Yves Lacasse

Meta-analysis of respiratory rehabilitation in chronic obstructive pulmonary disease

BACKGROUND Respiratory rehabilitation is increasingly recognised as an important part of the management of patients with chronic obstructive pulmonary disease (COPD). The widespread application of such programmes should be preceded by evidence of directly attributable improvements in function. We assessed the effect of respiratory rehabilitation on exercise capacity and health-related quality of life (HRQL) in patients with COPD. METHODS We carried out a meta-analysis of randomised controlled trials of respiratory rehabilitation in patients with COPD that assessed functional or maximal exercise capacity, HRQL, or both. Respiratory rehabilitation was defined as exercise training (for at least 4 weeks) with or without education, psychological support, or both. The most commonly used measure for HRQL was the chronic respiratory questionnaire, in which responses were presented on a 7-point scale. The control groups received no rehabilitation. Within each trial and for each outcome an effect size was calculated; the effect sizes were then pooled by a random-effects model. The overall effect of treatment was compared with its minimum clinically important difference (MCID)--defined as the smallest difference perceived as important by the average patient. FINDINGS We included 14 trials. Significant improvements were found for all the outcomes. For two important features of HRQL, dyspnoea and mastery, the overall treatment effect was larger than the MCID: 1.0 (95% CI 0.6-1.5) and 0.8 (0.5-1.2), respectively, compared with an MCID of 0.5. For functional exercise capacity (6-min walk test), the overall effect was 55.7 m (27.8-92.8), and for maximum exercise capacity (incremental cycle ergometer test), 8.3 W (2.8-16.5). Functional exercise capacity showed heterogeneity that could not be explained by the sensitivity analyses. INTERPRETATION Respiratory rehabilitation relieves dyspnoea and improves the control over COPD. These improvements are clinically important. The value of the improvement in exercise capacity is not clear. Respiratory rehabilitation is an effective part of care in patients with COPD.

Canadian Thoracic Society recommendations for management of chronic obstructive pulmonary disease - 2007 update

Chronic obstructive pulmonary disease (COPD) is a major respiratory illness in Canada that is both preventable and treatable. Our understanding of the pathophysiology of this complex condition continues to grow and our ability to offer effective treatment to those who suffer from it has improved considerably. The purpose of the present educational initiative of the Canadian Thoracic Society (CTS) is to provide up to date information on new developments in the field so that patients with this condition will receive optimal care that is firmly based on scientific evidence. Since the previous CTS management recommendations were published in 2003, a wealth of new scientific information has become available. The implications of this new knowledge with respect to optimal clinical care have been carefully considered by the CTS Panel and the conclusions are presented in the current document. Highlights of this update include new epidemiological information on mortality and prevalence of COPD, which charts its emergence as a major health problem for women; a new section on common comorbidities in COPD; an increased emphasis on the meaningful benefits of combined pharmacological and nonpharmacological therapies; and a new discussion on the prevention of acute exacerbations. A revised stratification system for severity of airway obstruction is proposed, together with other suggestions on how best to clinically evaluate individual patients with this complex disease. The results of the largest randomized clinical trial ever undertaken in COPD have recently been published, enabling the Panel to make evidence-based recommendations on the role of modern pharmacotherapy. The Panel hopes that these new practice guidelines, which reflect a rigorous analysis of the recent literature, will assist caregivers in the diagnosis and management of this common condition.

Canadian Thoracic Society Recommendations for Management of Chronic Obstructive Pulmonary Disease – 2008 Update – Highlights for Primary Care

Chronic obstructive pulmonary disease (COPD) is a major respiratory illness in Canada that is preventable and treatable but unfortunately remains underdiagnosed. The purpose of the present article from the Canadian Thoracic Society is to provide up-to-date information so that patients with this condition receive optimal care that is firmly based on scientific evidence. Important summary messages for clinicians are derived from the more detailed Update publication and are highlighted throughout the document. Three key messages contained in the update are: use targeted screening spirometry to establish a diagnosis and initiate prompt management (including smoking cessation) of mild COPD; improve dyspnea and activity limitation in stable COPD using new evidence-based treatment algorithms; and understand the importance of preventing and managing acute exacerbations, particularly in moderate to severe disease.

Recent Advances in Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis (HP) is a pulmonary disease with symptoms of dyspnea and cough resulting from the inhalation of an allergen to which the subject has been previously sensitized. The diagnosis of HP most often relies on an array of nonspecific clinical symptoms and signs developed in an appropriate setting, with the demonstration of interstitial markings on chest radiographs, serum precipitating antibodies against offending antigens, a lymphocytic alveolitis on BAL, and/or a granulomatous reaction on lung biopsies. The current classification of HP in acute, subacute, and chronic phases is now challenged, and a set of clinical predictors has been proposed. Nonspecific interstitial pneumonitis, usual interstitial pneumonia, and bronchiolitis obliterans organizing pneumonia may be the sole histologic expression of the disease. Presumably, like in idiopathic interstitial pneumonia, acute exacerbations of chronic HP may occur without further exposure to the offending antigen. New offending antigens, such as mycobacteria causing hot tub lung and metalworking fluid HP, have recently been identified and have stimulated further research in HP.

Randomised trial of ambulatory oxygen in oxygen-dependent COPD

Long-term oxygen therapy may limit a patients ability to remain active and may be detrimental to the rehabilitation process. This study aimed to determine the effect of ambulatory oxygen on quality of life and exercise capacity in patients with chronic obstructive pulmonary disease fulfilling the usual criteria of long-term oxygen therapy. In a 1-yr, randomised, three-period, crossover trial, 24 patients (mean age 68 yrs; mean arterial partial pressure of oxygen at rest 7.1 kPa (53 mmHg)) were allocated to one of the six possible sequences generated by three interventions: 1) standard therapy (home oxygen therapy with an oxygen concentrator only); 2) standard therapy plus as-needed ambulatory oxygen; and 3) standard therapy plus ambulatory compressed air. The comparison of ambulatory oxygen versus ambulatory compressed air was double blind. The main outcomes were quality of life (Chronic Respiratory Questionnaire), exercise tolerance (6-min walk test) and daily duration of exposure to oxygen therapy. The trial was stopped prematurely after an interim analysis. On average, the patients used few ambulatory cylinders (7.5 oxygen cylinders versus 7.4 compressed air cylinders over a 3-month study period). Ambulatory oxygen had no effect on any of the outcomes. In conclusion, the current results do not support the widespread provision of ambulatory oxygen to patients with oxygen-dependent chronic obstructive pulmonary disease.

Neuromuscular electrical stimulation of the lower limbs in patients with chronic obstructive pulmonary disease.

Exercise training comprises a variety of modalities in patients with chronic obstructive pulmonary disease (COPD). In the last 10 years, neuromuscular electrical stimulation (NMES) has attracted the interests of clinicians as a novel rehabilitative approach. Because of a limited impact on ventilatory requirements and dyspnea, NMES appears as a promising alternative to general physical reconditioning in patients with advanced COPD. In this review, the technical aspects of electrostimulation, its clinical benefits in COPD, and the potential mechanisms of action have been discussed.

Natriuretic peptides and troponins in pulmonary embolism: A meta-analysis

Background: The role of biomarkers such as B-type natriuretic peptides (BNP and NT-proBNP) and troponins in risk stratification of acute pulmonary embolism (APE) is still debated. A meta-analysis was performed to assess the association between raised natriuretic peptide levels, alone or in conjunction with troponins, and all-cause and APE-related mortality, serious adverse events and echographic right ventricular dysfunction. Methods: MEDLINE and EMBASE databases were searched and conference abstracts were hand searched up to February 2008. Studies were included if a 2×2 table could be constructed based on natriuretic peptide results and at least one of the outcomes. Results: Twenty-three studies were included (1127 patients). Raised natriuretic peptide levels were significantly associated with all-cause mortality (odds ratio (OR) 6.2; 95% confidence interval (CI) 3.0 to 12.7), APE-related mortality (OR 5.0; 95% CI 2.2 to 11.5) and serious adverse events (OR 6.7; 95% CI 3.9 to 11.6), with homogeneity across studies. Among patients with raised natriuretic peptide levels, increased serum troponins were associated with a further increase in the risk of adverse outcomes. Analysis of the accuracy of natriuretic peptides in detecting right ventricular dysfunction was limited by heterogeneity across studies. BNP appeared to have better sensitivity and specificity than NT-proBNP in detecting right ventricular dysfunction. Conclusions: Raised levels of B-type natriuretic peptides identified a subset of patients with APE at higher risk of adverse outcomes. Among patients with raised natriuretic peptide levels, increased troponins were found to be an independent prognostic marker. The results of this meta-analysis may have important clinical implications in the management of APE.

A Systematic Overview of the Measurement Properties of the Chronic Respiratory Questionnaire

BACKGROUND: Assessment of health-related quality of life (HRQL) of patients with chronic lung disease has become an important aspect of many clinical investigations. The authors examined the measurement properties of a disease-specific HRQL questionnaire, the Chronic Respiratory Questionnaire (CRQ), when used by independent investigators in clinical trials and observational studies.

Postoperative outcome after coronary artery bypass grafting in chronic obstructive pulmonary disease.

BACKGROUND It is uncertain if the presence and severity of airflow obstruction in chronic obstructive pulmonary disease (COPD) is predictive of surgical morbidity and mortality after coronary artery bypass grafting (CABG). METHODS Retrospective study of patients who underwent CABG between 1998 and 2003 in a university-affiliated hospital for whom a preoperative spirometry was available. COPD was diagnosed in smokers or ex-smokers 50 years of age or older in the presence of irreversible airflow obstruction. Patients were divided into three groups depending on the spirometry: controls (forced expiratory volume in 1 s [FEV1] 80% or more, FEV1/forced vital capacity [FVC] greater than 0.7), mild to moderate COPD (FEV1 50% or more and FEV1/FVC 0.7 or less) and severe COPD (FEV1 less than 50% and FEV1/FVC 0.7 or less). RESULTS Among the 411 files studied, 322 (249 men, 68+/-8 years of age) were retained (controls, n=101; mild to moderate COPD, n=153; severe COPD, n=68). The mortality rate (3.0%, 2.6% and 0%, respectively) was comparable among the three groups. Patients with severe COPD had a slightly longer hospital stay than controls (mean difference 0.7+/-1.4 days, P<0.05). Pulmonary infections were more frequent in severe COPD (26.5%) compared with mild to moderate COPD (12.4%) and controls (12.9%), P<0.05. Atrial fibrillation tended to be more frequent in severe COPD than in the other two groups. CONCLUSION Mortality rate associated with CABG surgery is not influenced by the presence and severity of airflow obstruction in patients with COPD. The incidence of pulmonary infections and length of hospital stay were increased in patients with severe COPD.

“Incomplete Resection” in Non–Small Cell Lung Cancer: Need for a New Definition

BACKGROUND This study was designed to determine the prognostic value of positive surgical resection margin or highest nodal station sampled at thoracotomy in patients with non-small cell lung cancer. METHODS Two reviewers independently examined the surgical records and pathologic reports from a randomized trial comparing computed tomography versus mediastinoscopy for staging of lung cancer. They recorded pathologic findings at the surgical resection margin, the highest mediastinal nodal station sampled at thoracotomy, histologic type, tumor size, N status, and evidence of vascular or lymphatic invasion. These variables formed the independent variables in logistic regression models to predict recurrence. RESULTS Except for 1 patient, follow-up at 3 years for 399 included patients was complete. Significant predictors of recurrence were tumor size (odds ratio [OR], 1.2 (per centimeter); 99% CI [confidence interval], 1.1 to 1.4), and N status (compared with N0, N1: OR, 1.6; CI, 0.8 to 3.1; N2: OR, 3.2; CI, 1.4 to 7.5). Other variables, including positive surgical resection margin, did not predict early recurrence or death. CONCLUSIONS In patients with non-small cell lung cancer, surgical resection margin or highest nodal station sampled at thoracotomy that are involved by carcinoma do not predict recurrence. The current definition of incomplete resection has limited prognostic significance.