Pulmonary arterial enlargement and acute exacerbations of COPD

Comparison of CT-Determined Pulmonary Artery Diameter, Aortic Diameter, and Their Ratio in Healthy and Diverse Clinical Conditions

BACKGROUND

The main pulmonary artery diameter (mPA), aortic diameter (Ao), and the mPA/Ao ratio, easily measured using chest computed tomography (CT), provide information that enables the diagnosis and evaluation of cardiopulmonary diseases. Here, we used CT to determine the sex- and age-specific distribution of normal reference values for mPA, Ao, and mPA/Ao ratio in an adult Korean population.

METHODS

Data from non-contrast, ECG-gated, coronary-calcium-scoring CT images of 2,547 individuals who visited the Health Screening Center of the Severance Hospital were analyzed. Healthy individuals (n = 813) included those who do not have hypertension, diabetes, asthma, obstructive lung disease, ischemic heart disease, stroke, smoking, obesity, and abnormal CT findings. Both mPA and Ao were measured at the level of bifurcation of the main pulmonary artery.

RESULTS

The mean mPA and Ao were 25.9 mm and 30.0 mm in healthy participants, respectively, while the mean mPA/Ao ratio was 0.87. Medical conditions associated with a larger mPA were male, obesity, smoking history, hypertension, and diabetes. A larger mPA/Ao ratio was associated with female, the obese, non-smoker, normotensive, and normal serum level of lipids, while a smaller mPA/Ao ratio was associated with older age. In healthy individuals, the 90th percentile sex-specific mPA, Ao, and mPA/Ao ratio were, 31.3 mm (95% CI 29.9-32.2), 36.8 mm (95% CI 35.7-37.5), and 1.05 (95% CI 0.99-1.07) in males, and 29.6 mm (95% CI 29.1-30.2), 34.5 mm (95% CI 34.1-34.9), and 1.03 (95% CI 1.02-1.06) in females, respectively.

CONCLUSION

In the Korean population, the mean mPA reference values in male and female were 26.5 mm and 25.8 mm, respectively, while the mean mPA/Ao ratio was 0.87. These values were influenced by a variety of underlying medical conditions.

Multivariate analysis in thoracic research

Multivariate analysis is based in observation and analysis of more than one statistical outcome variable at a time. In design and analysis, the technique is used to perform trade studies across multiple dimensions while taking into account the effects of all variables on the responses of interest. The development of multivariate methods emerged to analyze large databases and increasingly complex data. Since the best way to represent the knowledge of reality is the modeling, we should use multivariate statistical methods. Multivariate methods are designed to simultaneously analyze data sets, i.e., the analysis of different variables for each person or object studied. Keep in mind at all times that all variables must be treated accurately reflect the reality of the problem addressed. There are different types of multivariate analysis and each one should be employed according to the type of variables to analyze: dependent, interdependence and structural methods. In conclusion, multivariate methods are ideal for the analysis of large data sets and to find the cause and effect relationships between variables; there is a wide range of analysis types that we can use.

IREB2 and GALC are associated with pulmonary artery enlargement in chronic obstructive pulmonary disease

Pulmonary hypertension is associated with advanced chronic obstructive pulmonary disease (COPD), although pulmonary vascular changes occur early in the course of the disease. Pulmonary artery (PA) enlargement (PAE) measured by computed tomography correlates with pulmonary hypertension and COPD exacerbation frequency. Genome-wide association studies of PAE in subjects with COPD have not been reported. To investigate whether genetic variants are associated with PAE within subjects with COPD, we investigated data from current and former smokers from the COPDGene Study and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study. The ratio of the diameter of the PA to the diameter of the aorta (A) was measured using computed tomography. PAE was defined as PA/A greater than 1. A genome-wide association study for COPD with PAE was performed using subjects with COPD without PAE (PA/A ≤ 1) as a control group. A secondary analysis used smokers with normal spirometry as a control group. Genotyping was performed on Illumina platforms. The results were summarized using fixed-effect meta-analysis. Both meta-analyses revealed a genome-wide significant locus on chromosome 15q25.1 in IREB2 (COPD with versus without PAE, rs7181486; odds ratio [OR] = 1.32; P = 2.10 × 10(-8); versus smoking control subjects, rs2009746; OR = 1.42; P = 1.32 × 10(-9)). PAE was also associated with a region on 14q31.3 near the GALC gene (rs7140285; OR = 1.55; P = 3.75 × 10(-8)). Genetic variants near IREB2 and GALC likely contribute to genetic susceptibility to PAE associated with COPD. This study provides evidence for genetic heterogeneity associated with a clinically important COPD vascular subtype.

Blood eosinophil counts, exacerbations, and response to the addition of inhaled fluticasone furoate to vilanterol in patients with chronic obstructive pulmonary disease: a secondary analysis of data from two parallel randomised controlled trials

BACKGROUND

The short-term benefits of inhaled corticosteroids for patients with chronic obstructive pulmonary disease (COPD) are greater in patients with evidence of eosinophilic airway inflammation. We investigated whether blood eosinophil count is a useful biomarker of the long-term effect of the inhaled corticosteroid fluticasone furoate on exacerbation frequency.

METHODS

We did a post-hoc analysis of data from two replicate, randomised, double-blind trials of 12 months' duration (Sept 25, 2009 to Oct 21, 2011 and Oct 17, 2011) in which once a day vilanterol 25 μg was compared with 25 μg vilanterol plus 50 μg, 100 μg, or 200 μg fluticasone furoate in patients with moderate-to-severe COPD and a history of one or more exacerbation in the previous year. We compared exacerbation rates according to two baseline eosinophil cell count strata (<2% and ≥2%), and according to four baseline percentage groupings. We also assessed lung function and incidence of pneumonia per strata in treatment groups.

FINDINGS

We included 3177 patients in the analyses, with 2083 patients (66%) having an eosinophil count of 2% or higher at study entry. Across all doses of inhaled corticosteroids, fluticasone furoate and vilanterol reduced exacerbations by 29% compared with vilanterol alone (mean 0·91 vs 1·28 exacerbations per patient per year; p<0·0001) in patients with eosinophil counts of 2% or higher, and by 10% (0·79 vs 0·89; p=0·2827) in patients with eosinophil counts lower than 2%. Reductions in exacerbations with fluticasone furoate and vilanterol, compared with vilanterol alone, were 24% in patients with baseline eosinophil counts of ≥2-<4%, 32% for those with counts of 4-<6%, and 42% for those with eosinophil counts of ≥6%. In patients treated with vilanterol alone, exacerbation rates increased progressively with increasing eosinophil count percentage category. Improvement in trough forced expiratory volume in 1 s (FEV1) and the increased risk of pneumonia with fluticasone furoate and vilanterol compared with vilanterol alone were not associated with eosinophil count.

INTERPRETATION

Blood eosinophil count is a promising biomarker of response to inhaled corticosteroids in patients with COPD. Blood eosinophil count could potentially be used to stratify patients for different exacerbation rate reduction strategies.

FUNDING

GlaxoSmithKline (study ID 201595).

Independent evaluation of a simple clinical prediction rule to identify right ventricular dysfunction in patients with shortness of breath

BACKGROUND

Many patients have unexplained persistent dyspnea after negative computed tomographic pulmonary angiography (CTPA). We hypothesized that many of these patients have isolated right ventricular (RV) dysfunction from treatable causes. We previously derived a clinical decision rule (CDR) for predicting RV dysfunction consisting of persistent dyspnea and normal CTPA, finding that 53% of CDR-positive patients had isolated RV dysfunction. Our goal is to validate this previously derived CDR by measuring the prevalence of RV dysfunction and outcomes in dyspneic emergency department patients.

METHODS

A secondary analysis of a prospective observational multicenter study that enrolled patients presenting with suspected PE was performed. We included patients with persistent dyspnea, a nonsignificant CTPA, and formal echo performed. Right ventricular dysfunction was defined as RV hypokinesis and/or dilation with or without moderate to severe tricuspid regurgitation.

RESULTS

A total of 7940 patients were enrolled. Two thousand six hundred sixteen patients were analyzed after excluding patients without persistent dyspnea and those with a significant finding on CTPA. One hundred ninety eight patients had echocardiography performed as standard care. Of those, 19% (95% confidence interval [CI], 14%-25%) and 33% (95% CI, 25%-42%) exhibited RV dysfunction and isolated RV dysfunction, respectively. Patients with isolated RV dysfunction or overload were more likely than those without RV dysfunction to have a return visit to the emergency department within 45 days for the same complaint (39% vs 18%; 95% CI of the difference, 4%-38%).

CONCLUSION

This simple clinical prediction rule predicted a 33% prevalence of isolated RV dysfunction or overload. Patients with isolated RV dysfunction had higher recidivism rates and a trend toward worse outcomes.

Large trials, new knowledge: the changing face of COPD management

Large, well-designed, drug-treatment trials have allowed useful advances to be made in the treatment and diagnosis of chronic obstructive pulmonary disease (COPD). The two main clinical trial designs that provide evidence of effectiveness are randomised controlled trials (RCTs) and observational studies. RCTs are generally considered to provide more robust evidence than that obtained from observational studies and can generate informative secondary analyses in addition to the primary research query. In COPD, however, well-designed comparator-controlled RCTs, although successful, have been shown to have some limitations, such as a lack of generalisability. The findings of observational studies, whilst prone to bias, can generate valuable data and have also provided useful information relating to the efficacy of treatments in the current COPD management guidelines. This review focuses on major COPD studies published since 2007 (including UPLIFT, TIOSPIR, ECLIPSE and COPDGene), and assesses the influence such RCTs and large observational studies have had on our knowledge of COPD, and how these may impact future trial designs.

Heart failure and respiratory hospitalizations are reduced in patients with heart failure and chronic obstructive pulmonary disease with the use of an implantable pulmonary artery pressure monitoring device

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a frequent comorbidity in patients with heart failure (HF). Elevated pulmonary arterial (PA) pressure can be seen in both conditions and has been shown to predict morbidity and mortality.

METHODS AND RESULTS

A total of 550 subjects with New York Heart Association functional class III HF were randomly assigned to the treatment (n = 270) and control (n = 280) groups in the CHAMPION Trial. Physicians had access to the PA pressure measurements in the treatment group only, in which HF therapy was used to lower the elevated pressures. HF and respiratory hospitalizations were compared in both groups. A total of 187 subjects met criteria for classification into the COPD subgroup. In the entire cohort, the treatment group had a 37% reduction in HF hospitalization rates (P < .0001) and a 49% reduction in respiratory hospitalization rates (P = .0061). In the COPD subgroup, the treatment group had a 41% reduction in HF hospitalization rates (P = .0009) and a 62% reduction in respiratory hospitalization rates (P = .0023). The rate of respiratory hospitalizations in subjects without COPD was not statistically different (P = .76).

CONCLUSIONS

HF management incorporating hemodynamic information from an implantable PA pressure monitor significantly reduces HF and respiratory hospitalizations in HF subjects with comorbid COPD compared with standard care.

[COPD and heart disease]

Cardiovascular diseases are highly prevalent in patients with chronic obstructive pulmonary disease (COPD). Approximately one out of three patients with COPD dies of cardiovascular disease. Overlap syndrome (COPD and obstructive sleep apnea), pulmonary hypertension and lung hyperinflation have a further impact on cardiovascular function in patients with COPD.

Parametric response mapping monitors temporal changes on lung CT scans in the subpopulations and intermediate outcome measures in COPD Study (SPIROMICS)

RATIONALE AND OBJECTIVES

The longitudinal relationship between regional air trapping and emphysema remains unexplored. We have sought to demonstrate the utility of parametric response mapping (PRM), a computed tomography (CT)-based biomarker, for monitoring regional disease progression in chronic obstructive pulmonary disease (COPD) patients, linking expiratory- and inspiratory-based CT metrics over time.

MATERIALS AND METHODS

Inspiratory and expiratory lung CT scans were acquired from 89 COPD subjects with varying Global Initiative for Chronic Obstructive Lung Disease (GOLD) status at 30 days (n = 13) or 1 year (n = 76) from baseline as part of the Subpopulations and Intermediate Outcome Measures in COPD Study (SPIROMICS) clinical trial. PRMs of CT data were used to quantify the relative volumes of normal parenchyma (PRM(Normal)), emphysema (PRM(Emph)), and functional small airways disease (PRM(fSAD)). PRM measurement variability was assessed using the 30-day interval data. Changes in PRM metrics over a 1-year period were correlated to pulmonary function (forced expiratory volume at 1 second [FEV1]). A theoretical model that simulates PRM changes from COPD was compared to experimental findings.

RESULTS

PRM metrics varied by ∼6.5% of total lung volume for PRM(Normal) and PRM(fSAD) and 1% for PRM(Emph) when testing 30-day repeatability. Over a 1-year interval, only PRM(Emph) in severe COPD subjects produced significant change (19%-21%). However, 11 of 76 subjects showed changes in PRM(fSAD) greater than variations observed from analysis of 30-day data. Mathematical model simulations agreed with experimental PRM results, suggesting fSAD is a transitional phase from normal parenchyma to emphysema.

CONCLUSIONS

PRM of lung CT scans in COPD patients provides an opportunity to more precisely characterize underlying disease phenotypes, with the potential to monitor disease status and therapy response.

A score to predict short-term risk of COPD exacerbations (SCOPEX)

Background

There is no clinically useful score to predict chronic obstructive pulmonary disease (COPD) exacerbations. We aimed to derive this by analyzing data from three existing COPD clinical trials of budesonide/formoterol, formoterol, or placebo in patients with moderate-to-very-severe COPD and a history of exacerbations in the previous year.

Methods

Predictive variables were selected using Cox regression for time to first severe COPD exacerbation. We determined absolute risk estimates for an exacerbation by identifying variables in a binomial model, adjusting for observation time, study, and treatment. The model was further reduced to clinically useful variables and the final regression coefficients scaled to obtain risk scores of 0–100 to predict an exacerbation within 6 months. Receiver operating characteristic (ROC) curves and the corresponding C-index were used to investigate the discriminatory properties of predictive variables.

Results

The best predictors of an exacerbation in the next 6 months were more COPD maintenance medications prior to the trial, higher mean daily reliever use, more exacerbations during the previous year, lower forced expiratory volume in 1 second/forced vital capacity ratio, and female sex. Using these risk variables, we developed a score to predict short-term (6-month) risk of COPD exacerbations (SCOPEX). Budesonide/formoterol reduced future exacerbation risk more than formoterol or as-needed short-acting β₂-agonist (salbutamol).

Conclusion

SCOPEX incorporates easily identifiable patient characteristics and can be readily applied in clinical practice to target therapy to reduce COPD exacerbations in patients at the highest risk.

Prognostic value of serum growth differentiation factor-15 in patients with chronic obstructive pulmonary disease exacerbation

BACKGROUND

Information regarding prognostic value of growth differentiation factor 15 (GDF-15) and heart-type fatty acid-binding protein (H-FABP) in patients with chronic obstructive pulmonary disease (COPD) exacerbation is limited. The aim of this study was to investigate whether serum levels of GDF-15 and H-FABP predict an adverse outcome for COPD exacerbation.

METHODS

Clinical variables, including serum GDF-15 and H-FABP levels were compared in prospectively enrolled patients with COPD exacerbation that did or did not experience an adverse outcome. An adverse outcome included 30-day mortality and need for endotracheal intubation or inotropic support.

RESULTS

Ninety-seven patients were included and allocated into an adverse outcome (n=10) or a control (n=87) group. Frequencies of mental change and PaCO2>37 mm Hg were significantly higher in the adverse outcome group (mental change: 30% vs. 6%, p=0.034 and PaCO2>37 mm Hg: 80% vs. 22%, p<0.001, respectively). Serum GDF-15 elevation (>1,600 pg/mL) was more common in the adverse outcome group (80% vs. 43%, p=0.041). However, serum H-FABP level and frequency of serum H-FABP elevation (>755 pg/mL) did not differ between the two groups. Multivariate analysis showed that an elevated serum GDF-15 and PaCO2>37 mm Hg were significant predictors of an adverse outcome (odds ratio [OR], 25.8; 95% confidence interval [CI], 2.7-243.8; p=0.005 and OR, 11.8; 95% CI, 1.2-115.3; p=0.034, respectively).

CONCLUSION

Elevated serum GDF-15 level and PaCO2>37 mm Hg were found to predict an adverse outcome independently in patients with COPD exacerbation, suggesting the possibility that serum GDF-15 could be used as a prognostic biomarker of COPD exacerbation.

CT-base pulmonary artery measurement in the detection of pulmonary hypertension: a meta-analysis and systematic review

To summarize the performance of CT-based main pulmonary artery diameter or pulmonary artery to aorta ratio (PA:A ratio) measurement in detection of pulmonary hypertension by a systematic review and meta-analysis. A comprehensive literature search was performed to identify studies determining diagnostic accuracy of main pulmonary artery diameter or PA:A ratio measurement for pulmonary hypertension. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess the quality of the included studies. A bivariate random-effects model was used to pool sensitivity, specificity, positive/negative likelihood ratio (PLR/NLR), and diagnostic odds ratio (DOR). Summary receiver operating characteristic (SROC) curves and area under the curve (AUC) were used to summarize overall diagnostic performance. This meta-analysis included 20 publications involving 2134 subjects. Summary estimates for main pulmonary artery diameter measurement in the diagnosis of pulmonary hypertension were as follows: sensitivity, 0.79 (95% CI 0.72-0.84); specificity, 0.83 (95% CI 0.75-0.89); PLR, 4.68 (95% CI 3.13-6.99); NLR, 0.26 (95% CI 0.20-0.33); DOR, 18.13 (95% CI 10.87-30.24); and AUC 0.87. The corresponding summary performance estimates for using the PA:A ratio were as follows: sensitivity, 0.74 (95% CI 0.66-0.80); specificity, 0.81 (95% CI 0.74-0.86); PLR, 3.83 (95% CI, 2.70-5.43); NLR, 0.33 (95% CI 0.24-0.44); DOR, 11.77 (95% CI 6.60-21.00); and AUC 0.84. Both main pulmonary artery diameter and PA:A ratio are helpful for diagnosing pulmonary hypertension. Nevertheless, the results of pulmonary artery measurement should be interpreted in parallel with the results of traditional tests such as echocardiography.

Multi-scale analysis of imaging features and its use in the study of COPD exacerbation susceptible phenotypes

We propose a novel framework for exploring patterns of respiratory pathophysiology from paired breath-hold CT scans. This is designed to enable analysis of large datasets with the view of determining relationships between functional measures, disease state and the likelihood of disease progression. The framework is based on the local distribution of image features at various anatomical scales. Principal Component Analysis is used to visualise and quantify the multi-scale anatomical variation of features, whilst the distribution subspace can be exploited within a classification setting. This framework enables hypothesis testing related to the different phenotypes implicated in Chronic Obstructive Pulmonary Disease (COPD). We illustrate the potential of our method on initial results from a subset of patients from the COPDGene study, who are exacerbation susceptible and non-susceptible.

Cor pulmonale parvus in chronic obstructive pulmonary disease and emphysema: the MESA COPD study

BACKGROUND

The classic cardiovascular complication of chronic obstructive pulmonary disease (COPD) is cor pulmonale or right ventricular (RV) enlargement. Most studies of cor pulmonale were conducted decades ago.

OBJECTIVES

This study sought to examine RV changes in contemporary COPD and emphysema using cardiac magnetic resonance (CMR) imaging.

METHODS

We performed a case-control study nested predominantly in 2 general population studies of 310 participants with COPD and control subjects 50 to 79 years of age with ≥10 pack-years of smoking who were free of clinical cardiovascular disease. RV volumes and mass were assessed using magnetic resonance imaging. COPD and COPD severity were defined according to standard spirometric criteria. The percentage of emphysema was defined as the percentage of lung regions <-950 Hounsfield units on full-lung computed tomography; emphysema subtypes were scored by radiologists. Results were adjusted for age, race/ethnicity, sex, height, weight, smoking status, pack-years, systemic hypertension, and sleep apnea.

RESULTS

Right ventricular end-diastolic volume (RVEDV) was reduced in COPD compared with control subjects (-7.8 ml; 95% confidence interval: -15.0 to -0.5 ml; p = 0.04). Increasing severity of COPD was associated with lower RVEDV (p = 0.004) and lower RV stroke volume (p < 0.001). RV mass and ejection fraction were similar between the groups. A greater percentage of emphysema also was associated with lower RVEDV (p = 0.005) and stroke volume (p < 0.001), as was the presence of centrilobular and paraseptal emphysema.

CONCLUSIONS

RV volumes are lower without significant alterations in RV mass and ejection fraction in contemporary COPD, and this reduction is related to the greater percentage of emphysema on computed tomography.

Predictors of chronic obstructive pulmonary disease exacerbations

PURPOSE OF REVIEW

A frequent-exacerbation phenotype of chronic obstructive pulmonary disease (COPD) exists that is independent of disease severity. Establishment of methods to predict 'frequent exacerbators' is critical. The purpose of this review is to critically assess the recent literature regarding predicting COPD exacerbations, and to provide recommendations for future research.

RECENT FINDINGS

Although there are many studies in which inflammatory biomarkers have been used in an attempt to predict future exacerbations, it is likely that these biomarkers represent a consequence rather than the cause. Genetic predictors are involved in causal pathways. Thus, genetics should be investigated in order to understand the exacerbation mechanism and to develop new therapeutic approaches. Some single nucleotide-type genetic polymorphisms are associated with exacerbations, and the individuals with genotypes protective against infection are less susceptible to exacerbations. In contrast, we reported that loss of Siglec-14, a lectin likely involved in host defense, was associated with a reduced COPD exacerbation risk.

SUMMARY

We should take into consideration that a protein involved in host defense such as Siglec-14, that could also trigger exaggerated response, might also generate unwanted local and systemic inflammation, which could be detrimental to a host and could generate COPD with a frequent-exacerbation phenotype, its progression, and its comorbidities.

A combined pulmonary function and emphysema score prognostic index for staging in Chronic Obstructive Pulmonary Disease

Introduction

Chronic Obstructive Pulmonary Disease (COPD) is characterized by high morbidity and mortality. Lung computed tomography parameters, individually or as part of a composite index, may provide more prognostic information than pulmonary function tests alone.

Aim

To investigate the prognostic value of emphysema score and pulmonary artery measurements compared with lung function parameters in COPD and construct a prognostic index using a contingent staging approach.

Material-Methods

Predictors of mortality were assessed in COPD outpatients whose lung computed tomography, spirometry, lung volumes and gas transfer data were collected prospectively in a clinical database. Univariate and multivariate Cox proportional hazard analysis models with bootstrap techniques were used.

Results

169 patients were included (59.8% male, 61.1 years old; Forced Expiratory Volume in 1 second % predicted: 40.5±19.2). 20.1% died; mean survival was 115.4 months. Age (HR = 1.098, 95% Cl = 1.04–1.252) and emphysema score (HR = 1.034, 95% CI = 1.007–1.07) were the only independent predictors of mortality. Pulmonary artery dimensions were not associated with survival. An emphysema score of 55% was chosen as the optimal threshold and 30% and 65% as suboptimals. Where emphysema score was between 30% and 65% (intermediate risk) the optimal lung volume threshold, a functional residual capacity of 210% predicted, was applied. This contingent staging approach separated patients with an intermediate risk based on emphysema score alone into high risk (Functional Residual Capacity ≥210% predicted) or low risk (Functional Residual Capacity <210% predicted). This approach was more discriminatory for survival (HR = 3.123; 95% CI = 1.094–10.412) than either individual component alone.

Conclusion

Although to an extent limited by the small sample size, this preliminary study indicates that the composite Emphysema score-Functional Residual Capacity index might provide a better separation of high and low risk patients with COPD, than other individual predictors alone.

Cardiopulmonary coupling in chronic obstructive pulmonary disease: the role of imaging

Chronic obstructive pulmonary disorder (COPD) is a systemic disease that affects the cardiovascular system through multiple pathways. Pulmonary hypertension, ventricular dysfunction, and atherosclerosis are associated with smoking and COPD, causing significant morbidity and poor prognosis. Coupling between the pulmonary and cardiovascular system involves mechanical interdependence and inflammatory pathways that potentially affect the entire circulation. Although treatments specific for COPD-related cardiovascular and pulmonary vascular disease are limited, early diagnosis, study of pathophysiology, and monitoring the effects of treatment are enhanced with improved imaging techniques. In this article, we review recent advancements in the imaging of the vasculature and the heart in patients with COPD. We also explore the potential mechanism of coupling between the progression of COPD and vascular disease. Imaging methods reviewed include specific implementations of computed tomography, magnetic resonance imaging, dual-energy computed tomography, positron emission tomography, and echocardiography. Specific applications to the proximal and distal pulmonary vasculature, as well as to the heart and systemic circulation, are also discussed.

Low-normal lung volume correlates with pulmonary hypertension in fibrotic idiopathic interstitial pneumonia: computer-aided 3D quantitative analysis of chest CT

OBJECTIVE

We investigated whether the lung volume determined on CT, especially the volume of the normal lung, is correlated with mean pulmonary artery pressure (PAP) in patients with chronic fibrosing idiopathic interstitial pneumonia (IIP).

MATERIALS AND METHODS

The subjects were 40 patients with IIP who underwent right heart catheterization (RHC) and chest CT. Thirty-three patients (82.5%) were smokers or former smokers. Using a computer-aided system, the lungs in the 3D CT images were automatically categorized pixel-by-pixel with gaussian histogramnormalized correlations, and the relative volume of each lesion to the CT lung volume was calculated as "normal(%)," "ground-glass opacities(%)," "consolidation(%)," "emphysema(%)," and "fibrosis(%)." The relationship between each "volume(%)" and pulmonary hypertension was evaluated using logistic regression analysis. ROC curves were constructed to assess the predictive value of these CT-based volumes in the identification of pulmonary hypertension.

RESULTS

Sixteen patients had pulmonary hypertension at rest (mean PAP > 25 mm Hg on RHC). Emphysema constituted more than 10% of the CT lung volume in 13 patients. On multivariate analysis of each volume(%), normal(%) was significant for detecting pulmonary hypertension (odds ratio, 0.92; 95% CI, 0.86-0.96; p = 0.02). On ROC analysis, the AUC of normal(%) was 0.849 (0.731-0.967).

CONCLUSION

The relative CT volume of any single lesion was of limited value in predicting pulmonary hypertension in patients with pulmonary fibrosis and emphysema. In these patients, normal(%), measured by a 3D computer-aided system, was correlated with pulmonary hypertension measured by RHC.

Predictors of exacerbations in chronic obstructive pulmonary disease--results from the Bergen COPD cohort study

Background

COPD exacerbations accelerate disease progression.

Aims

To examine if COPD characteristics and systemic inflammatory markers predict the risk for acute COPD exacerbation (AECOPD) frequency and duration.

Methods

403 COPD patients, GOLD stage II-IV, aged 44–76 years were included in the Bergen COPD Cohort Study in 2006/07, and followed for 3 years. Examined baseline predictors were sex, age, body composition, smoking, AECOPD the last year, GOLD stage, Charlson comorbidity score (CCS), hypoxemia (PaO2<8 kPa), cough, use of inhaled steroids, and the inflammatory markers leucocytes, C-reactive protein (CRP), neutrophil gelatinase associated lipocalin (NGAL), soluble tumor necrosis factor receptor 1 (sTNF-R1), and osteoprotegrin (OPG). Negative binomial models with random effects were fitted to estimate the annual incidence rate ratios (IRR). For analysis of AECOPD duration, a generalized estimation equation logistic regression model was fitted, also adjusting for season, time since inclusion and AECOPD severity.

Results

After multivariate adjustment, significant predictors of AECOPD were: female sex [IRR 1.45 (1.14–1.84)], age per 10 year increase [1.23 (1.03–1.47)], >1 AECOPD last year before baseline [1.65 (1.24–2.21)], GOLD III [1.36 (1.07–1.74)], GOLD IV [2.90 (1.98–4.25)], chronic cough [1.64 (1.30–2.06)] and use of inhaled steroids [1.57 (1.21–2.05)]. For AECOPD duration more than three weeks, significant predictors after adjustment were: hypoxemia [0.60 (0.39–0.92)], years since inclusion [1.19 (1.03–1.37)], AECOPD severity; moderate [OR 1.58 (1.14–2.18)] and severe [2.34 (1.58–3.49)], season; winter [1.51 (1.08–2.12)], spring [1.45 (1.02–2.05)] and sTNF-R1 per SD increase [1.16 (1.00–1.35)].

Conclusion

Several COPD characteristics were independent predictors of both AECOPD frequency and duration.

Prediction of acute respiratory disease in current and former smokers with and without COPD

BACKGROUND

The risk factors for acute episodes of respiratory disease in current and former smokers who do not have COPD are unknown.

METHODS

Eight thousand two hundred forty-six non-Hispanic white and black current and former smokers in the Genetic Epidemiology of COPD (COPDGene) cohort had longitudinal follow-up (LFU) every 6 months to determine acute respiratory episodes requiring antibiotics or systemic corticosteroids, an ED visit, or hospitalization. Negative binomial regression was used to determine the factors associated with acute respiratory episodes. A Cox proportional hazards model was used to determine adjusted hazard ratios (HRs) for time to first episode and an acute episode of respiratory disease risk score.

RESULTS

At enrollment, 4,442 subjects did not have COPD, 658 had mild COPD, and 3,146 had moderate or worse COPD. Nine thousand three hundred three acute episodes of respiratory disease and 2,707 hospitalizations were reported in LFU (3,044 acute episodes of respiratory disease and 827 hospitalizations in those without COPD). Major predictors included acute episodes of respiratory disease in year prior to enrollment (HR, 1.20; 95% CI, 1.15-1.24 per exacerbation), airflow obstruction (HR, 0.94; 95% CI, 0.91-0.96 per 10% change in % predicted FEV1), and poor health-related quality of life (HR, 1.07; 95% CI, 1.06-1.08 for each 4-unit increase in St. George's Respiratory Questionnaire score). Risks were similar for those with and without COPD.

CONCLUSIONS

Although acute episode of respiratory disease rates are higher in subjects with COPD, risk factors are similar, and at a population level, there are more episodes in smokers without COPD.

Clinical relevance of bronchial anthracofibrosis in patients with chronic obstructive pulmonary disease exacerbation

Background

Bronchial anthracofibrosis (BAF), which is associated with exposure to biomass smoke in inefficiently ventilated indoor areas, can take the form of obstructive lung disease. Patients with BAF can mimic or present with an exacerbation of chronic obstructive pulmonary disease (COPD). The purpose of the current study was to investigate the prevalence of BAF in Korean patients with COPD exacerbation as well as to examine the clinical features of these patients in order to determine its clinical relevance.

Methods

A total of 206 patients with COPD exacerbation were divided into BAF and non-BAF groups, according to computed tomography findings. We compared both clinical and radiologic variables between the two groups.

Results

Patients with BAF (51 [25%]) were older, with a preponderance of nonsmoking women; moreover, they showed a more frequent association with exposure to wood smoke compared to those without BAF. However, no differences in the severity of illness and clinical course between the two groups were observed. Patients in the BAF group had less severe airflow obstruction, but more common and severe pulmonary hypertension signs than those in the non-BAF group.

Conclusion

Compared with non-BAF COPD, BAF may be associated with milder airflow limitation and more frequent signs of pulmonary hypertension with a more severe grade in patients presenting with COPD exacerbation.

Enlarged pulmonary artery is predicted by vascular injury biomarkers and is associated with WTC-Lung Injury in exposed fire fighters: a case-control study

OBJECTIVES

We hypothesise that there is an association between an elevated pulmonary artery/aorta (PA/A) and World Trade Center-Lung Injury (WTC-LI). We assessed if serum vascular disease biomarkers were predictive of an elevated PA/A.

DESIGN

Retrospective case-cohort analysis of thoracic CT scans of WTC-exposed firefighters who were symptomatic between 9/12/2001 and 3/10/2008. Quantification of vascular-associated biomarkers from serum collected within 200 days of exposure.

SETTING

Urban tertiary care centre and occupational healthcare centre.

PARTICIPANTS

Male never-smoking firefighters with accurate pre-9/11 forced expiratory volume in 1 s (FEV1)≥75%, serum sampled ≤200 days of exposure was the baseline cohort (n=801). A subcohort (n=97) with available CT scans and serum biomarkers was identified. WTC-LI was defined as FEV1≤77% at the subspecialty pulmonary evaluation (n=34) and compared with controls (n=63) to determine the associated PA/A ratio. The subcohort was restratified based on PA/A≥0.92 (n=38) and PA/A<0.92(n=59) to determine serum vascular biomarkers that were predictive of this vasculopathy.

OUTCOME MEASURES

The primary outcome of this study was to identify a PA/A ratio in a cohort of individuals exposed to WTC dust that was associated with WTC-LI. The secondary outcome was to identify serum biomarkers predictive of the PA/A ratio using logistic regression.

RESULTS

PA/A≥0.92 was associated with WTC-LI, OR of 4.02 (95% CI 1.21 to 13.41; p=0.023) when adjusted for exposure, body mass index and age at CT. Elevated macrophage derived chemokine and soluble endothelial selectin were predictive of PA/A≥0.92, (OR, 95% CI 2.08, 1.05 to 4.11, p=0.036; 1.33, 1.06 to 1.68, p=0.016, respectively), while the increased total plasminogen activator inhibitor 1 was predictive of not having PA/A≥0.92 (OR 0.88, 0.79 to 0.98; p=0.024).

CONCLUSIONS

Elevated PA/A was associated with WTC-LI. Development of an elevated PA/A was predicted by biomarkers of vascular disease found in serum drawn within 6 months of WTC exposure. Increased PA/A is a potentially useful non-invasive biomarker of WTC-LI and warrants further study.

Prevention of Exacerbations in Chronic Obstructive Pulmonary Disease: Knowns and Unknowns

The 2011 recommendations of the Global initiative for chronic Obstructive Lung Disease (GOLD) constituted a major paradigm shift in COPD management since they set 2 major goals for the assessment and management of patients: (1) the reduction of their current level of symptoms (i.e., treat the patient today); and (2) the reduction of their risk of exacerbations (i.e., prevent them tomorrow). Exacerbations are not only an important clinical endpoint in patients with COPD, but they are also a risk factor themselves for additional adverse outcomes since they have been shown to increase the risk for mortality, to accelerate the decline in pulmonary function, and to decrease health status and quality of life. Despite their importance, many unanswered questions related to exacerbations remain. The purpose of this review is to discuss: (1)knowns and unknowns in our current understanding of exacerbations, (2) what known factors increase their risk, and (3) how to best prevent them.

Pulmonary artery size as a predictor of pulmonary hypertension and outcomes in patients with chronic obstructive pulmonary disease

RATIONALE

The relationship between pulmonary artery size with underlying pulmonary hypertension and mortality remains to be determined in COPD. We sought to evaluate the relationships in a cohort of patients with advanced COPD.

METHODS

A retrospective study of advanced COPD patients evaluated between 1998 and 2012 was conducted at a tertiary care center. Patients with chest computed tomography images and right heart catheterizations formed the study cohort. The diameters of the pulmonary artery and ascending aorta were measured by independent observers and compared to pulmonary artery pressures. Intermediate-term mortality was evaluated for the 24-month period subsequent to the respective studies. Cox proportional hazards model was used to determine independent effects of variables on survival.

RESULTS

There were 65 subjects identified, of whom 38 (58%) had pulmonary hypertension. Patients with and without pulmonary hypertension had mean pulmonary artery diameters of 34.4 mm and 29.1 mm, respectively (p = 0.0003). The mean PA:A ratio for those with and without pulmonary hypertension was 1.05 and 0.87, respectively (p = 0.0003). The PA:A ratio was an independent predictor of mortality with a reduced survival in those with a PA:A >1 (p = 0.008).

CONCLUSIONS

The PA:A ratio is associated with underlying pulmonary hypertension in patients with COPD and is an independent predictor of mortality. This readily available measurement may be a valuable non-invasive screening tool for underlying pulmonary hypertension in COPD patients and appears to impart important independent prognostic information.

[Pulmonary hypertension in chronic respiratory diseases]

Pulmonary hypertension is frequent in advanced chronic respiratory diseases, with an estimated prevalence at the time of pulmonary transplantation of 30-50 % in idiopathic pulmonary fibrosis, 30-50 % in chronic obstructive pulmonary disease, 50 % in combined pulmonary fibrosis and emphysema, 75 % in sarcoidosis, and more than 75 % of cases in pulmonary Langerhans cell histiocytosis. Histologic features include varying degrees of pulmonary arterial remodeling (prominent), vascular rarefaction (emphysema), fibrosis or specific involvement of the pulmonary arteries (idiopathic pulmonary fibrosis, sarcoidosis, lymphangioleiomyomatosis, pulmonary Langerhans cell histiocytosis), in situ thrombosis, and frequently associated involvement of the pulmonary veins (idiopathic pulmonary fibrosis, sarcoidosis). Pulmonary hypertension is usually detected using echocardiography with Doppler, however right heart catheterisation is required to confirm precapillary pulmonary hypertension defined by pulmonary artery pressure ≥ 25 mm Hg, with pulmonary artery wedge pressure ≤ 15 mm Hg. When present, it is associated with decreased exercise capacity and worse mortality. Pulmonary hypertension in chronic respiratory disease is almost invariably multifactorial; hypoxia is one of its main determinants, however supplemental oxygen therapy rarely reverses pulmonary hypertension. Management of pulmonary hypertension in chronic respiratory disease is mostly based on the optimal treatment of the underlying disease. Available data do not support the use of drug therapies specific for pulmonary hypertension in the setting of chronic respiratory diseases, however very few clinical studies have been conducted so far specifically in this context.

Phenotypic and genetic heterogeneity among subjects with mild airflow obstruction in COPDGene

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by marked phenotypic heterogeneity. Most previous studies have focused on COPD subjects with FEV1 < 80% predicted. We investigated the clinical and genetic heterogeneity in subjects with mild airflow limitation in spirometry grade 1 defined by the Global Initiative for chronic Obstructive Lung Disease (GOLD 1).

METHODS

Data from current and former smokers participating in the COPDGene Study (NCT00608764) were analyzed. K-means clustering was performed to explore subtypes within 794 GOLD 1 subjects. For all subjects with GOLD 1 and with each cluster, a genome-wide association study and candidate gene testing were performed using smokers with normal lung function as a control group. Combinations of COPD genome-wide significant single nucleotide polymorphisms (SNPs) were tested for association with FEV1 (% predicted) in GOLD 1 and in a combined group of GOLD 1 and smoking control subjects.

RESULTS

K-means clustering of GOLD 1 subjects identified putative "near-normal", "airway-predominant", "emphysema-predominant" and "lowest FEV1% predicted" subtypes. In non-Hispanic whites, the only SNP nominally associated with GOLD 1 status relative to smoking controls was rs7671167 (FAM13A) in logistic regression models with adjustment for age, sex, pack-years of smoking, and genetic ancestry. The emphysema-predominant GOLD 1 cluster was nominally associated with rs7671167 (FAM13A) and rs161976 (BICD1). The lowest FEV1% predicted cluster was nominally associated with rs1980057 (HHIP) and rs1051730 (CHRNA3). Combinations of COPD genome-wide significant SNPs were associated with FEV1 (% predicted) in a combined group of GOLD 1 and smoking control subjects.

CONCLUSIONS

Our results indicate that GOLD 1 subjects show substantial clinical heterogeneity, which is at least partially related to genetic heterogeneity.

Pulmonary hypertension and right heart dysfunction in chronic lung disease

Group 3 pulmonary hypertension (PH) is a common complication of chronic lung disease (CLD), including chronic obstructive pulmonary disease (COPD), interstitial lung disease, and sleep-disordered breathing. Development of PH is associated with poor prognosis and may progress to right heart failure, however, in the majority of the patients with CLD, PH is mild to moderate and only a small number of patients develop severe PH. The pathophysiology of PH in CLD is multifactorial and includes hypoxic pulmonary vasoconstriction, pulmonary vascular remodeling, small vessel destruction, and fibrosis. The effects of PH on the right ventricle (RV) range between early RV remodeling, hypertrophy, dilatation, and eventual failure with associated increased mortality. The golden standard for diagnosis of PH is right heart catheterization, however, evidence of PH can be appreciated on clinical examination, serology, radiological imaging, and Doppler echocardiography. Treatment of PH in CLD focuses on management of the underlying lung disorder and hypoxia. There is, however, limited evidence to suggest that PH-specific vasodilators such as phosphodiesterase-type 5 inhibitors, endothelin receptor antagonists, and prostanoids may have a role in the treatment of patients with CLD and moderate-to-severe PH.

Study design and rationale for investigating phosphodiesterase type 5 inhibition for the treatment of pulmonary hypertension due to chronic obstructive lung disease: the TADA-PHiLD (TADAlafil for Pulmonary Hypertension associated with chronic obstructive Lung Disease) trial

In patients with chronic obstructive pulmonary disease (COPD), moderate or severe pulmonary hypertension (COPD-PH) is associated with increased rates of morbidity and mortality. Despite this, approaches to treatment and the efficacy of phosphodiesterase type 5 inhibition (PDE-5i) in COPD-PH are unresolved. We present the clinical rationale and study design to assess the effect of oral tadalafil on exercise capacity, cardiopulmonary hemodynamics, and clinical outcome measures in COPD-PH patients. Male and female patients 40-85 years old with GOLD stage 2 COPD or higher and pulmonary hypertension diagnosed on the basis of invasive cardiac hemodynamic assessment (mean pulmonary artery pressure [mPAP] >30 mmHg, pulmonary vascular resistance [PVR] >2.5 Wood units, and pulmonary capillary wedge pressure ≤18 mmHg at rest) will be randomized at a 1∶1 ratio to receive placebo or oral PDE-5i with tadalafil (40 mg daily for 12 months). The primary end point is change from baseline in 6-minute walk distance at 12 months. The secondary end points are change from baseline in PVR and mPAP at 6 months and change from baseline in peak volume of oxygen consumption ([Formula: see text]) during exercise at 12 months. Changes in systemic blood pressure and/or oxyhemoglobin saturation (Sao2) at rest and during exercise will function as safety outcome measures. TADA-PHiLD (TADAlafil for Pulmonary Hypertension assocIated with chronic obstructive Lung Disease) is the first sufficiently powered randomized clinical trial testing the effect of PDE-5i on key clinical and drug safety outcome measures in patients with at least moderate PH due to COPD.

CT scan-measured pulmonary artery to aorta ratio and echocardiography for detecting pulmonary hypertension in severe COPD

BACKGROUND

COPD is associated with significant morbidity primarily driven by acute exacerbations. Relative pulmonary artery (PA) enlargement, defined as a PA to ascending aorta (A) diameter ratio greater than one (PA:A>1) identifies patients at increased risk for exacerbations. However, little is known about the correlation between PA:A, echocardiography, and invasive hemodynamics in COPD.

METHODS

A retrospective observational study of patients with severe COPD being evaluated for lung transplantation at a single center between 2007 and 2011 was conducted. Clinical characteristics, CT scans, echocardiograms, and right-sided heart catheterizations were reviewed. The PA diameter at the bifurcation and A diameter from the same CT image were measured. Linear and logistic regression were used to examine the relationships between PA:A ratio by CT scan and PA systolic pressure (PASP) by echocardiogram with invasive hemodynamics. Receiver operating characteristic analysis assessed the usefulness of the PA:A ratio and PASP in predicting resting pulmonary hypertension (PH) (mean pulmonary artery pressure [mPAP]>25 mm Hg).

RESULTS

Sixty patients with a mean predicted FEV1 of 27%±12% were evaluated. CT scan-measured PA:A correlated linearly with mPAP after adjustment for multiple covariates (r=0.30, P=.03), a finding not observed with PASP. In a multivariate logistic model, mPAP was independently associated with PA:A>1 (OR, 1.44; 95% CI, 1.02-2.04; P=.04). PA:A>1 was 73% sensitive and 84% specific for identifying patients with resting PH (area under the curve, 0.83; 95% CI, 0.72-0.93; P<.001), whereas PASP was not useful.

CONCLUSIONS

A PA:A ratio>1 on CT scan outperforms echocardiography for diagnosing resting PH in patients with severe COPD.

Progress in Imaging COPD, 2004 - 2014

Computed tomography (CT) has contributed substantially to our understanding of COPD over the past decade. Visual and quantitative assessments of CT in COPD are complementary. Visual assessment should provide assessment of centrilobular, panlobular and paraseptal emphysema, airway wall thickening, bronchiectasis, findings of respiratory bronchiolitis, and enlargement of the pulmonary artery. Quantitative CT permits evaluation of severity of emphysema, airway wall thickening, and expiratory air trapping, and is now being used for longitudinal evaluation of the progression of COPD. Innovative techniques are being developed to use CT to characterize the pattern of emphysema and smoking- related respiratory bronchiolitis. Magnetic resonance imaging (MRI) and positron emission tomography PET-CT are useful research tools in the evaluation of COPD.

A Decade of National Heart, Lung, and Blood Institute Programs Supporting COPD Research and Education

The past decade of research in chronic obstructive pulmonary disease (COPD) has seen a new age of understanding both pathogenic mechanisms and clinical manifestations of the disease. The National Heart, Lung, and Blood Institute (NHLBI) has helped guide this progress with a series of initiatives to stimulate COPD research in various ways. These initiatives were designed to promote a precision medicine approach to treating COPD, one that takes advantage of targeting particular molecular pathways and the individual pathobiologies of the diversity of COPD patients. This review describes the strategic objectives of these initiatives, as well as some of their observed and anticipated outcomes. In addition, we address parallel steps NHLBI has taken to promote COPD awareness among the public. As we look toward the immediate future of COPD research and education, we see a time of great progress in terms of understanding and treatment. Furthermore, while this remains a debilitating and disturbingly prevalent disease, as NHLBI looks even farther ahead, we envision emerging efforts toward COPD prevention.

COPD updates: what's new in pathophysiology and management?

The historic perspective that used to define chronic obstructive pulmonary disease has changed. As reviewed in this article, it is based on a better understanding of the underlying inflammatory airflow obstruction and a multidimensional classification, which mostly targets a subgroup called 'frequent exacerbators'. Clinical and radioimaging predictors are the stamina for an aggressive therapeutic approach. A simplified explanation of the updated Global Initiative for Obstructive Lung Disease guidelines will ease the burden of treatment selection.

Chronic obstructive pulmonary disease: respiratory review of 2013

Chronic obstructive pulmonary disease (COPD) is a common airway disease that has considerable impact on disease burdens and mortality rates. A large number of articles on COPD are published within the last few years. Many aspects on COPD ranging from risk factors to management have continued to be fertile fields of investigation. This review summarizes 6 clinical articles with regards to the risk factors, phenotype, assessment, exacerbation, management and prognosis of patients with COPD which were being published last year in major medical journals.

Pulmonary hypertension in chronic lung diseases

Chronic obstructive lung disease (COPD) and diffuse parenchymal lung diseases (DPLD), including idiopathic pulmonary fibrosis (IPF) and sarcoidosis, are associated with a high incidence of pulmonary hypertension (PH), which is linked with exercise limitation and a worse prognosis. Patients with combined pulmonary fibrosis and emphysema (CPFE) are particularly prone to the development of PH. Echocardiography and right heart catheterization are the principal modalities for the diagnosis of COPD and DPLD. For discrimination between group 1 PH patients with concomitant respiratory abnormalities and group 3 PH patients (PH caused by lung disease), patients should be transferred to a center with expertise in both PH and lung diseases for comprehensive evaluation. The task force encompassing the authors of this article provided criteria for this discrimination and suggested using the following definitions for group 3 patients, as exemplified for COPD, IPF, and CPFE: COPD/IPF/CPFE without PH (mean pulmonary artery pressure [mPAP] <25 mm Hg); COPD/IPF/CPFE with PH (mPAP ≥25 mm Hg); PH-COPD, PH-IPF, and PH-CPFE); COPD/IPF/CPFE with severe PH (mPAP ≥35 mm Hg or mPAP ≥25 mm Hg with low cardiac index [CI <2.0 l/min/m(2)]; severe PH-COPD, severe PH-IPF, and severe PH-CPFE). The "severe PH group" includes only a minority of chronic lung disease patients who are suspected of having strong general vascular abnormalities (remodeling) accompanying the parenchymal disease and with evidence of an exhausted circulatory reserve rather than an exhausted ventilatory reserve underlying the limitation of exercise capacity. Exertional dyspnea disproportionate to pulmonary function tests, low carbon monoxide diffusion capacity, and rapid decline of arterial oxygenation upon exercise are typical clinical features of this subgroup with poor prognosis. Studies evaluating the effect of pulmonary arterial hypertension drugs currently not approved for group 3 PH patients should focus on this severe PH group, and for the time being, these patients should be transferred to expert centers for individualized patient care.

Would screening for lung cancer benefit 75- to 84-year-old residents of the United States?

Background: The National Lung Screening Trial demonstrated that screening for lung cancer improved overall survival (OS) and reduced lung cancer mortality in the 55- to 74-year-old age group by increasing the proportion of cancers detected at an early stage. Because of the increasing life expectancy of the American population, we investigated whether screening for lung cancer might benefit men and women aged 75–84 years.

Materials/Methods: Rates of non-small cell lung cancer (NSCLC) from 2000 to 2009 were calculated in both younger and older age groups using the surveillance epidemiology and end reporting database. OS and lung cancer-specific survival (LCSS) in patients with Stage I NSCLC diagnosed from 2004 to 2009 were analyzed to determine the effects of age and treatment.

Results: The per capita incidence of NSCLC decreased in the 55–74 cohort, but increased in the 75–84 cohort over the study period. Crude lung cancer death rates in the two age groups who had no specific treatment were 39.5 and 44.9%, respectively. These rates fell in both age groups when increasingly aggressive treatment was used. Rates of OS and LCSS improved significantly with increasingly aggressive treatment in the 75–84 age group. The survival benefits of increasingly aggressive treatment in 75- to 84-year-old females did not differ from their counterparts in the younger cohort.

Conclusion: Screening for lung cancer might be of benefit to individuals at increased risk of lung cancer in the 75–84 age group. The survival benefits of aggressive therapy are similar in females between 55–74 and 75–84 years old.

Pulmonary arterial enlargement in patients with acute exacerbation of interstitial pneumonia

The purpose of this study was to evaluate change in the size of the main pulmonary (PA) artery in patients with acute exacerbation of interstitial pneumonia (IP). Twenty-nine patients underwent computed tomography at baseline and at the time of acute IP exacerbation for the measurement of the diameters of the main PA and the ascending aorta. We found that the diameter of the main PA was significantly larger at the time of acute IP exacerbation than at baseline, which might reflect the alterations in pulmonary circulation.

Causes and patterns of readmissions in patients with common comorbidities: retrospective cohort study

OBJECTIVE

To evaluate the primary diagnoses and patterns of 30 day readmissions and potentially avoidable readmissions in medical patients with each of the most common comorbidities.

DESIGN

Retrospective cohort study.

SETTING

Academic tertiary medical centre in Boston, 2009-10.

PARTICIPANTS

10,731 consecutive adult discharges from a medical department.

MAIN OUTCOME MEASURES

Primary readmission diagnoses of readmissions within 30 days of discharge and potentially avoidable 30 day readmissions to the index hospital or two other hospitals in its network.

RESULTS

Among 10,731 discharges, 2398 (22.3%) were followed by a 30 day readmission, of which 858 (8.0%) were identified as potentially avoidable. Overall, infection, neoplasm, heart failure, gastrointestinal disorder, and liver disorder were the most frequent primary diagnoses of potentially avoidable readmissions. Almost all of the top five diagnoses of potentially avoidable readmissions for each comorbidity were possible direct or indirect complications of that comorbidity. In patients with a comorbidity of heart failure, diabetes, ischemic heart disease, atrial fibrillation, or chronic kidney disease, the most common diagnosis of potentially avoidable readmission was acute heart failure. Patients with neoplasm, heart failure, and chronic kidney disease had a higher risk of potentially avoidable readmissions than did those without those comorbidities.

CONCLUSIONS

The five most common primary diagnoses of potentially avoidable readmissions were usually possible complications of an underlying comorbidity. Post-discharge care should focus attention not just on the primary index admission diagnosis but also on the comorbidities patients have.

Magnetic resonance and computed tomography imaging of the structural and functional changes of pulmonary arterial hypertension

The current Dana Point Classification system (2009) distinguishes elevation of pulmonary arterial pressure into pulmonary arterial hypertension (PAH) and pulmonary hypertension. Fortunately, PAH is not a common disease. However, with the aging of the First World's population, heart failure has become an important outcome of pulmonary hypertension, with up to 9% of the population involved. PAH is usually asymptomatic until late in the disease process. Although features that are indirectly related to PAH are found on noninvasive imaging studies, its diagnosis and management still require right heart catheterization. Imaging features of PAH include the following: (1) enlargement of the pulmonary trunk and main pulmonary arteries; (2) decreased pulmonary arterial compliance; (3) tapering of the peripheral pulmonary arteries; (4) enlargement of the inferior vena cava; and (5) increased mean transit time. The chronic requirement to generate high pulmonary arterial pressure measurably affects the right heart and main pulmonary artery. This change in physiology causes the following structural and functional alterations that have been shown to have prognostic significance: relative area change (RAC) of the pulmonary trunk, right ventricular stroke volume index, right ventricular stroke volume, right ventricular end-diastolic volume index, left ventricular end-diastolic volume index, and baseline right ventricular ejection fraction <35%. All of these variables can be quantified noninvasively and followed up longitudinally in each patient using magnetic resonance imaging to modify the treatment regimen. Untreated PAH frequently results in rapid clinical decline and death within 3 years of diagnosis. Unfortunately, even with treatment, fewer than half of these patients are alive at 4 years.

Pathophysiology and clinical implications of pulmonary arterial enlargement in COPD

Chronic obstructive pulmonary disease (COPD) is a complex condition defined by progressive airflow limitation in response to noxious stimuli, inflammation, and vascular changes. COPD exacerbations are critical events in the natural history of the disease, accounting for the majority of disease burden, cost, and mortality. Pulmonary vascular disease is an important risk factor for disease progression and exacerbation risk. Relative pulmonary artery enlargement on computed tomography scan, defined by a pulmonary artery to aortic (PA:A) ratio >1, has been evaluated as a marker of pulmonary vascular disease. The PA:A ratio can be measured reliably independent of electrocardiographic gating or the use of contrast, and in healthy patients a PA:A ratio >0.9 is considered to be abnormal. The PA:A ratio has been compared with invasive hemodynamic parameters, primarily mean pulmonary artery pressure in various disease conditions and is more strongly correlated with mean pulmonary artery pressure in obstructive as compared with interstitial lung disease. In patients without known cardiac or pulmonary disease, the PA:A ratio is predictive of mortality, while in COPD, an elevated PA:A ratio is correlated with increased exacerbation risk, outperforming other well established predictors of these events. Future studies should be aimed at determining the stability of the metric over time and evaluating the utility of the PA:A ratio in guiding specific therapies.