Sputum neutrophils as a biomarker in COPD: findings from the ECLIPSE study

<p>Abstract</p> <p>Introduction</p> <p>The percentage of neutrophils in sputum are increased in COPD patients, and may therefore be a biomarker of airway inflammation. We studied the relationships between sputum neutrophils and FEV₁, health status, exacerbation rates, systemic inflammation and emphysema, and long term variability at 1 year.</p> <p>Methods</p> <p>Sputum samples were obtained from 488 COPD patients within the ECLIPSE cohort. 359 samples were obtained at baseline, and 297 after 1 year. 168 subjects provided samples at both visits. Serum interleukin-6 (IL-6), IL-8, surfactant protein D and C-reactive protein levels were measured by immunoassays. Low-dose CT scans evaluated emphysema.</p> <p>Results</p> <p>Sputum neutrophil % increased with GOLD stage. There was a weak association between % sputum neutrophils and FEV₁% predicted (univariate r²= 0.025 and 0.094 at baseline and year 1 respectively, p < 0.05 after multivariate regression). Similar weak but significant associations were observed between neutrophil % and health status measured using the St Georges Respiratory Questionairre. There were no associations between neutrophils and exacerbation rates or emphysema. Associations between sputum neutrophils and systemic biomarkers were non-significant or similarly weak. The mean change over 1 year in neutrophil % was an increase of 3.5%.</p> <p>Conclusions</p> <p>Sputum neutrophil measurements in COPD are associated weakly with FEV₁% predicted and health status. Sputum neutrophil measurements were dissociated from exacerbation rates, emphysema and systemic inflammation.</p

Fibrinogen, chronic obstructive pulmonary disease (COPD) and outcomes in two United States cohorts

BACKGROUND: Fibrinogen is a marker of systemic inflammation and may be important in the pathogenesis and progression of chronic obstructive pulmonary disease (COPD). METHODS: We used baseline data from Atherosclerosis Risk in Communities and Cardiovascular Health Studies to determine the relation between fibrinogen levels and COPD and to examine how fibrinogen levels at baseline affected outcomes of death, development of COPD, lung function decline, and COPD-hospitalizations. RESULTS: Our study sample included 20,192 subjects, of whom 2995 died during the follow-up period. The mean fibrinogen level was 307.6 mg/dL and 10% of the sample had levels \u3e393.0 mg/dL. Subjects with Stage 3 or 4 COPD were more likely to have a fibrinogen level \u3e393.0 mg/dL (odds ratio 2.28, 95% confidence interval [CI]: 1.79-2.95). In the longitudinal adjusted models, fibrinogen levels \u3e393 mg/dL predicted mortality (hazards ratio 1.54, 95% CI: 1.39-1.70), COPD-related hospitalization (hazards ratio 1.45, 95% CI: 1.27-1.67), and incident Stage 2 COPD (odds ratio 1.36, 95% CI: 1.07-1.74). Similar findings were seen with continuous fibrinogen levels. CONCLUSION: In the Atherosclerosis Risk in Communities/Cardiovascular Health Studies cohort data, higher fibrinogen levels are predictors of mortality, COPD-related hospitalizations, and incident Stage 2 COPD

Altered Gene Expression in Blood and Sputum in COPD Frequent Exacerbators in the ECLIPSE Cohort

Patients with chronic obstructive pulmonary disease (COPD) who are defined as frequent exacerbators suffer with 2 or more exacerbations every year. The molecular mechanisms responsible for this phenotype are poorly understood. We investigated gene expression profile patterns associated with frequent exacerbations in sputum and blood cells in a well-characterised cohort. Samples from subjects from the ECLIPSE COPD cohort were used; sputum and blood samples from 138 subjects were used for microarray gene expression analysis, while blood samples from 438 subjects were used for polymerase chain reaction (PCR) testing. Using microarray, 150 genes were differentially expressed in blood (>±1.5 fold change, p≤0.01) between frequent compared to non-exacerbators. In sputum cells, only 6 genes were differentially expressed. The differentially regulated genes in blood included downregulation of those involved in lymphocyte signalling and upregulation of pro-apoptotic signalling genes. Multivariate analysis of the microarray data followed by confirmatory PCR analysis identified 3 genes that predicted frequent exacerbations; B3GNT, LAF4 and ARHGEF10. The sensitivity and specificity of these 3 genes to predict the frequent exacerbator phenotype was 88% and 33% respectively. There are alterations in systemic immune function associated with frequent exacerbations; down-regulation of lymphocyte function and a shift towards pro-apoptosis mechanisms are apparent in patients with frequent exacerbations

Aortic Pulse Wave Velocity as a Measure of Cardiovascular Risk in Chronic Obstructive Pulmonary Disease: Two-Year Follow-Up Data from the ARCADE Study

Background and objectives: Cardiovascular (CV) disease is a major cause of morbidity and mortality in chronic obstructive pulmonary disease (COPD). Patients with COPD have increased arterial stiffness, which may predict future CV risk. However, the development of arterial stiffness in COPD has not yet been studied prospectively. The Assessment of Risk in Chronic Airways Disease Evaluation (ARCADE) is a longitudinal study of CV risk and other comorbidities in COPD. The aims of this analysis were to explore factors associated with aortic pulse wave velocity (aPWV) at baseline and to describe the progression of aPWV in patients with COPD and comparators over two years. Materials and methods: At baseline, 520 patients with COPD (confirmed by spirometry) and 150 comparators free from respiratory disease were assessed for body composition, blood pressure, aPWV, noninvasive measures of cardiac output, inflammatory biomarkers, and exercise capacity. This was repeated after two years, and mortality cases and causes were also recorded. Results: At baseline, aPWV was greater in COPD patients 9.8 (95% confidence interval (CI) 9.7–10) versus comparators 8.7 (8.5–9.1) m/s (p < 0.01) after adjustments for age, mean arterial pressure (MAP), and heart rate. Mean blood pressure was 98 ± 11 in COPD patients and 95 ± 10 mmHg in comparators at baseline (p = 0.004). After two years, 301 patients and 105 comparators were fully reassessed. The mean (95% CI) aPWV increased similarly in patients 0.44 (0.25–0.63) and comparators 0.46 (0.23–0.69) m/s, without a change in blood pressure. At the two-year follow-up, there were 29 (6%) deaths in COPD patients, with the majority due to respiratory causes, with an overall dropout of 43% of patients with COPD and 30% of comparators. Conclusions: This was the first large longitudinal study of CV risk in COPD patients, and we confirmed greater aPWV in COPD patients than comparators after adjustments for confounding factors. After two years, patients and comparators had a similar increase of almost 0.5 m/s aPWV

Frailty: A global measure of the multisystem impact of COPD

Chronic obstructive pulmonary disease (COPD) is a multisystem disease that resembles the accumulation of multiple impairments seen in aging. A comprehensive geriatric assessment (CGA) captures multisystem deficits, from which a frailty index (FI) can be derived. We hypothesized that patients with COPD would be frailer than a comparator group free from respiratory disease. In this cross-sectional analysis, the CGA questionnaire was completed and used to derive an FI in 520 patients diagnosed with COPD and 150 comparators. All subjects were assessed for lung function, body composition, 6-minute walking distance (6MWD), and handgrip strength. Patients completed validated questionnaires on health-related quality of life and respiratory symptoms. Patients and comparators were similar in age, gender, and body mass index, but patients had a greater mean ± SD FI 0.16 ± 0.08 than comparators 0.05 ± 0.03. In patients, a stepwise linear regression 6MWD (β = −0.43), number of comorbidities (β = −0.38), handgrip (β = −0.11), and number of exacerbations (β = 0.11) were predictors of frailty (all p < 0.01). This large study suggests patients with COPD are frailer than comparators. The FI derived from the CGA captures the deterioration of multiple systems in COPD and provides an overview of impairments, which may identify individuals at increased risk of morbidity and mortality in COPD

Age-dependent elastin degradation is enhanced in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is primarily a lung condition characterised by the presence of persistent airflow limitation resulting from inflammation, remodelling of small airways, and emphysema. It is well-recognised that the impacts of COPD extend beyond the lung with many patients suffering systemic manifestations such as cardiovascular diseases that affect morbidity and mortality [1]. “Accelerated ageing” has been proposed as a mechanism that underlies many of the pulmonary and extrapulmonary consequences of COPD [2, 3]. It is thought that a decline in organ function is a feature of ageing in response to the accumulation of cell and molecular damage, and in the case of COPD, noxious inhalants such as tobacco smoke increase this damage, thus accelerating the ageing process, leading to the development of COPD. With the exception of lung function decline, however, evidence indicating that tobacco smoking or COPD accelerates age-associated deterioration remains scarce