Phenotypic Heterogeneity of Chronic Obstructive Pulmonary Disease

A functional definition of chronic obstructive pulmonary disease (COPD) based on airflow limitation has largely dominated the field. However, a view has emerged that COPD involves a complex array of cellular, organic, functional, and clinical events, with a growing interest in disentangling the phenotypic heterogeneity of COPD. The present review is based on the opinion of the authors, who have extensive research experience in several aspects of COPD. The starting assumption of the review is that current knowledge on the pathophysiology and clinical features of COPD allows us to classify phenotypic information in terms of the following dimensions: respiratory symptoms and health status, acute exacerbations, lung function, structural changes, local and systemic inflammation, and systemic effects. Twenty-six phenotypic traits were identified and assigned to one of the 6 dimensions. For each dimension, a summary is provided of the best evidence on the relationships among phenotypic traits, in particular among those corresponding to different dimensions, and on the relationship between these traits and relevant events in the natural history of COPD. The information has been organized graphically into a phenotypic matrix where each cell representing a pair of phenotypic traits is linked to relevant references. The information provided has the potential to increase our understanding of the heterogeneity of COPD phenotypes and help us plan future studies on aspects that are as yet unexplored.     

Skeletal Implications of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is associated with numerous comorbidities, among which osteoporosis is of high significance. Low bone mass and the occurrence of fragility fractures is a common finding in patients with COPD. Typical risk factors related directly or indirectly to these skeletal complications include systemic inflammation, tobacco smoking, vitamin D deficiency, and treatment with oral or inhaled corticosteroids. In particular, treatment with glucocorticoids appears to be a strong contributor to bone changes in COPD, but does not fully account for all skeletal complications. Additional to the effects of COPD on bone mass, there is evidence for COPD-related changes in bone microstructure and material properties. This review summarizes the clinical outcomes of low bone mass and increased fracture risk, and reports on recent observations in bone tissue and material in COPD patients.     

慢性阻塞性肺疾病与勃起功能障碍

慢性阻塞性肺疾病(COPD)不仅是肺疾病,而且是一种全身疾病,ED是COPD的肺外表现之一,随着COPD患者病情的加重,ED的发病率增加,但是COPD患者发生ED的机制至今尚未完全明确。探讨COPD患者ED的发生情况及影响因素,有助于提高COPD患者对发生ED的早期认识,预防ED的发生、发展,对改进COPD患者的生活质量具有重要意义。     

Chronic Obstructive Pulmonary Disease and Heart Failure

Chronic obstructive pulmonary disease (COPD) is commonly associated with heart failure. Individuals with COPD have a 4.5-fold greater risk of developing heart failure than those without. The sensitivity and specificity of clinical judgment in the diagnosis of heart failure in patients with COPD can be enhanced by biological markers such as B-type natriuretic peptide and N-terminal pro-B-type natriuretic peptide. Correct interpretation of imaging results (mainly echocardiographic findings) and lung function tests can also help establish the co-occurrence of both conditions. There is little evidence on the management of patients with COPD and heart failure, although treatment of COPD undeniably affects the clinical course of patients with heart failure and viceversa.     

Chronic Obstructive Pulmonary Disease History Assessment in Spain: A Multidimensional Chronic Obstructive Pulmonary Disease Evaluation. Study Methods and Organization

IntroductionThis present paper describes the method and the organization of the study known as the COPD History Assessment In SpaiN (CHAIN), whose main objective is to evaluate the long-term natural history of a chronic obstructive pulmonary disease (COPD) patient cohort from a multidimensional standpoint and to identify clinical phenotypes, in comparison with another non-COPD control cohort.Patients and methodsCHAIN is a multicenter, observational study of prospective cohorts carried out at 36 Spanish hospitals. Both cohorts will be followed-up during a 5-year study period with complete office visits every 12 months and telephone interviews every 6 months in order to evaluate exacerbations and the vital state of the subjects. The recruitment period for cases was between 15 January 2010 and 31 March 2012. At each annual visit, information will be collected on: (i) clinical aspects (socio-economic situation, anthropometric data, comorbidities, smoking, respiratory symptoms, exacerbations, quality of life, anxiety-depression scale, daily life activities, treatments); (ii) respiratory function (spirometry, blood gases, hyperinflation, diffusion, respiratory pressures); (iii) BODE index (main study variable); (iv) peripheral muscle function, and (v) blood work-up (including IgE and cardiovascular risk factors). In addition, a serum bank will be created for the future determination of biomarkers. The data of the patients are anonymized in a database with a hierarchical access control in order to guarantee secure information access. The CHAIN study will provide information about the progression of COPD and it will establish a network of researchers for future projects related with COPD.     

Chronic Obstructive Pulmonary Disease in Patients With Acute Symptomatic Pulmonary Embolism

BackgroundThe diagnosis of pulmonary embolism (PE) is often complicated by the presence of chronic obstructive pulmonary disease (COPD). Some studies have suggested that patients with PE and concomitant COPD have a worse prognosis than patients without COPD.Patients and MethodsOutpatients diagnosed with acute symptomatic PE at a university tertiary care hospital were prospectively included in the study. Clinical characteristics, time between onset of symptoms and diagnosis, and outcome were analyzed according to presence or absence of COPD. The primary endpoint was all-cause deaths at 3 months.ResultsOf 882 patients with a confirmed diagnosis of acute symptomatic PE, 8% (95% confidence interval [CI], 6%-9%) had COPD. Patients with COPD were significantly more likely to have a delay in diagnosis of more than 3 days and to have a low pretest probability of pulmonary embolism according to a standardized clinical score. The total number of deaths during 3 months of follow-up was 128 (14%; 95% CI, 12%-17%). Factors significantly associated with mortality from all causes were a history of cancer or immobilization, systolic blood pressure less than 100 mm Hg, and arterial oxyhemoglobin saturation less than 90%. COPD was significantly associated with PE-related death in the logistic regression analysis (relative risk, 2.2; 95% CI, 1.0-5.1).ConclusionsPatients with COPD and PE more often have a lower pretest probability and a longer delay in diagnosis of PE. COPD is significantly associated with PE-related death in the 3 months following diagnosis.     

Muscle Glucose Metabolism in Chronic Obstructive Pulmonary Disease Patients

IntroductionMuscle dysfunction is one of the most extensively studied manifestations of COPD. Metabolic changes in muscle are difficult to study in vivo, due to the lack of non-invasive techniques. Our aim was to evaluate metabolic activity simultaneously in various muscle groups in COPD patients.MethodsThirty-nine COPD patients and 21 controls with normal lung function, due to undergo computed axial and positron emission tomography for staging of localized lung lesions were included. After administration of 18-fluordeoxyglucose, images of 2 respiratory muscles (costal and crural diaphragm, and rectus abdominus) and 2 peripheral muscles (brachial biceps and quadriceps) were obtained, using the standard uptake value as the glucose metabolism index.ResultsStandard uptake value was higher in both portions of the diaphragm than in the other muscles of all subjects. Moreover, the crural diaphragm and rectus abdominus showed greater activity in COPD patients than in the controls (1.8±0.7 vs 1.4±0.8; and 0.78±0.2 vs 0.58±0.1; respectively, P<.05). A similar trend was observed with the quadriceps. In COPD patients, uptake in the two respiratory muscles and the quadriceps correlated directly with air trapping (r=0.388, 0.427 and 0.361, respectively, P<.05).ConclusionsThere is greater glucose uptake and metabolism in the human diaphragm compared to other muscles when the subject is at rest. Increased glucose metabolism in the respiratory muscles (with a similar trend in their quadriceps) of COPD patients is confirmed quantitatively, and is directly related to the mechanical loads confronted.