Salud Santos

Pulmonary hypertension in chronic obstructive pulmonary disease

Pulmonary hypertension is a common complication of chronic obstructive pulmonary disease (COPD). Its presence is associated with shorter survival and worse clinical evolution. In COPD, pulmonary hypertension tends to be of moderate severity and progresses slowly. However, transitory increases of pulmonary artery pressure may occur during exacerbations, exercise and sleep. Right ventricular function is only mildly impaired with preservation of the cardiac output. Structural and functional changes of pulmonary circulation are apparent at the initial stages of COPD. Recent investigations have shown endothelial dysfunction and changes in the expression of endothelium-derived mediators that regulate vascular tone and cell growth in the pulmonary arteries of patients with mild disease. Some of these changes are also present in smokers with normal lung function. Accordingly, it has been postulated that the initial event in the natural history of pulmonary hypertension in COPD could be the lesion of pulmonary endothelium by cigarette-smoke products. Long-term oxygen administration is the only treatment that slows down the progression of pulmonary hypertension in chronic obstructive pulmonary disease. Nevertheless, with this treatment pulmonary artery pressure rarely returns to normal values and the structural abnormalities of pulmonary vessels remain unaltered. Vasodilators are not recommended on the basis of their minimal clinical efficacy and because they impair pulmonary gas exchange. Recognition of the role of endothelial dysfunction in the physiopathology of pulmonary hypertension in chronic obstructive pulmonary disease opens new perspectives for the treatment of this complication.

Characterization of pulmonary vascular remodelling in smokers and patients with mild COPD

Intimal enlargement of pulmonary arteries is an early change in chronic obstructive pulmonary disease (COPD). The cellular and extracellular components that are involved in this enlargement are unknown. The present study was designed to characterize the structural changes occurring in pulmonary muscular arteries in the initial disease stages. Lung specimens from patients with moderate COPD (n=8; forced expiratory volume in one second (FEV1), 66±10% predicted) and smokers without airflow obstruction (n=7; FEV1, 86±6% pred), were investigated by histochemistry to characterize extracellular matrix proteins and by immunohistochemistry to identify intrinsic cells of the vascular wall. In both COPD patients and smokers, the majority of cells present in the enlarged intimas were stained by specific smooth muscle cell (SMC) markers. No staining with endothelial or fibroblast markers was shown. A proportion of SMCs did not stain with desmin, suggesting cellular heterogeneity in this population. Elastin was the most abundant extracellular matrix protein and collagen was seen in a lower proportion. The amount of collagen was related to the intimal thickness (p<0.001). The findings demonstrated smooth muscle cell proliferation, as well as elastin and collagen deposition, in the thickened intimas of pulmonary arteries in moderate chronic obstructive pulmonary disease patients and smokers, suggesting that these abnormalities may originate at an early stage in cigarette smoke-induced respiratory disease.

Sildenafil to improve respiratory rehabilitation outcomes in COPD: a controlled trial

Pulmonary hypertension is a serious complication of chronic obstructive pulmonary disease (COPD) that currently has no established pharmacological treatment. This study aimed to assess whether concomitant treatment with sildenafil would enhance the results of pulmonary rehabilitation in patients with COPD and increased pulmonary arterial pressure (PAP). In this double-blind, randomised controlled trial patients received 20 mg sildenafil or placebo three times daily and underwent pulmonary rehabilitation for 3 months. The primary end-point was the gain in the cycle endurance time at a constant work-rate. Secondary end-points included performance in the incremental exercise test, 6-min walk distance and quality of life. 63 patients with severe COPD and moderately increased PAP were randomised. Cycle endurance time increased by 149 s (95% CI 26–518 s) in the sildenafil group and by 169 s (95% CI 0–768 s) in the placebo group (median change difference -7 s, 95% CI -540–244 s; p=0.77). Gains in the incremental exercise test, 6-min walk distance and quality of life at the end of the study did not differ between groups. Measurements of arterial oxygenation and adverse events were similar in both groups. In patients with severe COPD and moderately increased PAP, concomitant treatment with sildenafil does not improve the results of pulmonary rehabilitation in exercise tolerance. Sildenafil did not improve respiratory rehabilitation outcomes in patients with severe COPD and moderately increased PAP http://ow.ly/lh7cb

Response to hypoxia of pulmonary arteries in chronic obstructive pulmonary disease: an in vitro study

Patients with chronic obstructive pulmonary disease (COPD) show impaired hypoxic pulmonary vasoconstriction that might contribute to abnormal gas exchange and could be related to endothelial dysfunction in pulmonary arteries. The aim of the study was to investigate the response of PA to hypoxic stimulus in vitro in COPD, and the role of endothelium-derived nitric oxide (NO) in this response. The pulmonary arteries of 25 patients who underwent lung resection were studied. Patients were divided into controls, COPD+normoxaemia (COPDN) and COPD+hypoxaemia (COPDH). Hypoxic vasoconstriction (HV) was evaluated before and after stimulation or inhibition of the endothelial release of NO, and in the presence of exogenous NO. Compared with the other groups, HV was reduced in COPDH. The magnitude of HV correlated with the oxygen tension in arterial blood. The hypoxic stimulus induced greater contraction after stimulating endothelial release of NO, whereas its inhibition practically abolished HV. Exogenous NO completely inhibited HV. Maximal relaxation induced by endothelium-dependent vasodilators correlated with the magnitude of HV. In conclusion, pulmonary arteries of patients with chronic obstructive pulmonary disease and hypoxaemia have an impaired response to hypoxic stimulus, and the endothelial release of nitric oxide modulates hypoxic vasoconstriction. The depressed response of pulmonary arteries to hypoxia may contribute to abnormal gas exchange in chronic obstructive pulmonary disease.

Serotypes and genotypes of Streptococcus pneumoniae causing pneumonia and acute exacerbations in patients with chronic obstructive pulmonary disease

OBJECTIVES This study aimed to compare the antibiotic susceptibilities, serotypes and genotypes of pneumococci causing pneumonia or acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in patients with COPD. METHODS A total of 611 pneumococci collected from 487 COPD patients with pneumonia (n = 255, 94 bacteraemic pneumonia) or AECOPD episodes (n = 356), from 2001 to 2008, were analysed. Antibiotic susceptibility was studied by microdilution. Serotypes (PCR or Quellung) and genotypes (PFGE and multilocus sequence typing) were determined. RESULTS Pneumococci isolated from AECOPD episodes were significantly more resistant to co-trimoxazole and chloramphenicol than those isolated from pneumonia episodes (39.0% versus 29.7% and 13.8% versus 8.2%, respectively, P < 0.05). Comparing serotypes of isolates causing bacteraemic pneumonia, non-bacteraemic pneumonia and AECOPD, serotypes 4, 5 and 8 were associated with bacteraemic pneumonia (P < 0.05), serotypes 1 and 3 were associated with bacteraemic and non-bacteraemic pneumonia (P < 0.05) and serotypes 16F and 11A and non-typeable pneumococci were associated with AECOPD episodes (P < 0.05). The genotypes related to serotypes 3 (Netherlands(3)-ST180 and ST260(3)), 1 (Sweden(1)-ST306), 5 (Colombia(5)-ST289) and 8 (Netherlands(8)-ST53) were isolated more frequently in pneumonia episodes (P < 0.05), whereas genotype ST30(16F) (serotype 16F) was more frequently recovered from AECOPD episodes. CONCLUSIONS In our experience, serotype 3 pneumococci (Netherlands(3)-ST180 and ST260(3) genotypes) commonly cause pneumonia and acute exacerbations in COPD patients. Pneumococci of serotypes 1 (Sweden(1)-ST306), 4 (ST247(4)), 5 (Colombia(5)-ST289) and 8 (Netherlands(8)-ST53) were more often associated with pneumonia. Non-typeable pneumococci may play an important role in acute exacerbations.

High Prevalence of Left Ventricle Diastolic Dysfunction in Severe COPD Associated with A Low Exercise Capacity: A Cross-Sectional Study

Background A subclinical left ventricle diastolic dysfunction (LVDD) has been described in patients with chronic obstructive pulmonary disease (COPD). Objectives To evaluate the prevalence of LVDD in stable severe COPD patients, to analyze its relationship with exercise capacity and to look for its possible causes (lung hyperinflation, ventricular interdependence or inflammatory mechanisms). Methods We evaluated 106 consecutive outpatients with severe COPD (FEV1 between 30–50%). Thirty-three (31%) were excluded because of previous heart disease. A pulmonary function test, a 6-minute walking test (6MWT), a Doppler echocardiography test, including diastolic dysfunction parameters, and an analysis of arterial blood gases, NT-proBNP and serum inflammatory markers (CRP, leucocytes), were performed in all patients. Results The prevalence of LVDD in severe stable COPD patients was 90% (80% type I, n=57, and 10% type II, n=7). A significant association between a lower E/A ratio (higher LVDD type I) and a lower exercise tolerance (6-minute walked distance (6MWD)) was found (r=0.29, p<0.05). The fully adjusted multivariable linear regression model demonstrated that a lower E/A ratio, a DLCO in the quartile 4th and a higher tobacco consumption were associated with a lower 6MWD (76, 57 and 0.7 metres, respectively, p<0.05). A significant correlation between E/A ratio and PaO2 was observed (r=0.26, p<0.05), but not with static lung hyperinflation, inflammation or right ventricle overload parameters. Conclusion In stable severe COPD patients, the prevalence of LVDD is high and this condition might contribute in their lower exercise tolerance. Hypoxemia could have a concomitant role in their pathogenesis.

Lung fibrotic tenascin-C upregulation is associated with other extracellular matrix proteins and induced by TGFβ1

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive parenchymal lung disease of unknown aetiology and poor prognosis, characterized by altered tissue repair and fibrosis. The extracellular matrix (ECM) is a critical component in regulating cellular homeostasis and appropriate wound healing. The aim of our study was to determine the expression profile of highlighted ECM proteins in IPF lungs.MethodsECM gene and protein expression was analyzed by cDNA microarrays, rt-PCR, immunohistochemistry and western-blot in lungs from idiopathic pulmonary fibrosis (IPF), hypersensitivity pneumonitis (HP), categorized as chronic (cHP) and subacute (saHP), and healthy lung tissue. Primary fibroblast cultures from normal subjects and fibrotic patients were studied to evaluate tenascin-C (TNC) synthesis.ResultsA total of 20 ECM proteins were upregulated and 6 proteins downregulated in IPF. TNC was almost undetected in normal lungs and significantly upregulated in fibrotic lungs (IPF and cHP) compared to saHP. Furthermore, it was located specifically in the fibroblastic foci areas of the fibrotic lung with a subepithelial gradient pattern. TNC levels were correlated with fibroblastic foci content in cHP lungs. Versican and fibronectin glycoproteins were associated with TNC, mainly in fibroblastic foci of fibrotic lungs. Fibroblasts from IPF patients constitutively synthesized higher levels of TNC than normal fibroblasts. TNC and α-sma was induced by TGF-β1 in both fibrotic and normal fibroblasts. TNC treatment of normal and fibrotic fibroblasts induced a non-significant increased α-sma mRNA.ConclusionsThe difference in ECM glycoprotein content in interstitial lung diseases could contribute to the development of lung fibrosis. The increase of TNC in interstitial areas of fibrotic activity could play a key role in the altered wound healing.

Treatment of patients with COPD and recurrent exacerbations: the role of infection and inflammation.

Exacerbations of COPD represent an important medical and health care problem. Certain susceptible patients suffer recurrent exacerbations and as a consequence have a poorer prognosis. The effects of bronchial infection, either acute or chronic, and of the inflammation characteristic of the disease itself raise the question of the possible role of antibiotics and anti-inflammatory agents in modulating the course of the disease. However, clinical guidelines base their recommendations on clinical trials that usually exclude more severe patients and patients with more comorbidities, and thus often fail to reflect the reality of clinicians attending more severe patients. In order to discuss aspects of clinical practice of relevance to pulmonologists in the treatment and prevention of recurrent exacerbations in patients with severe COPD, a panel discussion was organized involving expert pulmonologists who devote most of their professional activity to day hospital care. This article summarizes the scientific evidence currently available and the debate generated in relation to the following aspects: bacterial and viral infections, chronic bronchial infection and its treatment with cyclic oral or inhaled antibiotics, inflammatory mechanisms and their treatment, and the role of computerized tomography as a diagnostic tool in patients with severe COPD and frequent exacerbations.

A cross-sectional study to assess inhalation device handling and patient satisfaction in COPD

Delivery of inhaled medications via an inhaler device underpins the effectiveness of treatment for patients with chronic obstructive pulmonary disease (COPD). Correct inhaler technique among patients is also a predictor of achieving treatment compliance and adherence. Reporting of patient satisfaction with inhalers is therefore gaining increasing attention and is now recognized as an important patient-reported outcome in clinical trials involving patients with COPD or asthma. In this cross-sectional study, we use the validated Patient Satisfaction and Preference Questionnaire (PASAPQ) to assess the handling and satisfaction for Respimat® Soft Mist™ Inhaler (SMI) compared with the Breezhaler® dry powder inhaler (DPI) among patients with COPD in Spain. Patients were already assigned to therapy with either SPIRIVA® (tiotropium) Respimat® or with Hirobriz®/Onbrez®/Oslif® (indacaterol) Breezhaler® for at least 3 but not more than 6 months before completing the PASAPQ at a single visit to the study site. The primary endpoint of the trial was the mean total PASAPQ score. Secondary endpoints were the performance score domain of the PASAPQ, the convenience score domain of the PASAPQ, and the overall satisfaction score of the PASAPQ. For the primary endpoint, the mean PASAPQ total score in the Respimat® and Breezhaler® groups was 80.7 and 79.9, respectively (difference of 0.8, 95% confidence interval [CI] −2.9 to 4.5; P=0.67). The mean total performance scores were 82.5 and 78.2 (difference of 4.3, 95% CI −0.3 to 8.9; P=0.06), and the mean total convenience scores were 78.6 and 81.9 (difference of −3.3, 95% CI −7.0 to 0.4; P=0.08) for the Respimat® and Breezhaler® groups, respectively. Patients gave the Respimat® SMI and the Breezhaler® DPI overall satisfaction PASAPQ scores of 6.0 and 5.9, respectively, which shows that patients were satisfied with these inhalers.

Some pneumococcal serotypes are more frequently associated with relapses of acute exacerbations in COPD patients.

Objectives To analyze the role of the capsular type in pneumococci causing relapse and reinfection episodes of acute exacerbation in COPD patients. Methods A total of 79 patients with 116 recurrent episodes of acute exacerbations caused by S. pneumoniae were included into this study (1995–2010). A relapse episode was considered when two consecutive episodes were caused by the same strain (identical serotype and genotype); otherwise it was considered reinfection. Antimicrobial susceptibility testing (microdilution), serotyping (PCR, Quellung) and molecular typing (PFGE/MLST) were performed. Results Among 116 recurrent episodes, 81 (69.8%) were reinfections, caused by the acquisition of a new pneumococcus, and 35 (30.2%) were relapses, caused by a pre-existing strain. Four serotypes (9V, 19F, 15A and 11A) caused the majority (60.0%) of relapses. When serotypes causing relapses and reinfection were compared, only two serotypes were associated with relapses: 9V (OR 8.0; 95% CI, 1.34–85.59) and 19F (OR 16.1; 95% CI, 1.84–767.20). Pneumococci isolated from relapses were more resistant to antimicrobials than those isolated from the reinfection episodes: penicillin (74.3% vs. 34.6%, p<0.001), ciprofloxacin (25.7% vs. 9.9%, p<0.027), levofloxacin (22.9% vs. 7.4%, p = 0.029), and co-trimoxazole (54.3% vs. 25.9%, p<0.001). Conclusions Although the acquisition of a new S. pneumoniae strain was the most frequent cause of recurrences, a third of the recurrent episodes were caused by a pre-existing strain. These relapse episodes were mainly caused by serotypes 9V and 19F, suggesting an important role for capsular type.