Airflow Limitation and Endothelial Dysfunction. Unrelated and Independent Predictors of Atherosclerosis

Ultrasonic AccV: a potential indicator of peripheral arteriosclerosis in patients with chronic obstructive pulmonary disease

OBJECTIVE

This study aimed to investigate the risk factors for peripheral arteriosclerosis (PAS) and peripheral artery disease (PAD) in chronic obstructive pulmonary disease (COPD) patients and potential ultrasound indicators that could be used to improve detection.

METHOD

Outpatients seeking care between January 1, 2017, and December 31, 2020, in The First Affiliated Hospital of China Medical University were prospectively recruited. Subjects were divided into COPD and non-COPD (control) groups, and the COPD group was further divided into PAD and non-PAD subgroup, at the same time, PAS and non-PAS subgroup. Indicators of PAD -ankle-brachial index (ABI), indicators of PAS- pulse wave velocity (PWV), and ultrasound indices -peak systolic blood flow velocity (PSV) and blood flow acceleration velocity (AccV) were compared.

RESULT

Sixty-nine (61.6%) of 112 enrolled subjects had COPD. COPD patients had higher age, and blood pressure (BP)lower than controls. Seventeen (24.6%) COPD patients had PAD, the prevalence of PAD increases with the decrease of lung function, and seven (16.3%) non-COPD patients had PAD, however, there was no significant statistical difference between COPD and non-COPD groups. Fifty (72.5%) COPD patients had PAS, and thirty-four (79.1%) non-COPD patients had PAS, however, there was also no significant difference. The PAS subgroup had higher age, body mass index(BMI), body fat percentage(BFP), lower FEV1 and FEV1/FVC, as well as higher levels of right brachial artery and left dorsalis pedis artery AccV. Factors that correlated with ABI were 6MWD, post-bronchodilator FEV1, FEV1/ FVC, and maximal middle expiratory flow between 75% and 25% of FVC. Age, BP, and 6MWD, but not pulmonary function, were associated with brachial-ankle PWV (baPWV). There was a positive correlation between baPWV and radial artery AccV bilaterally.

CONCLUSION

Radial artery AccV correlated well with baPWV, which suggests that ultrasound could be used to assess both morphological and functional changes in vessels, may serving as a better method to identify PAS in high-risk COPD patients.

Pulmonary function and atherosclerosis in the general population: causal associations and clinical implications

Reduced lung function is associated with cardiovascular mortality, but the relationships with atherosclerosis are unclear. The population-based Swedish CArdioPulmonary BioImage study measured lung function, emphysema, coronary CT angiography, coronary calcium, carotid plaques and ankle-brachial index in 29,593 men and women aged 50-64 years. The results were confirmed using 2-sample Mendelian randomization. Lower lung function and emphysema were associated with more atherosclerosis, but these relationships were attenuated after adjustment for cardiovascular risk factors. Lung function was not associated with coronary atherosclerosis in 14,524 never-smokers. No potentially causal effect of lung function on atherosclerosis, or vice versa, was found in the 2-sample Mendelian randomization analysis. Here we show that reduced lung function and atherosclerosis are correlated in the population, but probably not causally related. Assessing lung function in addition to conventional cardiovascular risk factors to gauge risk of subclinical atherosclerosis is probably not meaningful, but low lung function found by chance should alert for atherosclerosis.

Automated Coronary Artery Calcium and Quantitative Emphysema in Lung Cancer Screening: Association With Mortality, Lung Cancer Incidence, and Airflow Obstruction

PURPOSE

To assess automated coronary artery calcium (CAC) and quantitative emphysema (percentage of low attenuation areas [%LAA]) for predicting mortality and lung cancer (LC) incidence in LC screening. To explore correlations between %LAA, CAC, and forced expiratory value in 1 second (FEV 1 ) and the discriminative ability of %LAA for airflow obstruction.

MATERIALS AND METHODS

Baseline low-dose computed tomography scans of the BioMILD trial were analyzed using an artificial intelligence software. Univariate and multivariate analyses were performed to estimate the predictive value of %LAA and CAC. Harrell C -statistic and time-dependent area under the curve (AUC) were reported for 3 nested models (Model survey : age, sex, pack-years; Model survey-LDCT : Model survey plus %LAA plus CAC; Model final : Model survey-LDCT plus selected confounders). The correlations between %LAA, CAC, and FEV 1 and the discriminative ability of %LAA for airflow obstruction were tested using the Pearson correlation coefficient and AUC-receiver operating characteristic curve, respectively.

RESULTS

A total of 4098 volunteers were enrolled. %LAA and CAC independently predicted 6-year all-cause (Model final hazard ratio [HR], 1.14 per %LAA interquartile range [IQR] increase [95% CI, 1.05-1.23], 2.13 for CAC ≥400 [95% CI, 1.36-3.28]), noncancer (Model final HR, 1.25 per %LAA IQR increase [95% CI, 1.11-1.37], 3.22 for CAC ≥400 [95%CI, 1.62-6.39]), and cardiovascular (Model final HR, 1.25 per %LAA IQR increase [95% CI, 1.00-1.46], 4.66 for CAC ≥400, [95% CI, 1.80-12.58]) mortality, with an increase in concordance probability in Model survey-LDCT compared with Model survey ( P <0.05). No significant association with LC incidence was found after adjustments. Both biomarkers negatively correlated with FEV 1 ( P <0.01). %LAA identified airflow obstruction with a moderate discriminative ability (AUC, 0.738).

CONCLUSIONS

Automated CAC and %LAA added prognostic information to age, sex, and pack-years for predicting mortality but not LC incidence in an LC screening setting. Both biomarkers negatively correlated with FEV 1 , with %LAA enabling the identification of airflow obstruction with moderate discriminative ability.

The Role of Oxidative Stress and Antioxidants in Cardiovascular Comorbidities in COPD

Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in disease pathomechanisms. Unbalance between oxidants and antioxidant defense mechanisms amplifies the local inflammatory processes, worsens cardiovascular health, and contributes to COPD-related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures, with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced, with some suggestions for further research in the field.

Endothelial dysfunction: The possible link between cardiovascular comorbidities and phenomenon of inflammaging from COPD

Aging is a risk factor for many chronic noncommunicable diseases, including chronic obstructive pulmonary disease (COPD), which is often associated with cardiovascular disease (CVD). Moreover, aging is associated with a mild form of systemic inflammation. The aim of our study was to analyze the relationship between age, systemic and vascular inflammation, and the presence of CVD comorbidities in a stable COPD population. Forty COPD patients were divided into 2 age groups (<65 and ≥65 years of age), from which we collected the following inflammatory biomarkers: C-reactive protein, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and endothelin-1 (ET-1). Elderly COPD patients had more frequent exacerbation events per year (2 vs 1, P = .06), a higher prevalence of CVD (3 vs 2, P = .04), more limited exercise tolerance (6-minute walking test distance, 343 [283-403] vs 434 [384-484]; P = .02), and mild systemic inflammation (TNF-α, 9.02 [7.08-10.96] vs 6.48 [5.21-7.76]; P = .03; ET-1, 2.24 [1.76-2.71] vs 1.67 [1.36-1.98] pg/mL; P = .04). A weak correlation between age and ET-1 (r = 0.32, P = .04) was observed. Mild systemic inflammation, characterized by a slightly increased level of TNF-α, and endothelial dysfunction, marked by elevated ET-1, could be liaisons between aging, COPD, and CVD comorbidities.

Effect Analysis of Lung Rehabilitation Training in 5A Nursing Mode for Elderly Patients with COPD Based on X-Ray

This study was aimed at evaluating the application effect of pulmonary rehabilitation training under 5A nursing mode based on X-ray in elderly patients with chronic obstructive pulmonary disease (COPD). Then, 84 elderly patients with chronic obstructive emphysema were selected as the research subjects. COPD knowledge level questionnaire, caregiver self-efficacy scale (CSES), COPD assessment test (CAT), and 6-minute walking experiment (6MWD) were adopted, and the clinical application effect of pulmonary rehabilitation training and conventional nursing under 5A nursing mode was comprehensively compared. The results show that after two and four months of intervention, the average score of COPD knowledge level questionnaire in the test group was 27.43 points and 30.08 points, respectively, higher than that in the control group (P < 0.05). After two and four months of intervention, the number of patients with good compliance in the test group was remarkably improved, and the severity of airflow restriction in the test group was slower than that in the control group. In short, pulmonary rehabilitation training under 5A nursing mode based on X-ray can effectively improve the disease knowledge level, self-efficacy, and pulmonary rehabilitation training compliance of elderly COPD patients, which played an important role in improving the quality of life of patients and alleviating the degree of dyspnea of patients.

Ebselen abolishes vascular dysfunction in influenza A virus-induced exacerbations of cigarette smoke-induced lung inflammation in mice

People with chronic obstructive pulmonary disease (COPD) are susceptible to respiratory infections which exacerbate pulmonary and/or cardiovascular complications, increasing their likelihood of death. The mechanisms driving these complications remain unknown but increased oxidative stress has been implicated. Here we investigated whether influenza A virus (IAV) infection, following chronic cigarette smoke (CS) exposure, worsens vascular function and if so, whether the antioxidant ebselen alleviates this vascular dysfunction. Male BALB/c mice were exposed to either room air or CS for 8 weeks followed by inoculation with IAV (Mem71, 1 × 104.5 pfu). Mice were treated with ebselen (10 mg/kg) or vehicle (5% w/v CM-cellulose in water) daily. Mice were culled 3- and 10-days post-infection, and their lungs lavaged to assess inflammation. The thoracic aorta was excised to investigate endothelial and smooth muscle dilator responses, expression of key vasodilatory and oxidative stress modulators, infiltrating immune cells and vascular remodelling. CS increased lung inflammation and caused significant vascular endothelial dysfunction, which was worsened by IAV infection. CS-driven increases in vascular oxidative stress, aortic wall remodelling and suppression of endothelial nitric oxide synthase (eNOS) were not affected by IAV infection. CS and IAV infection significantly enhanced T cell recruitment into the aortic wall. Ebselen abolished the exaggerated lung inflammation, vascular dysfunction and increased T cell infiltration in CS and IAV-infected mice. Our findings showed that ebselen treatment abolished vascular dysfunction in IAV-induced exacerbations of CS-induced lung inflammation indicating it may have potential for the treatment of cardiovascular comorbidities seen in acute exacerbations of COPD (AECOPD).

Chronic obstructive pulmonary disease and atherosclerosis: common mechanisms and novel therapeutics

Chronic obstructive pulmonary disease (COPD) and atherosclerosis are chronic irreversible diseases, that share a number of common causative factors including cigarette smoking. Atherosclerosis drastically impairs blood flow and oxygen availability to tissues, leading to life-threatening outcomes including myocardial infarction (MI) and stroke. Patients with COPD are most likely to die as a result of a cardiovascular event, with 30% of all COPD-related deaths being attributed to cardiovascular disease (CVD). Both atherosclerosis and COPD involve significant local (i.e. lung, vasculature) and systemic inflammation and oxidative stress, of which current pharmacological treatments have limited efficacy, hence the urgency for the development of novel life-saving therapeutics. Currently these diseases must be treated individually, with no therapies available that can effectively reduce the likelihood of comorbid CVD other than cessation of cigarette smoking. In this review, the important mechanisms that drive atherosclerosis and CVD in people with COPD are explained and we propose that modulation of both the oxidative stress and the inflammatory burden will provide a novel therapeutic strategy to treat both the pulmonary and systemic manifestations related to these diseases.

Associations between lung function and future cardiovascular morbidity and overall mortality in a predominantly First Nations population: a cohort study

Background

Spirometric lung function impairment is an independent predictor of respiratory and cardiovascular disease, and mortality across a broad range of socioeconomic backgrounds and environmental settings. No contemporary studies have explored these relationships in a predominantly regional/remote First Nations population, whose health outcomes are worse than for non-First Nations populations, and First Nations people living in urban centres.

Methods

This was a retrospective cohort study of 1,734 adults (1,113 First Nations) referred to specialist respiratory outreach clinics in the state of Queensland, Australia from February 2012 to March 2020. Regression modelling was used to test associations between lung function and mortality and cardiovascular disease.

Findings

At the time of analysis (August 2020), 189 patients had died: 88 (47%) from respiratory causes and 38 (20%) from cardiovascular causes. When compared to patients with forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC) Z-scores of >0 to -1, patients with Z-scores <-1 were at elevated mortality risk (HR=3•2, 95%CI 1•4-7•4; HR=2•6, 95%CI 1•3-5•1), and elevated cardiovascular disease risk (OR=1•5, 95%CI 1•1-2•2; OR=1•6, 95%CI 1•2-2•3). FEV₁/FVC% Z-scores <-1 were associated with increased overall mortality (HR=1•6, 95%CI 1•1-2•3), but not cardiovascular disease (OR=1•1, 95%CI 0•8-1•4). These associations were not affected by First Nations status.

Interpretation

Reduced lung function even within the clinically normal range is associated with increased mortality, and cardiovascular disease in First Nations Australians. These findings highlight the importance of lung function optimisation and inform the need for future investment to improve outcomes in First Nations populations.

Funding

None.

Associations between respiratory and vascular function in early childhood

BACKGROUND AND OBJECTIVE

The link between respiratory and vascular health is well documented in adult populations. Impaired lung function is consistently associated with thicker arteries and higher incidence of cardiovascular disease. However, there are limited data on this relationship in young children and the studies that exist have focussed on populations at high risk of cardiorespiratory morbidity. We determined if an association exists between respiratory and cardiovascular function in young children and, if so, whether it is confounded by known cardiorespiratory risk factors.

METHODS

Respiratory and vascular data from a prospective cohort study established to evaluate the health implications 3 years after coal mine fire smoke exposure in children aged 3-5 years were used. Respiratory function was measured using the forced oscillation technique and included resistance at 5 Hz (R₅ ), reactance at 5 Hz (X₅ ) and area under the reactance curve (AX). Vascular health was measured by carotid intima-media thickness (ultrasound) and pulse wave velocity (arterial tonometry). Regression analyses were used to examine the relationship between the respiratory Z-scores and cardiovascular measures. Subsequent analyses were adjusted for potential confounding by maternal smoking during pregnancy, maternal education and exposure to fine particulate matter <2.5 μm in aerodynamic diameter (PM_2.5 ).

RESULTS

Peripheral lung function (X₅ and AX), but not respiratory system resistance (R₅ ), was associated with vascular function. Adjustment for maternal smoking, maternal education and early life exposure to PM_2.5 had minimal effect on these associations.

CONCLUSION

These observations suggest that peripheral lung stiffness is associated with vascular stiffness and that this relationship is established early in life.

The Role of ABC Transporters in Lipid Metabolism and the Comorbid Course of Chronic Obstructive Pulmonary Disease and Atherosclerosis

Chronic obstructive pulmonary disease (COPD) ranks among the leading causes of morbidity and mortality worldwide. COPD rarely occurs in isolation and is often combined with various diseases. It is considered that systemic inflammation underlies the comorbid course of COPD. The data obtained in recent years have shown the importance of violations of the cross-links of lipid metabolism and the immune response, which are links in the pathogenesis of both COPD and atherosclerosis. The role of lipid metabolism disorders in the pathogenesis of the comorbid course of COPD and atherosclerosis and the participation of ATP-binding cassette (ABC) transporters in these processes is discussed in this article. It is known that about 20 representatives of a large family of ABC transporters provide lipid homeostasis of cells by moving lipids inside the cell and in its plasma membrane, as well as removing lipids from the cell. It was shown that some representatives of the ABC-transporter family are involved in various links of the pathogenesis of COPD and atherosclerosis, which can determine their comorbid course.

Vascular endothelial damage in COPD: current functional assessment methods and future perspectives

Introduction: Cardiovascular disease is a major cause of death in chronic obstructive pulmonary disease (COPD), but the relationship between these two entities is not fully understood; smoking, inflammation, arterial stiffness and endothelial dysfunction are significant determinants. Endothelial dysfunction is not only associated with cardiovascular disease, but also with COPD severity.Areas covered: Several functional methods have been developed to evaluate endothelial function in healthy and diseased individuals; from the invasive angiography of epicardial coronary arteries and Venous-Occlusion-Plethysmography, to more modern, noninvasive approaches such as Flow-Mediated-Dilatation, Peripheral-Arterial-Tonometry and Near-Infrared-Spectroscopy, all these methods have boosted clinical research in this field. In this context, this narrative review, which included articles published in PubMed and Scopus up to 25-November-2020, summarizes available functional methods for endothelial damage assessment in COPD and discusses existing evidence on their associations with comorbidities and outcomes in this population.Expert opinion: Accumulated evidence suggests that endothelial dysfunction occurs in early stages of CΟPD and worsens with pulmonary obstruction severity and during acute exacerbations. Novel methods evaluating endothelial function offer a detailed, real-time assessment of different parameters related to vascular function and should be increasingly used to shed more light on the role of endothelial damage on cardiovascular and COPD progression.

Association Between Airflow Limitation and Carotid Intima-Media Thickness in the Japanese Population

Purpose

This study aimed to reveal the association between airflow limitation (AL) and carotid intima-media thickness (IMT) according to smoking status in Japan.

Subjects and Methods

This cross-sectional study was performed in 2809 subjects, who underwent a comprehensive health examination with pulmonary function tests and carotid ultrasonographic measurement. AL was defined as forced expiratory volume in 1 s/forced vital capacity of <0.7. The subjects were divided into the following four groups: never smokers without AL, never smokers with AL, former/current smokers without AL, and former/current smokers with AL. Mean IMT, the maximum measurable IMT value in the left and right common carotid arteries (IMT-C max), and mean IMT-C max were measured by carotid ultrasonography. The carotid wall thickness as defined as follows: IMT ≥ 1.1 mm (IMT_1.1), IMT-C max ≥ 1.2 mm (IMTc_1.2), and IMT-C max > 1.5 mm (IMTc_1.5), based on each measured region. The association between AL and the carotid wall thickness according to smoking status was assessed by logistic regression analysis.

Results

The mean carotid IMT and mean IMT-C max were significantly higher in never smokers with AL and former/current smokers with or without AL than in never smokers without AL. In logistic regression models adjusted for sex, age, body mass index, hypertension, dyslipidemia, hyperglycemia, physical activity, and alcohol consumption, the risk of carotid wall thickness (IMT_1.1 [odds ratio {OR}: 1.55; 95% confidence interval {CI}: 1.07-2.24]; IMTc_1.2 [OR: 1.52; 95% CI: 1.03-2.24]; IMTc_1.5 [OR: 1.99; 95% CI: 1.15-3.46]) were significantly higher in former/current smokers with AL than in never smokers without AL.

Conclusion

The present results suggest that greater IMT and risk of carotid wall thickness were associated with AL and smoking experience.

Prevalence of different comorbidities in chronic obstructive pulmonary disease among Shahrekord PERSIAN cohort study in southwest Iran

Comorbidities are common in chronic obstructive pulmonary disease (COPD) patients. This study was conducted to determine the prevalence of common comorbidities in patients with COPD compared with people without COPD. This cross-sectional, population-based study was performed on 6961 adults aged 35-70 years enrolled in the Shahrekord PERSIAN cohort study. Data (demographic and clinical characteristics, comorbidities, anthropometric and blood pressure measurements, laboratory, and spirometry tests) collection was performed according to the cohort protocol from 2015 to 2019. In the present study, 215 (3.1%) patients were diagnosed with COPD and 1753 (25.18%) ones with restrictive lung patterns. The mean age of COPD patients was 52.5 ± 9.76 years. 55.8% of patients were male, 17.7% were current smokers and 12.1% had a history of smoking or were former smokers. 5.6% of patients had no comorbidity and 94.5% had at least one comorbidity. The most common comorbidities in COPD patients were dyslipidemia (70.2%), hypertension (30.2%), metabolic syndrome (22.8%), and diabetes (16.7%). The most common comorbidities in individuals with a restrictive spirometry pattern were dyslipidemia (68.9%), metabolic syndrome (27.2%), hypertension (26.1%), depression (17.6%), and fatty liver (15.5%). The logistic regression analysis with 95% confidence interval (95%CI) of odds ratio (OR) showed that comorbidities of chronic lung diseases (OR = 2.12, 95% CI 1.30-3.44), diabetes (OR = 1.54, 95%CI 1.03-2.29), cardiovascular disease (OR = 1.52, 95%CI 1.17-2.43), and hypertension (OR = 1.4, 95%CI 1.02-1.99) were more likely to occur in COPD patients than in healthy individuals. Knowing these prevalence rates and related information provides new insights on comorbidities to reduce disease burden and develop preventive interventions and to regulate health care resources to meet the needs of patients in primary health care.

Association Between Systemic and Pulmonary Vascular Dysfunction in COPD

Introduction

In chronic obstructive pulmonary disease (COPD), endothelial dysfunction and stiffness of systemic arteries may contribute to increased cardiovascular risk. Pulmonary vascular disease (PVD) is frequent in COPD. The association between PVD and systemic vascular dysfunction has not been thoroughly evaluated in COPD.

Methods

A total of 108 subjects were allocated into four groups (non-smoking controls, smoking controls, COPD without PVD and COPD with PVD). In systemic arteries, endothelial dysfunction was assessed by flow-mediated dilation (FMD) and arterial stiffness by pulse wave analysis (PWA) and pulse wave velocity (PWV). PVD was defined by a mean pulmonary artery pressure (PAP) ≥25 mmHg at right heart catheterization or by a tricuspid regurgitation velocity >2.8 m/s at doppler echocardiography. Biomarkers of inflammation and endothelial damage were assessed in peripheral blood.

Results

FMD was lower in COPD patients, with or without PVD, compared to non-smoking controls; and in patients with COPD and PVD compared to smoking controls. PWV was higher in COPD with PVD patients compared to both non-smoking and smoking controls in a model adjusted by age and the Framingham score; PWV was also higher in patients with COPD and PVD compared to COPD without PVD patients in the non-adjusted analysis. FMD and PWV correlated significantly with forced expiratory volume in the first second (FEV₁), diffusing capacity for carbon monoxide (DL_CO) and systolic PAP. FMD and PWV were correlated in all subjects.

Discussion

We conclude that endothelial dysfunction of systemic arteries is common in COPD, irrespective if they have PVD or not. COPD patients with PVD show increased stiffness and greater impairment of endothelial function in systemic arteries. These findings suggest the association of vascular impairment in both pulmonary and systemic territories in a subset of COPD patients.

Herpud1 deficiency could reduce amyloid-β40 expression and thereby suppress homocysteine-induced atherosclerosis by blocking the JNK/AP1 pathway

Homocysteine (Hcy) is considered an independent risk factor for various cardiovascular diseases including atherosclerosis which is associated with lipid metabolism, inflammation, and oxidative stress. Results from our previous study suggested that Hcy-induced atherosclerosis could be reversed by Herpud1 knockout which inhibits vascular smooth muscle cell (VSMC) phenotype switching. Here, we aim to investigate more precise mechanisms behind the improvement in Hcy-induced atherosclerosis. Amyloid-β40 (Aβ40), a vital protein in Alzheimer disease (AD), has been regarded as an important component in the atherosclerosis program in recent years due to the biological similarity between AD and atherosclerosis. Thus, we determined to assess the value of Aβ40 in a Herpud1 knockout Hcy-induced atherosclerosis mouse model by measuring Aβ40 expression in tissue and biomarkers of lipid metabolism, inflammation, and oxidative stress in serum. Additionally, since endothelial dysfunction plays a prominent role in atherosclerosis, we tested human umbilical vein endothelial cell (HUVEC) function following Herpud1 silencing in vitro and evaluated JNK/AP1 signaling activation in our models because of its close relationship with Aβ40. As a result, our animal models showed that Herpud1 knockout reduced Aβ40 expression, inflammation, and oxidative stress levels other than lipid metabolism and alleviated atherosclerosis via JNK/AP1 signaling inhibition. Similarly, our cell experiments implied that Hcy-induced Aβ40 elevation and HUVEC dysfunction involving cell proliferation and apoptosis could be restored by Herpud1 silence through restraining JNK/AP1 pathway. Collectively, our study demonstrates that Herpud1 deficiency could reduce Aβ40 expression, thereby suppressing Hcy-induced atherosclerosis by blocking the JNK/AP1 pathway. This may provide novel potential targets for atherosclerosis prevention or treatment.

The Potential Effects of Policy-driven Air Pollution Interventions on Childhood Lung Development

Rationale: Although elevated air pollution exposure impairs lung-function development in childhood, it remains a challenge to use this information to estimate the potential public health benefits of air pollution interventions in exposed populations.Objectives: Apply G-computation to estimate hypothetical effects of several realistic scenarios for future air pollution reductions on lung growth.Methods: Mixed-effects linear regression was used to estimate FEV1 and FVC from age 11 to 15 years in 2,120 adolescents across 3 cohorts (1993-2001, 1997-2004, and 2007-2011). Models included regional pollutants (nitrogen dioxide [NO2] or particulate matter with an aerodynamic diameter ≤2.5 μm [PM2.5]) and other important covariates. Using G-computation, a causal inference-based method, we then estimated changes in mean lung growth in our population for hypothetical interventions on either NO2 or PM2.5. Confidence intervals (CIs) were computed by bootstrapping (N = 1,000).Measurements and Main Results: Compared with the effects of exposure from observed NO2 concentrations during the study period, had communities remained at 1994 to 1997 NO2 levels, FEV1 and FVC growth were estimated to have been reduced by 2.7% (95% CI, -3.6 to -1.8) and 4.2% (95% CI, -5.2 to -3.4), respectively. If NO2 concentrations had been reduced by 30%, we estimated a 4.4% increase in FEV1 growth (95% CI, 2.8-5.9) and a 7.1% increase in FVC growth (95% CI, 5.7-8.6). Comparable results were observed for PM2.5 interventions.Conclusions: We estimated that substantial increases in lung function would occur as a result of interventions that reduce NO2 or PM2.5 concentrations. These findings provide a quantification of potential health benefits of air quality improvement.

Loss of skin elasticity is associated with pulmonary emphysema, biomarkers of inflammation, and matrix metalloproteinase activity in smokers

BACKGROUND

Elastin breakdown and the resultant loss of lung elastic recoil is a hallmark of pulmonary emphysema in susceptible individuals as a consequence of tobacco smoke exposure. Systemic alterations to the synthesis and degradation of elastin may be important to our understanding of disease phenotypes in chronic obstructive pulmonary disease. We investigated the association of skin elasticity with pulmonary emphysema, obstructive lung disease, and blood biomarkers of inflammation and tissue protease activity in tobacco-exposed individuals.

METHODS

Two hundred and thirty-six Caucasian individuals were recruited into a sub-study of the University of Pittsburgh Specialized Center for Clinically Orientated Research in chronic obstructive pulmonary disease, a prospective cohort study of current and former smokers. The skin viscoelastic modulus (VE), a determinant of skin elasticity, was recorded from the volar forearm and facial wrinkling severity was determined using the Daniell scoring system.

RESULTS

In a multiple regression analysis, reduced VE was significantly associated with cross-sectional measurement of airflow obstruction (FEV1/FVC) and emphysema quantified from computed tomography (CT) images, β = 0.26, p = 0.001 and β = 0.24, p = 0.001 respectively. In emphysema-susceptible individuals, elasticity-determined skin age was increased (median 4.6 years) compared to the chronological age of subjects without emphysema. Plasma biomarkers of inflammation (TNFR1, TNFR2, CRP, PTX3, and SAA) and matrix metalloproteinase activity (MMP1, TIMP1, TIMP2, and TIMP4) were inversely associated with skin elasticity.

CONCLUSIONS

We report that an objective non-invasive determinant of skin elasticity is independently associated with measures of lung function, pulmonary emphysema, and biomarkers of inflammation and tissue proteolysis in tobacco-exposed individuals. Loss of skin elasticity is a novel observation that may link the common pathological processes that drive tissue elastolysis in the extracellular matrix of the skin and lung in emphysema-susceptible individuals.

Lung Function, Coronary Artery Disease, and Mortality in HIV

Rationale: Impaired lung function is a potent independent predictor of coronary artery disease (CAD) in individuals without human immunodeficiency virus (HIV) infection; however, the relationship between lung function and CAD in HIV remains undefined. Objectives: To examine the relationship between lung function, CAD, mortality, and circulating biomarkers in HIV. Methods: Spirometry, diffusing capacity of the lung for carbon monoxide (DlCO), emphysema, coronary artery calcium, mortality, cause of death, and biomarkers were examined in HIV-infected and uninfected individuals enrolled in a cohort study at the University of Pittsburgh. Results were then validated in the Multicenter AIDS Cohort Study (MACS) cohort. Results: We examined data on 234 participants in the Pittsburgh cohort. The mean ± standard deviation age was 49.5 ± 10.2 years old, 82.1% were male, and 67.5% were ever smokers. Among the 177 of 234 individuals with HIV infection, lower DlCO (not forced expiratory volume in 1 second or emphysema) was independently associated with greater coronary artery calcium (odds ratio, 1.43 per 10% lower DlCO; 95% confidence interval, 1.14-1.81). HIV-infected individuals with both reduced DlCO and coronary artery calcium had a much higher mortality than those with either low DlCO or coronary calcium alone or with neither condition. Endothelin-1, a circulating biomarker of endothelial dysfunction, was associated with both lower DlCO and greater coronary artery calcium in those with HIV infection. Results were reproducible in 144 individuals enrolled in the MACS cohort; intercellular adhesion molecule 1 was the biomarker of endothelial dysfunction assessed in the MACS cohort. Conclusions: Impaired DlCO and CAD were associated with each other and with higher mortality in individuals with HIV infection.

Endothelial dysfunction in patients with chronic obstructive pulmonary disease in combination with coronary heart disease

AIM

The aim of this study was to evaluate the state of the vascular wall in patients with chronic obstructive pulmonary disease (COPD) combined with chronic coronary artery disease (CAD).

MATERIALS AND METHODS

The study included 108 patients: 37 patients with COPD and CAD and 71 patients with COPD without CAD. Endothelial function was studied in tests with reactive hyperemia and nitroglycerin. The number of blood plasma desquamated endotheliocytes were determined by the Hladovec method. In patients with COPD identified are signs of vascular wall remodeling: thickening wall of the brachial artery, reduction of the flow-mediated vasodilation. Patients with COPD in combination with CHD demonstrated higher impairments of the vasoregulatory dysfunction of endothelial of the vascular wall.

RESULTS

CONCLUSION

In patients with COPD combined with chronic coronary heart disease more pronounced endothelial dysfunction with disturbance of endothelium-dependent vasomotor reactions.

Reduced axial diffusivity and increased mode and T2 signals in cerebral white matter of chronic obstructive pulmonary disease using tract-based spatial statistics

PURPOSE

Chronic obstructive pulmonary disease (COPD) is considered to be a multi-systemic disease involving pathological changes in the brain. This study investigated how diffusion tensor imaging (DTI) parameters in patients with non-hypoxemic COPD differ from those in controls. Moreover, we tried to examine whether the mode of anisotropy (MO) reflects early changes in white matter (WM) integrity in COPD.

METHODS

DT images were obtained from 13 male COPD patients and 13 age- and sex-matched healthy controls. Raw DT images were processed using an automated tract-based spatial statistics (TBSS) pipeline. DTI scalars of fractional anisotropy (FA); axial, radial, and mean diffusivities (AD, RD, and MD, respectively); MO; and raw T2 signal (S0) were statistically compared between COPD patients and controls. TBSS methods were used for analysis.

RESULTS

In patients with COPD, decreased AD was observed in the temporal stem (TS), corticospinal tract (CST), thalamus, subiculum, crus cerebri, and midbrain. Increased MO values were found in the corpus callosum, CST, internal capsule, cerebellar peduncle (CP), and medial lemniscus (ML). Additionally, increased S0 was found in the TS, CP, pons, and cerebellar tonsil (threshold-free cluster enhancement to a family-wise error rate of p < 0.05).

CONCLUSION

The results revealed decreased AD and increased MO scalars in COPD patients compared with the controls, although there were no differences in FA, RD, and MD scalars. Decreased AD and increased MO scalars may reflect early changes in WM integrity in COPD patients.

Albuminuria, Lung Function Decline, and Risk of Incident Chronic Obstructive Pulmonary Disease. The NHLBI Pooled Cohorts Study

RATIONALE

Chronic lower respiratory diseases (CLRDs), including chronic obstructive pulmonary disease (COPD) and asthma, are the fourth leading cause of death. Prior studies suggest that albuminuria, a biomarker of endothelial injury, is increased in patients with COPD.

OBJECTIVES

To test whether albuminuria was associated with lung function decline and incident CLRDs.

METHODS

Six U.S. population-based cohorts were harmonized and pooled. Participants with prevalent clinical lung disease were excluded. Albuminuria (urine albumin-to-creatinine ratio) was measured in spot samples. Lung function was assessed by spirometry. Incident CLRD-related hospitalizations and deaths were classified via adjudication and/or administrative criteria. Mixed and proportional hazards models were used to test individual-level associations adjusted for age, height, weight, sex, race/ethnicity, education, birth year, cohort, smoking status, pack-years of smoking, renal function, hypertension, diabetes, and medications.

MEASUREMENTS AND MAIN RESULTS

Among 10,961 participants with preserved lung function, mean age at albuminuria measurement was 60 years, 51% were never-smokers, median albuminuria was 5.6 mg/g, and mean FEV1 decline was 31.5 ml/yr. For each SD increase in log-transformed albuminuria, there was 2.81% greater FEV1 decline (95% confidence interval [CI], 0.86-4.76%; P = 0.0047), 11.02% greater FEV1/FVC decline (95% CI, 4.43-17.62%; P = 0.0011), and 15% increased hazard of incident spirometry-defined moderate-to-severe COPD (95% CI, 2-31%, P = 0.0021). Each SD log-transformed albuminuria increased hazards of incident COPD-related hospitalization/mortality by 26% (95% CI, 18-34%, P < 0.0001) among 14,213 participants followed for events. Asthma events were not significantly associated. Associations persisted in participants without current smoking, diabetes, hypertension, or cardiovascular disease.

CONCLUSIONS

Albuminuria was associated with greater lung function decline, incident spirometry-defined COPD, and incident COPD-related events in a U.S. population-based sample.

Centrilobular emphysema and coronary artery calcification: mediation analysis in the SPIROMICS cohort

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with a two-to-five fold increase in the risk of coronary artery disease independent of shared risk factors. This association is hypothesized to be mediated by systemic inflammation but this link has not been established.

METHODS

We included 300 participants enrolled in the SPIROMICS cohort, 75 each of lifetime non-smokers, smokers without airflow obstruction, mild-moderate COPD, and severe-very severe COPD. We quantified emphysema and airway disease on computed tomography, characterized visual emphysema subtypes (centrilobular and paraseptal) and airway disease, and used the Weston visual score to quantify coronary artery calcification (CAC). We used the Sobel test to determine whether markers of systemic inflammation mediated a link between spirometric and radiographic features of COPD and CAC.

RESULTS

FEV1/FVC but not quantitative emphysema or airway wall thickening was associated with CAC (p = 0.036), after adjustment for demographics, diabetes mellitus, hypertension, statin use, and CT scanner type. To explain this discordance, we examined visual subtypes of emphysema and airway disease, and found that centrilobular emphysema but not paraseptal emphysema or bronchial thickening was independently associated with CAC (p = 0.019). MMP3, VCAM1, CXCL5 and CXCL9 mediated 8, 8, 7 and 16% of the association between FEV1/FVC and CAC, respectively. Similar biomarkers partially mediated the association between centrilobular emphysema and CAC.

CONCLUSIONS

The association between airflow obstruction and coronary calcification is driven primarily by the centrilobular subtype of emphysema, and is linked through bioactive molecules implicated in the pathogenesis of atherosclerosis.

TRIAL REGISTRATION

ClinicalTrials.gov: Identifier: NCT01969344 .

Environmental exposures and systemic hypertension are risk factors for decline in lung function

BACKGROUND

Chronic lung disease is a leading contributor to the global disease burden; however, beyond tobacco smoke, we do not fully understand what risk factors contribute to lung function decline in low-income and middle-income countries.

METHODS

We collected sociodemographic and clinical data in a randomly selected, age-stratified, sex-stratified and site-stratified population-based sample of 3048 adults aged ≥35 years from four resource-poor settings in Peru. We assessed baseline and annual pre-bronchodilator and post-bronchodilator lung function over 3 years. We used linear mixed-effects models to assess biological, socioeconomic and environmental risk factors associated with accelerated lung function decline.

RESULTS

Mean±SD enrolment age was 55.4±12.5 years, 49.2% were male and mean follow-up time was 2.36 (SD 0.61) years. Mean annual pre-bronchodilator FEV1 decline was 30.3 mL/year (95% CI 28.6 to 32.0) and pre-bronchodilator FVC decline was 32.2 mL/year (30.0 to 34.4). Using multivariable linear mixed-effects regression, we found that urban living, high-altitude dwelling and having hypertension accounted for 25.9% (95% CI 15.7% to 36.1%), 21.3% (11.1% to 31.5%) and 15.7% (3.7% to 26.9%) of the overall mean annual decline in pre-bronchodilator FEV1/height2, respectively. Corresponding estimates for pre-bronchodilator FVC/height2 were 42.1% (95% CI% 29.8% to 54.4%), 36.0% (23.7% to 48.2%) and 15.8% (2.6% to 28.9%) of the overall mean annual decline, respectively.

CONCLUSION

Urbanisation, living at high altitude and hypertension were associated with accelerated lung function decline in a population with low daily smoking prevalence.

The SCFFBXO3 ubiquitin E3 ligase regulates inflammation in atherosclerosis

Inflammation is critical in the pathobiology of atherosclerosis. An essential player in the inflammatory process in atherosclerosis are macrophages that scavenge oxidatively modified low-density lipoproteins (OxLDL) deposited in the subendothelium of systemic arteries that secrete a myriad of pro-inflammatory mediators. Here, we identified that a subunit of the Skp-Cullin-F-box ubiquitin E3 ligase apparatus, termed FBXO3, modulates the inflammatory response in atherosclerosis. Specifically, individuals with a hypofunctioning genetic variant of FBXO3 develop less atherosclerosis. FBXO3 protein is present in cells of monocytic lineage within carotid plaques and its levels increase in those with symptomatic compared with asymptomatic atherosclerosis. Further, cellular depletion or small molecule inhibition of FBXO3 significantly reduced the inflammatory response to OxLDL by macrophages without altering OxLDL uptake. Thus, FBXO3 potentiates vascular inflammation and atherosclerosis that can be effectively mitigated by a small molecule inhibitor.

Decreased serum TRAIL is associated with increased mortality in smokers with comorbid emphysema and coronary artery disease

BACKGROUND

Smokers are highly susceptible to lung and cardiovascular disease that can reduce their survival. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a protein in the circulation that may suppress vascular and pulmonary inflammation. Therefore, we hypothesized that diminished circulating TRAIL levels would be associated with poor survival in smokers with lung and cardiovascular disease.

METHODS

Serum TRAIL level was measured by immunoassay in 474 smokers. Coronary atherosclerosis was assessed by coronary artery calcium scoring along with emphysema, lung function, and survival.

RESULTS

The 474 smokers were 65.7 ± 6.3 years old and 52.2% male with 55.3 ± 31.5 pack-years of tobacco-exposure. 83 of them died during 3588.2 person-years of follow up. At baseline, lower TRAIL level was associated with more coronary artery calcium (OR = 1.2 per SD, 95%CI 1.1-1.5, p = 0.02), and with history of myocardial infarction (OR = 2.3 per SD, 95%CI 1.2-4.5, p = 0.02), angina (OR = 1.6 per SD, 95%CI 1.1-2.6, p = 0.03), and angioplasty (OR = 1.8 per SD, 95%CI 1.0-3.1, p = 0.04) in models adjusted for cardiovascular risk-factors, FEV₁, and emphysema. Also, lower TRAIL level was associated with emphysema severity independent of demographics and tobacco exposure (β = 0.11 sq. root units, 95% CI 0.01-0.22, p = 0.03). Further, TRAIL level was lowest in smokers with comorbid emphysema and coronary artery calcification rather than either condition alone. Finally, lower TRAIL level was independently associated with increased mortality in smokers particularly in those with comorbid emphysema and coronary artery calcification (HR = 1.38, 95% CI 1.01-1.90).

CONCLUSIONS

TRAIL level is reduced in smokers with comorbid emphysema and coronary artery disease, and is associated with reduced survival.

Endothelial dysfunction is associated with impaired lung function in two independent community cohorts

BACKGROUND

Prior studies investigating the association between endothelial dysfunction and impaired lung function have been small and inconsistent. The primary aim was to investigate the association between endothelial function and lung function in two community-based cohorts.

METHODS

We used a discovery/replication approach to study the association between endothelial function and lung function in the Prospective investigation of Obesity, Energy and Metabolism (POEM, discovery cohort, n = 490, mean age 50.3 ± 0.2 years) and the Prospective Study of the Vasculature in Uppsala Seniors (PIVUS, replication cohort, n = 892, mean age 70.2 ± 0.15 years). Spirometry and three different measures of endothelial function were performed including both the invasive forearm technique (endothelium-dependent and endothelium-independent vasodilation [EDV and EIDV, respectively] and noninvasive flow mediated dilation [FMD]).

RESULTS

An age and sex adjusted association between lower EDV and lower FEV₁ was found in POEM and replicated in PIVUS. After merging the two cohorts, 1 standard deviation decrease in EDV was associated with 1.57% lower FEV₁ after additional adjustment for smoking status, body mass index, exercise level, and C-reactive protein (95% confidence intervals 0.63-2.51, p = 0.001). The association was slightly lower albeit still statistically significant after excluding participants without cardiovascular disease and chronic respiratory disease and appeared stronger among previous/current smokers vs. non-smokers and in men vs. women (p for interaction = 0.2 and 0.02 respectively).

CONCLUSIONS

Our findings suggest that even individuals with sub-clinical impairments of lung function in the community have concomitant endothelial dysfunction.

Genome-wide assessment of gene-by-smoking interactions in COPD

Cigarette smoke exposure is a major risk factor in chronic obstructive pulmonary disease (COPD) and its interactions with genetic variants could affect lung function. However, few gene-smoking interactions have been reported. In this report, we evaluated the effects of gene-smoking interactions on lung function using Korea Associated Resource (KARE) data with the spirometric variables—forced expiratory volume in 1 s (FEV₁). We found that variations in FEV₁ were different among smoking status. Thus, we considered a linear mixed model for association analysis under heteroscedasticity according to smoking status. We found a previously identified locus near SOX9 on chromosome 17 to be the most significant based on a joint test of the main and interaction effects of smoking. Smoking interactions were replicated with Gene-Environment of Interaction and phenotype (GENIE), Multi-Ethnic Study of Atherosclerosis-Lung (MESA-Lung), and COPDGene studies. We found that individuals with minor alleles, rs17765644, rs17178251, rs11870732, and rs4793541, tended to have lower FEV₁ values, and lung function decreased much faster with age for smokers. There have been very few reports to replicate a common variant gene-smoking interaction, and our results revealed that statistical models for gene-smoking interaction analyses should be carefully selected.

High prevalence of COPD in atherosclerosis patients

Atherosclerosis and COPD are both systemic inflammatory diseases that may influence each other. The aim of the present study was to determine the prevalence of COPD in patients with cerebral and/or peripheral artery disease and to assess factors associated with the presence of COPD. Following the diagnosis of cerebral and/or peripheral artery disease by means of duplex sonography, 166 consecutive patients underwent body plethysmography with capillary blood gas analysis. Thereafter, blood tests with determination of different parameters such as lipid profile, inflammatory and coagulation markers were conducted in remaining 136 patients who fulfilled inclusion criteria of the study. Thirty-six out of 136 patients suffered from COPD, mostly in early stages of the disease. Residual volume indicating emphysema was increased (162.9%±55.9% vs 124.5%±37.0%, p<0.05) and diffusion capacity was decreased (55.1%±19.5% vs 75.3%±18.6%, p<0.05) in COPD patients vs non-COPD group. In capillary blood gas analysis, COPD patients had lower partial pressure of oxygen (70.9±11.5 vs 75.2±11.0 mmHg, p<0.05) and higher partial pressure of carbon dioxide (36.8±7.5 vs 34.4±4.4 mmHg, p<0.05) compared with non-COPD individuals. Presence of COPD was associated with predominance of diabetes mellitus, interleukin-8-related systemic neutrophilic inflammation and anemia. In conclusion, COPD is highly prevalent in patients with atherosclerotic artery disease.

Investigation of the relationship between asthma and subclinical atherosclerosis by carotid/femoral intima media and epicardial fat thickness measurement

OBJECTIVE

Since asthma and atherosclerosis may share similar pathophysiological mechanism, this study is planned to investigate whether epicardial fat thickness (EFT), carotid and femoral intima media thicknesses, which are markers of subclinical atherosclerosis, are increased in patients with asthma.

METHODS

The study was designed as a cross-sectional study. A total of 154 participants (83 patients with asthma and 71 healthy volunteers) were enrolled into the study. Epicardial fat, carotid, and femoral intima media thicknesses were measured and recorded in both groups. The statistical difference between the two groups was examined.

RESULTS

Both carotid and femoral intima media thicknesses were significantly higher in patients with asthma compared to control group (5.52 ± 0.4 mm vs. 5.36 ± 0.4 mm; p = 0.038 and 5.64 ± 0.4 mm vs. 5.46 ± 0.5 mm; p = 0.036, respectively). However, there was not a significant difference in EFT between the groups [5.9 mm (5.3-6.6; IQR = 1.3) vs. 5.6 mm (4.7-6.5; IQR = 1.8); p = 0.1]. On comparison of control group and asthma subgroups (mild, moderate, and severe), there was a statistically significant difference among these four groups in terms of carotid and femoral intima media thicknesses (p = 0.002 and p < 0.001, respectively). Subgroup analyses showed that this difference was mainly due to patients with severe asthma.

CONCLUSIONS

Carotid and femoral intima media thicknesses in asthmatic patients were found to be increased compared to the normal population. As a result, the risk of subclinical atherosclerosis in asthmatic patients may be high.

Paradigms in chronic obstructive pulmonary disease: phenotypes, immunobiology, and therapy with a focus on vascular disease

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous syndrome that represents a major global health burden. COPD phenotypes have recently emerged based on large cohort studies addressing the need to better characterize the syndrome. Though comprehensive phenotyping is still at an early stage, factors such as ethnicity and radiographic, serum, and exhaled breath biomarkers have shown promise. COPD is also an immunological disease where innate and adaptive immune responses to the environment and tobacco smoke are altered. The frequent overlap between COPD and other systemic diseases, such as cardiovascular disease, has influenced COPD therapy, and treatments for both conditions may lead to improved patient outcomes. Here, we discuss current paradigms that center on improving the definition of COPD, understanding the immunological overlap between COPD and vascular inflammation, and the treatment of COPD-with a focus on comorbid cardiovascular disease.

GDF-15 plasma levels in chronic obstructive pulmonary disease are associated with subclinical coronary artery disease

BACKGROUND

Growth differentiation factor-15 (GDF-15), a cytokine associated with cardiovascular mortality, increases during chronic obstructive pulmonary disease (COPD) exacerbations, but any role in stable COPD is unknown. We tested associations between GDF-15 and subclinical coronary atherosclerosis, assessed by coronary artery calcium (CAC) score, in COPD subjects free of clinical cardiovascular disease (CVD).

METHODS

Cross-sectional analysis of COPD participants (GOLD stages 2-4) in the COPDGene cohort without CVD at enrollment, using baseline CAC (from non-EKG-gated chest computed tomography) and plasma GDF-15 (by custom ELISA). We used multinomial logistic modeling of GDF-15 associations with CAC, adjusting for demographics, baseline risk (calculated using the HEART: Personal Heart Early Assessment Risk Tool (Budoff et al. 114:1761-1791, 2006) score), smoking history, measures of airflow obstruction, emphysema and airway disease severity.

RESULTS

Among 694 participants with COPD (47% women, mean age 63.6 years) mean GDF-15 was 1,304 pg/mL, and mean CAC score was 198. Relative to the lower GDF-15 tertile, higher tertiles showed bivariate association with increasing CAC score (mid tertile odds ratio [OR] 1.80, 95% confidence interval [CI] 1.29, 2.51; higher tertile OR 2.86, CI 2.04, 4.02). This association was maintained after additionally adjusting for baseline CVD risk, for co-morbidities and descriptors of COPD severity and impact, markers of cardiac stress (N-terminal pro-B-type natriuretic peptide, troponin T) and of inflammation (Interleukin-6), and in subgroup analysis excluding men, diabetics, current smokers or those with limited ambulation.

CONCLUSIONS

In ever-smokers with COPD free of clinical CVD, GDF-15 contributes independently to subclinical coronary atherosclerosis.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00608764 . Registered 28 January 2008.

Extracellular Vesicles in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is characterized by the progression of irreversible airflow limitation and is a leading cause of morbidity and mortality worldwide. Although several crucial mechanisms of COPD pathogenesis have been studied, the precise mechanism remains unknown. Extracellular vesicles (EVs), including exosomes, microvesicles, and apoptotic bodies, are released from almost all cell types and are recognized as novel cell–cell communication tools. They have been shown to carry and transfer a wide variety of molecules, such as microRNAs, messenger RNAs, and proteins, which are involved in physiological functions and the pathology of various diseases. Recently, EVs have attracted considerable attention in pulmonary research. In this review, we summarize the recent findings of EV-mediated COPD pathogenesis. We also discuss the potential clinical usefulness of EVs as biomarkers and therapeutic agents for the treatment of COPD.

Morphological changes in small pulmonary vessels are associated with severe acute exacerbation in chronic obstructive pulmonary disease

BACKGROUND

Pulmonary vascular remodeling is essential for understanding the pathogenesis of chronic obstructive pulmonary disease (COPD). The total cross-sectional area (CSA) of small pulmonary vessels has been reported to correlate with the pulmonary artery pressure, and this technique has enabled the assessment of pulmonary vascular involvements. We investigated the contribution of morphological alterations in the pulmonary vessels to severe acute exacerbation of COPD (AE-COPD).

METHODS

This study enrolled 81 patients with COPD and 28 non-COPD subjects as control and assessed the percentage of CSA (%CSA) less than 5 mm(2) (%CSA<5) and %CSA in the range of 5-10 mm(2) (%CSA5-10) on high-resolution computed tomography images.

RESULTS

Compared with the non-COPD subjects, the COPD patients had lower %CSA<5. %CSA<5 was positively correlated with airflow limitation and negatively correlated with the extent of emphysema. COPD patients with lower %CSA<5 showed significantly increased incidences of severe AE-COPD (Gray's test; P=0.011). Furthermore, lower %CSA<5 was significantly associated with severe AE-COPD (hazard ratio, 2.668; 95% confidence interval, 1.225-5.636; P=0.010).

CONCLUSION

%CSA<5 was associated with an increased risk of severe AE-COPD. The distal pruning of the small pulmonary vessels is a part of the risk associated with AE-COPD, and %CSA<5 might be a surrogate marker for predicting AE-COPD.