.0-77.6) vs 68.0 (60.0-85.5) vs 80.5 (69.7-95.0), P=.009] for eosinophilic, mixed, neutrophilic and paucigranulocytic asthma, respectively, P=.009). SRA occurred more frequently in the eosinophilic and mixed phenotype (41.6% and 43.7%, respectively) and less frequently in the neutrophilic and paucigranulocytic phenotype (25% and 21.7%, respectively, P=.01). FeNO, ECP and IL-8 were all low in the paucigranulocytic, whereas as expected FeNO and ECP were higher in eosinophilic and mixed asthma, while IL-8 was higher in patients with neutrophilic and mixed asthma (P<.001 for all comparisons). Interestingly, 14.8% of patients with paucigranulocytic asthma had poor asthma control.

CONCLUSION

Paucigranulocytic asthma most likely represents a "benign" asthma phenotype, related to a good response to treatment, rather than a "true" phenotype of asthma. However, paucigranulocytic patients that remain not well controlled despite optimal treatment represent an asthmatic population that requires further study for potential novel targeted interventions.

The role of non-invasive modalities for assessing inflammation in patients with non-cystic fibrosis bronchiectasis

INTRODUCTION

Bronchiectasis is a heterogeneous entity, taking into account clinical characteristics, inflammatory response, effectiveness of treatment and frequency of exacerbations. In stable state non-cystic fibrosis (non-CF) bronchiectasis, little is known about non-invasive techniques used for evaluating airway inflammation in obstructive airway diseases.

OBJECTIVES

We sought to evaluate the associations between induced sputum and clinical/radiologic characteristics, and the differences between biomarkers expressing Th1 and Th2 response in patients with non-CF bronchiectasis and to compare our findings with a previously studied population of patients with asthma and COPD.

METHODS

We evaluated prospectively collected data from subjects with bronchiectasis. Comparisons were made between clinical, radiographic and physiologic characteristics, as well as induced sputum markers using appropriate statistical tools. We compared the levels of sputum markers with those of a previously studied cohort of asthma and COPD patients.

RESULTS

We enrolled 40 subjects (21men, mean age 63.5yrs) with bronchiectasis. Fifteen subjects (37.5%) had a neutrophilic phenotype, 7 (17.5%) had an eosinophilic phenotype, 3 (12.5%) had a mixed neutrophilic-eosinophilic phenotype and 15 (37.5%) had a paucigranulocytic phenotype. Subjects with sputum neutrophilia had more severe bronchiectasis in HRCT and higher levels of IL-8 in sputum, whereas subjects with eosinophilia had higher levels of FeNO, greater bronchodilator reversibility and higher sputum IL-13. Sputum IL-8 levels were higher in subjects exhibiting frequent exacerbations and correlated with neutrophils in sputum (r=0.799), the extent of bronchiectasis in HRCT (r=0.765) and post-bronchodilator FEV₁ (r=-0.416). Sputum IL-13 levels correlated with sputum eosinophils (r=0.656) and bronchodilator reversibility (r=0.441). Neutrophilic bronchiectasis exhibited comparable IL-8 levels to COPD, whereas eosinophilic bronchiectasis showed significantly lower IL-13 levels compared to asthma.

CONCLUSIONS

Sputum cell counts and IL-8 and IL-13 correlate with distinct clinical and functional measurements of disease severity and therefore may have a role for non-invasively assessing inflammation in non-cystic fibrosis bronchiectasis.

Serum periostin in patients hospitalized for COPD exacerbations

Serum periostin has been proposed as a surrogate biomarker of Th2 inflammatory response in patients with asthma, but its predictive role in hospitalized patients with COPD has not been evaluated. The aim of the present observational prospective cohort study was to evaluate the possible role of serum periostin as predictor of outcome in COPD patients hospitalized for AECOPD. Serum periostin was measured on admission and at discharge in patients admitted to the hospital for a COPD exacerbation. Patients were followed-up for 1year for future exacerbations, hospitalizations and mortality. 155 consecutive patients admitted to the hospital for AECOPD were included to the study. Periostin levels on admission were elevated compared to discharge [34.7 (25.2-52.2) vs. 25.9 (17.4-41.0) ng/mL, p=0.003], but serum periostin levels did not differ between patients with or without prolonged hospitalization, or those who required non-invasive ventilation, intubation, or died during hospitalization. Frequent exacerbators had higher serum periostin levels at the time of discharge compared to non-frequent exacerbators [37.9 (26.6, 64.5) vs. 23.9 (16.2, 37.9), p<0.001]. Periostin levels above the median value (25ng/mL) were not related to the time of next exacerbation, time of next COPD hospitalization, (p=0.858) or time to death. The role of serum periostin levels as a predictive biomarker of future risk in hospitalized patients with COPD is of limited value.

Direct and Indirect Costs of Asthma Management in Greece: An Expert Panel Approach

OBJECTIVE

Asthma is a major cause of morbidity and mortality and is associated with significant economic burden worldwide. The objectives of this study were to map current resource use associated with the disease management and to estimate the annual direct and indirect costs per adult patient with asthma.

METHODS

A Delphi panel with seven leading pulmonologists was conducted. A semistructured questionnaire was developed to elicit data on resource use and treatment patterns. Unit costs from official, published sources were subsequently assigned to resource use to estimate direct medical costs. Indirect costs were estimated as number of work loss days. Cost base year was 2015, and the perspective adopted was that of the National Organization of Health Care Services Provision, as well as the societal.

RESULTS

Patients with asthma are mainly managed by pulmonologists (71.4%) and secondarily by general practitioners and internists (28.6%). The annual cost of managing exacerbations was estimated at €273.1, while maintenance costs were estimated at €1,100.2 per year. Total costs of managing asthma per patient per year were estimated at €2,281.8, 64.4% of which represented direct medical costs. Of the direct costs, pharmaceutical treatment was the key driver, accounting for 63.9 and 41.2% of direct and total costs, respectively. Direct non-medical costs (patient travel and waiting time) were estimated at €152.3. Indirect costs accounted for 28.9% of total costs.

CONCLUSION

Asthma is a chronic condition, the management of which constrains the already limited Greek health care resources. The increasing prevalence of the disease raises concerns as it could translate per patient costs into a significant burden for the Greek health care system. Thus, the prevention, self-management, and improved quality of care for asthma should find a place in the health policy agenda in Greece.

Effect of pulmonary rehabilitation on tidal expiratory flow limitation at rest and during exercise in COPD patients

We hypothesized that severe COPD patients who present with the disadvantageous phenomenon of Expiratory Flow Limitation (EFL) may benefit as COPD patients without EFL do after implementation of a Pulmonary Rehabilitation (PR) program. Forty-two stable COPD patients were studied at rest and during exercise. EFL and dynamic hyperinflation (DH) were documented using the negative expiratory pressure (NEP) technique and inspiratory capacity (IC) maneuvers, respectively. Patient centered outcomes were evaluated by the Saint-George's Respiratory Questionnaire (SGRQ) and the mMRC dyspnea scale. Before PR, 16 patients presented with EFL at rest and/or during exercise. After PR, EFL was abolished in 15 out of those 16 EFL patients who exhibited a significant increase in IC values. These were mainly accomplished through a modification of the breathing pattern. In the 26 NFL patients no increase was noted in their IC or a modification of their breathing pattern. However, both NFL and EFL COPD patients improved exercise capacity and patients centered outcomes undergoing the same PR program.

Temporal evolution of thoracocentesis-induced changes in spirometry and respiratory muscle pressures

BACKGROUND

Several studies investigated the effects of thoracocentesis on aspects of respiratory function without generally ensuring absence of coexistent lung pathology or homogeneity in initial size of the effusion.

METHODS

We studied 90 patients aged 61.6±15.9 years (mean±SD) separated into a group A with small-sized or medium-sized effusion (A=56 patients) and a group B with large and massive one (B=34 patients). There was no significant lung lesion or cardiovascular pathology. The basic spirometric parameters and maximal respiratory pressures were recorded on three instances: just before thoracocentesis (T1), 30 min after completion of the procedure (T2) and after 48 hours (T3).

RESULTS

At T2 vs T1, groups A and B respectively presented significant change (mean±SD) (increase) in forced vital capacity (FVC) of 0.071±0.232 and 0.139±0.224 L, in forced expiratory volume in 1 s (FEV₁) of 0.127±0.231 and 0.201±0.192 L, in FEV₁/FVC of 2.8% and 4.9%, in peak expiratory flow rate (PEFR) of 0.342±0.482 and 0.383±0.425 L/s, in maximal expiratory pressure (MEP) of 0.049±0.037 and 0.049±0.039 kPa and in maximal inspiratory pressure (MIP) of 0.040±0.041 kPa only in group A while decrease in MIP with significant change of 0.055±0.051 kPa in group B. At T3 vs T2 in groups A and B, there was significant change (decrease) in FEV₁/FVC of 2.7% and 4.6% as well as significant change (increase) in MIP of 0.036±0.046 and 0.115±0.060 and in MEP of 0.049±0.043 and 0.070±0.048 kPa.

CONCLUSIONS

Thoracocentesis is associated with progressive-small relative to the volume of fluid removed-increases in lung volumes. In larger effusions at T2, a transient decrease in MIP is observed presumably due to temporary geometric distortion of the diaphragm immediately after fluid removal.

Vascular Biomarkers in Asthma and COPD

Bronchial asthma and chronic obstructive pulmonary disease (COPD) remain a global health problem with significant morbidity and mortality. The changes in bronchial microvasculature that occurin asthma and COPD contribute to airway wall remodeling. Angiogenesis seems to be more prevalent in asthma and vasodilatation seemsmore relevant in COPD while vascular leak is present in both diseases. Recently, there has been increased interest in the vascular component of airway remodeling in chronic bronchial inflammation of asthma and COPD although its role in the progression of the diseases has not been fully elucidated. Various cells andmediators are involved in the vascular remodeling in asthma and COPD while proinflammatory cytokines and growth factors exert angiogenic and antiangiogenic effects. Vascular endothelial growth factor (VEGF) is a key regulator of blood vessel growth mainly in asthma but also in COPD. In asthmatic airways VEGF promotes proliferation and differentiation of endothelial cells and induces vascular leakage and permeability. It has also been involved in enhanced allergic sensitization, upregulated subsequent T-helper-2 type inflammatory responses, chemotaxis for monocytes and eosinophils, and airway oedema. Impaired VEGF signaling has been associated with emphysema in animal models. Studies on lung biopsies have shown a decreasing effect of anti-asthma drugs to the vascular component of airway remodeling. There is less available evidence on the effect of the currently used drugs on airway microvascular network in COPD. This review article explores the current knowledge regarding vascular biomarkers in asthma and COPD as well as the therapeutic implications of these mediators.

Severe asthma: anti-IgE or anti-IL-5?

Severe asthma is a discrete clinical entity characterised by recurrent exacerbations, reduced quality of life and poor asthma control as ordinary treatment regimens remain inadequate. Difficulty in managing severe asthma derives partly from the multiple existing phenotypes and our inability to recognise them. Though the exact pathogenetic pathway of severe allergic asthma remains unclear, it is known that numerous inflammatory cells and cytokines are involved, and eosinophils represent a key inflammatory cell mediator. Anti-IgE (omalizumab) and anti-IL-5 (mepolizumab) antibodies are biological agents that interfere in different steps of the Th2 inflammatory cascade and are licensed in severe asthma. Both exhibit a favourable clinical outcome as they reduce exacerbation rate and improve asthma control and quality of life, while mepolizumab also induces an oral steroid sparing effect. Nevertheless, it is still questionable which agent is more suitable in the management of severe allergic asthma since no comparable studies have been conducted. Omalizumab's established effectiveness in clinical practice over a long period is complemented by a beneficial effect on airway remodelling process mediated mainly through its impact on eosinophils and other parameters strongly related to eosinophilic inflammation. However, it is possible that mepolizumab through nearly depleting eosinophils could have a similar effect on airway remodelling. Moreover, to date, markers indicative of the patient population responding to each treatment are unavailable although baseline eosinophils and exacerbation rate in the previous year demonstrate a predictive value regarding anti-IL-5 therapy effectiveness. On the other hand, a better therapeutic response for omalizumab has been observed when low forced expiratory volume in 1 sec, high-dose inhaled corticosteroids and increased IgE concentrations are present. Consequently, conclusions are not yet safe to be drawn based on existing knowledge, and additional research is necessary to unravel the remaining issues for the severe asthmatic population.

Activin A and follistatin in patients with asthma. Does severity make the difference?

BACKGROUND AND OBJECTIVE

Activin A is a pleiotropic cytokine holding a fundamental role in inflammation and tissue remodelling. Follistatin can modulate the bioactivity of activin. We aimed to measure activin A and follistatin in sputum supernatants and bronchoalveolar lavage (BAL) of asthmatic patients and to determine the possible associations with severity as well as with inflammatory and remodelling indices.

METHODS

A total of 58 asthmatic patients (33 with severe refractory asthma (SRA)) and 10 healthy controls underwent sputum induction for % cells, activin A, follistatin, eosinophilic cationic protein (ECP), transforming growth factor beta 1 (TGF-β1), IL-13 and IL-8 measurements. In 22 asthmatic patients, BAL and bronchial biopsies were also performed for the assessment of the above-mentioned variables, measurement of remodelling indices and immunostaining for different activin A receptors.

RESULTS

Sputum activin A (pg/mL) was higher in patients with SRA (median (interquartile ranges): 76 (33-185)) compared to mild-to-moderate asthma (44 (18-84); P = 0.005), whereas follistatin did not differ between the two groups. BAL activin A (pg/mL) was higher in patients with SRA compared to those with mild-to-moderate disease. A significant association was observed between activin A and TGF-β1, eosinophils in sputum and/or in BAL, while reticular basement membrane (RBM) thickness was significantly associated with BAL activin levels only. No difference in immunostaining for activin receptor type IB was observed between patients with SRA and those with mild-to-moderate asthma.

CONCLUSION

Sputum and BAL levels of activin A are higher in SRA. The association of activin A with TGF-β1, eosinophils and RBM thickness may indicate a role of this cytokine in the inflammatory and remodelling process in SRA.

Predictors of future exacerbation risk in patients with asthma

OBJECTIVES

Although modern treatment of asthma improves asthma control, some patients still experience exacerbations. The aim of the present study was to detect predictors of asthmatic exacerbations Methods: We included patients with asthma followed up in asthma clinics of 2 tertiary University hospitals. Demographic and functional characteristics, levels of exhaled NO, and inflammatory biomarkers (IL-13, ΕCP και IL-8) and cell counts in induced sputum were recorded at baseline. Measurements were performed with the patients in stability and were considered as their personal best. Patients received optimal treatment with good compliance and were followed up for 1 year for asthma exacerbations occurrence. Evaluation of the effect of recorded parameters on asthma exacerbations was performed with univariate and multivariate Poisson regression analysis.

RESULTS

171 patients (118 female) with bronchial asthma (mean age 51.6 ± 13.2 years) were included in the study. The mean number of exacerbations in 1 year of follow up was 0.4 ± 0.8 while the majority of patients (71.9%) did not experience any exacerbation. In multivariate Poisson Regression analysis only 3 characteristics were predictors of future exacerbations: FEV1 [IRR(95% CI)], [0.970(0.954-0.987)], p = 0.001, high BMI [1.078(1.030-1.129)], p = 0.001, and the need for permanent treatment with oral corticosteroids for asthma control maintenance [2.542(1.083-5.964)], p = 0.032 CONCLUSION: Optimal guideline-based asthma management results in minimal occurrence of exacerbations in the majority of patients. Predictors of exacerbations are low FEV1 levels in stability, high BMI and the need for permanent treatment with oral corticosteroids.

Non CF-bronchiectasis: Aetiologic approach, clinical, radiological, microbiological and functional profile in 277 patients

BACKGROUND AND OBJECTIVES

Non-Cystic Fibrosis (CF) bronchiectasis is common in Greece but little attention has been paid to the investigation of its aetiology, clinical, radiological, microbiological and lung function profile.

METHODS

We prospectively evaluated patients with non-CF bronchiectasis confirmed by high resolution computed tomography (HRCT) of the chest. Aetiology, clinical data, radiology score, microbiological profile and lung function were investigated.

RESULTS

We evaluated 277 patients (170 women) with bronchiectasis (mean age: 60.5 ± 16 years), 64% of them being non-smokers. Post-infectious (25.2%) and past tuberculosis (TB) (22.3%) were the most commonly identified underlying conditions, while no cause was found in 34% of the patients. The main symptoms were cough (82%), mucopurulent sputum (80%), dyspnea (60%) and haemoptysis (37%). Mean duration of symptoms was 9.7 (SD 10.7) years. Infectious exacerbations were observed in 67.5% of the patients with a mean frequency of 2.3 (SD 1.4) per year. The most frequent lung function pattern was the obstructive (43.1%) while 38% of the patients had normal spirometry. Pseudomonas aeruginosa was the most common pathogen yielded in sputum cultures (43%) followed by Haemophilus influenzae (12.6%). Patients with P. aeruginosa had a more long-standing disease and worse lung function. Radiological severity of the disease was mainly related to impaired lung function, P. aeruginosa isolation in sputum and frequent exacerbations.

CONCLUSION

Data indicate that in Greece, "past" tuberculosis remains an important cause of bronchiectasis. P. aeruginosa was the predominant pathogen in the airways, associated with disease severity, while the most common lung function impairment was obstruction.

Sputum interleukin-13 as a biomarker for the evaluation of asthma control

BACKGROUND

Asthma control refers to the extent to which the manifestations of asthma have been reduced or eradicated by treatment. Interleukin-13 (IL-13) has a central role in Th2 response and serves as a possible therapeutic target in uncontrolled asthma. Fraction of exhaled nitric oxide (FeNO) and sputum eosinophils have modest performance in the evaluation of asthma control.

OBJECTIVE

To assess the diagnostic performance of sputum IL-13 for the evaluation of asthma control and furthermore to investigate the performance of sputum eosinophils and FeNO.

METHODS

One hundred and seventy patients with asthma were studied. All subjects underwent assessment of asthma control by asthma control test (ACT), lung function tests, FeNO measurement and sputum induction for cell count identification and IL-13 measurement in supernatants.

RESULTS

IL-13 (pg/mL) levels in sputum supernatant differed significantly among patients with well-controlled asthma and those with not well-controlled asthma [median IQR 78 (66-102) vs. 213 (180-265), P < 0.001]. Receiver operating characteristic (ROC) analysis showed that, for the whole study population, the diagnostic performance of IL-13 was superior to both sputum eosinophils and FeNO levels [area under the curve (AUC) 0.92, 95% CI 0.87 to 0.95 vs. AUC 0.65, 95% CI 0.58 to 0.72 vs. AUC 0.65, 95% CI 0.55 to 0.72, respectively].

CONCLUSION

The diagnostic performance of sputum IL-13 was superior to both sputum eosinophils and FeNO levels for the identification of well-controlled asthma. Sputum IL-13 levels could serve as a useful biomarker for asthma control assessment.

Persistent airflow obstruction in patients with asthma: Characteristics of a distinct clinical phenotype

BACKGROUND

Some patients with asthma present persistent airflow limitation but their clinical and inflammatory characteristics have not been extensively described. In this study we aimed to identify differences in the clinical, functional and inflammatory characteristics between patients with asthma with and without persistent airflow obstruction.

METHODS

Patients (n = 170) were consecutively recruited from two tertiary Asthma Clinics. Patients' demographics, pulmonary function tests, inflammatory cells in induced sputum, bronchial hyperresponsiveness (BHR, PD15 to methacholine) and treatment regimens were recorded.

RESULTS

Sixty patients (35.3%) presented persistent airflow obstruction. Besides differences in lung function, patients with persistent obstruction presented, lower methacholine PD20, higher exhaled NO, and higher eosinophil and neutrophil counts in induced sputum. The majority (71.7%) of the patients with persistent obstruction fulfilled the ATS criteria for severe refractory asthma (SRA), in contrast to 4.5% in the group without persistent obstruction. A cluster analysis identified three clinically relevant clusters: Cluster 1 (n = 56, not related to persistent airflow obstruction) included non-atopic patients, who did not receive high-dose ICS without SRA; Cluster 2 (n = 53, related to persistent airflow obstruction) included atopic patients, receiving high-dose ICS and/or oral CS, fulfilling SRA criteria; Cluster 3 (n = 61, not related to persistent airflow obstruction) included atopic patients not receiving high-dose ICS, without SRA.

CONCLUSIONS

Asthma patients with persistent airflow obstruction present a distinct asthma phenotype, with significant differences in clinical, functional and inflammatory characteristics compared to patients without fixed airway obstruction. These patients present more often severe refractory asthma and require more intense treatment.

Sputum and BAL Clara cell secretory protein and surfactant protein D levels in asthma

Clara cell secretory protein (CC16) is associated with Th2 modulation. Surfactant protein D (SPD) plays an important role in surfactant homeostasis and eosinophil chemotaxis. We measured CC16 and SPD in sputum supernatants of 84 asthmatic patients and 12 healthy controls. In 22 asthmatics, we additionally measured CC16 and SPD levels in BAL and assessed smooth muscle area (SMA), reticular basement membrane (RBM) thickness, and epithelial detachment (ED) in bronchial biopsies. Induced sputum CC16 and SPD were significantly higher in patients with severe asthma (SRA) compared to mild-moderate and healthy controls. BAL CC16 and SPD levels were also higher in SRA compared to mild-moderate asthma. CC16 BAL levels correlated with ED, while SPD BAL levels correlated with SMA and RBM. Severity represented a significant covariate for these associations. CC16 and SPD levels are upregulated in SRA and correlate with remodeling indices, suggesting a possible role of these biomarkers in the remodeling process.

Low interleukin (IL)-18 levels in sputum supernatants of patients with severe refractory asthma

BACKGROUND

Severe refractory asthma (SRA) is characterized by persistent asthma symptoms, amplified airway inflammation despite treatment with high dose inhaled steroids and increased airway bacterial colonization. Interleukin (IL)-18 is a pleiotropic pro-inflammatory cytokine that modulates airway inflammation. Furthermore, as a product of the inflammasome, IL-18 is involved in host defence against viral and bacterial stimuli by modulating the immune response.

OBJECTIVE

To determine IL-18 levels in sputum supernatants of patients with asthma and to investigate whether underlying severity affects its levels. Furthermore, possible associations with atopy and mediators and cells involved in the inflammatory process of the airways were examined.

METHODS

Forty-five patients with mild intermittent asthma (21 smokers) and 18 patients with SRA in stable state were studied. All subjects underwent lung function tests, skin prick tests, and sputum induction for cell count identification. IL-18 and ECP levels were measured in sputum supernatants. Furthermore, sputum samples were examined for the commonest respiratory pathogens and viruses by real time polymerase chain reaction (RT-PCR).

RESULTS

Patients with SRA had significantly lower IL-18 levels in sputum supernatants compared to mild asthmatics (p < 0.001). Twelve out of eighteen patients with SRA were colonized by viruses and/or bacterial pathogens. IL-18 levels correlated with the percentage of macrophages (r = 0.635, p = 0.026) and inversely correlated with the percentage of neutrophils in sputum (r = -0.715, p = 0.009). No correlations were found between IL-18, ECP and the percentage of eosinophils in the sputum of SRA.

CONCLUSIONS

In SRA IL-18 is possibly involved in chronic airway inflammation through an eosinophil independent pathway. The decreased levels of IL-18 in SRA support the hypothesis of deregulated inflammasome activation, justifying the susceptibility of these patients for bacterial colonization or infection.

Angiopoietins 1 and 2 in sputum supernatant of optimally treated asthmatics: the effect of smoking

BACKGROUND

Angiopoietin-1 (Ang-1) is an essential mediator of angiogenesis by establishing vascular integrity, whereas angiopoietin-2 (Ang-2) acts as its natural inhibitor.

OBJECTIVE

We aimed to determine the levels of angiopoietins in sputum supernatants of patients with optimally treated asthma and to investigate whether smoking represents a significant covariate on the above possible processes.

METHODS

Eighty-seven patients with asthma (42 smokers) and 28 healthy subjects (14 smokers) were studied. All subjects underwent lung function tests, bronchial hyper-responsiveness assessment and sputum induction for cell count identification and measurement of Ang-1, Ang-2, vascular endothelial growth factor, TGF-β1, MMP-2, IL-13, Eosinophilic cationic protein and IL-8 in supernatants. Airway vascular permeability (AVP) index was also assessed.

RESULTS

Ang-1 (ng/mL) levels were significantly higher in patients with asthma compared to normal subjects. Smoking significantly increased Ang-1 levels [median, interquartile ranges 24 (13-37) in smoking asthmatics vs 10 (7-14) in nonsmoking asthmatics vs 5·3 (3·7-6·5) and 4·6 (3·8-5·7) in healthy smokers and nonsmokers, respectively, P < 0·001]. Similar results were observed for Ang-2 (pg/mL) [168 (132-203) vs 124 (82-152) vs 94 (78-113) vs 100 (96-108), respectively, P < 0·001]. Regression analysis in the whole study population showed a significant negative association for Ang-1, with AVP index, and MMP-2. Smoking was a significant covariate for both Ang-1 and Ang-2 in asthmatic patients.

CONCLUSIONS

Ang-1 and Ang-2 levels are upregulated in patients with optimally treated asthma. Our data support a possible role for smoking in the angiogenetic process in asthma.

Increased levels of osteopontin in sputum supernatant in patients with COPD

BACKGROUND

Osteopontin (OPN) is a phosphorylated acidic glycoprotein that can function as both an extracellular matrix molecule and a cytokine. Published data support that OPN is upregulated in surgical lung tissue samples of patients with COPD. The aim of this study was to determine the levels of OPN in sputum supernatants of patients with COPD and to investigate possible associations with mediators and cells involved in the inflammatory and remodeling process as well as with the extent of emphysema.

METHODS

Seventy-seven patients with COPD and 40 healthy subjects (20 smokers) were studied. All subjects underwent lung function tests, sputum induction for cell count identification, and OPN, transforming growth factor-β1, matrix metalloproteinase (MMP)-2, IL-8, and leukotriene-4 measurement in sputum supernatants. High-resolution CT (HRCT) scan of the chest was performed for quantification of emphysema.

RESULTS

OPN levels (pg/mL) were significantly higher in patients with COPD compared with healthy smokers and nonsmokers (median [interquartile range], 1,340 [601, 6,227] vs 101 [77, 110] vs 68 [50, 89], respectively; P < .001). Regression analysis showed a significant association between OPN and sputum neutrophils, IL-8, MMP-2, and the extent of emphysema. The associations previously listed were not observed in healthy subjects.

CONCLUSIONS

OPN levels are higher in patients with COPD compared with healthy subjects. OPN may play a role in the neutrophilic inflammation and in the pathogenesis of emphysema.

Heart rate recovery post 6-minute walking test in obstructive sleep apnea: cycle ergometry versus 6-minute walking test in OSA patients

PURPOSE

To examine the clinical usefulness of heart rate recovery (HRR) post 6-minute walking test (6MWT) as a simple marker of cardiovascular risk in obstructive sleep apnea (OSA) patients in comparison to HRR post cycle ergometry, the validated and more sophisticated protocol.

METHODS

Seventy-four participants underwent full overnight polysomnography, cycle ergometry and 6MWT. The HRR at 1, 2 and 3 min (HRR-1, HRR-2 and HRR-3) 6MWT was compared to HRR at 1, 2, and 3 min post cycle ergometry in normal subjects and in moderate and severe OSA patients before and after 6-month CPAP treatment.

RESULTS

The HRR-1, HRR-2 and HRR-3 in 6MWT were significantly different between normal, moderate and severe OSA patients with higher rates achieved in normal. The higher the severity of OSA the lower the HRR was. There were also no differences found between work rate and distance walked during cycle ergometry or 6MWT, respectively, concerning normal, moderate and severe OSA patients. Heart rate recovery was further associated with minimum saturation of oxygen during sleep independently of the duration of apnea episodes of BMI and ESS. The treatment with CPAP had a beneficial effect on HRR both post-6MWT and post cycle ergometry.

CONCLUSIONS

Autonomic nervous system dysfunction in OSA can be found even with submaximal exertion. Heart rate recovery post-6MWT, such as HRR post cycle ergometry, was significantly impaired in OSA patients in comparison to normals and was favorably influenced from CPAP treatment. Furthermore, it was found to be more sensitive compared with distance walked in 6MWT in discriminating severity of OSA. The HRR post-6MWT was found to be an easily measured and reliable marker of OSA severity both before and after CPAP treatment.