Plasma C-reactive protein and endothelin-1 level in patients with chronic obstructive pulmonary disease and pulmonary hypertension

Neutrophil-to-lymphocyte ratio predicts poor prognosis in patients with chronic kidney disease-related pulmonary hypertension: A retrospective study

Inflammation plays a crucial role in chronic kidney disease (CKD) and pulmonary hypertension (PH). Considering that the neutrophil-to-lymphocyte ratio (NLR) has recently emerged as a powerful predictor of adverse outcomes in many chronic diseases, we aimed to investigate the association between NLR and all-cause mortality in patients with CKD-related PH. A total of 176 hospitalized patients with predialysis CKD-related PH were recruited retrospectively from January 2012 to June 2020 by reviewing electronic medical records. The NLR and clinical characteristics of the patients were included in the current analysis. The Kaplan-Meier method and univariate and multivariate Cox regression analyses were performed to identify the association between NLR and the incidence of all-cause mortality. Baseline NLR values were associated with hemoglobin, estimated glomerular filtration rate and C-reactive protein. During a median follow-up period of 32.5 (11.3-53.0) months, 23 patients died. Regardless of whether the NLR acted as a continuous variable with a hazard ratio of 1.408 (95% confidence interval: 1.124-1.763) or a categorical variable (NLR ≤4.3 vs NLR >4.3) with a hazard ratio of 3.100 (95% confidence interval: 1.299-7.402), an elevated NLR was significantly associated with all-cause mortality in different models. A greater NLR at baseline was remarkably associated with a higher all-cause mortality in hospitalized patients with CKD-related PH.

WISP1 and Macrophage Migration Inhibitory Factor in Respiratory Inflammation: Novel Insights and Therapeutic Potentials for Asthma and COPD

Recent advancements highlight the intricate interplay between the extracellular matrix (ECM) and immune responses, notably in respiratory diseases such as asthma and Chronic Obstructive Pulmonary Disease (COPD). The ECM, a dynamic structural framework within tissues, orches-trates a plethora of cellular processes, including immune cell behavior and tissue repair mecha-nisms. WNT1-inducible-signaling pathway protein 1 (WISP1), a key ECM regulator, controls immune cell behavior, cytokine production, and tissue repair by modulating integrins, PI3K, Akt, β-catenin, and mTOR signaling pathways. WISP1 also induces macrophage migration inhibitory factor (MIF) expression via Src kinases and epidermal growth factor receptor (EGFR) activation. MIF, through its wide range of activities, enhances inflammation and tissue restructuring. Rec-ognized for its versatile roles in regulating the immune system, MIF interacts with multiple immune components, such as the NLRP3 inflammasome, thereby sustaining inflammatory pro-cesses. The WISP1-MIF axis potentially unveils complex molecular mechanisms governing im-mune responses and inflammation. Understanding the intricate roles of WISP1 and MIF in the pathogenesis of chronic respiratory diseases such as asthma and COPD could lead to the identi-fication of novel targets for therapeutic intervention to alleviate disease severity and enhance patient outcomes.

Clinical characteristics and predictors of pulmonary hypertension in chronic obstructive pulmonary disease at different altitudes

BACKGROUND

Pulmonary hypertension (PH) is a common complication in patients with chronic obstructive pulmonary disease (COPD) and is closely associated with poor prognosis. However, studies on the predictors of PH in COPD patients are limited, especially in populations living at high altitude (HA).

OBJECTIVES

To investigate the differences in the clinical characteristics and predictors of patients with COPD/COPD and PH (COPD-PH) from low altitude (LA, 600 m) and HA (2200 m).

METHODS

We performed a cross-sectional survey of 228 COPD patients of Han nationality admitted to the respiratory department of Qinghai People's Hospital (N = 113) and West China Hospital of Sichuan University (N = 115) between March 2019 and June 2021. PH was defined as a pulmonary arterial systolic pressure (PASP) > 36 mmHg measured using transthoracic echocardiography (TTE).

RESULTS

The proportion of PH in COPD patients living at HA was higher than that in patients living at LA (60.2% vs. 31.3%). COPD-PH patients from HA showed significantly different in baseline characteristics, laboratory tests and pulmonary function test. Multivariate logistic regression analysis indicated that the predictors of PH in COPD patients were different between the HA and LA groups.

CONCLUSIONS

The COPD patients living at HA had a higher proportion of PH than those living at LA. At LA, increased B-type natriuretic peptide (BNP) and direct bilirubin (DB) were predictors for PH in COPD patients. However, at HA, increased DB was a predictor of PH in COPD patients.

The Incidence and Prevalence of Pulmonary Hypertension in the COPD Population: A Systematic Review and Meta-Analysis

Purpose

Chronic obstructive pulmonary disease (COPD)-related pulmonary hypertension (PH) is one of the most common comorbidities of COPD, and often leads to a worse prognosis. Although the estimated prevalence and risk factors of COPD-related PH have been widely reported, these results have not been well integrated. This study aimed to review the worldwide incidence and prevalence of COPD-related PH and explore possible factors affecting its prevalence.

Patients and Methods

We searched four electronic databases (Web of Science, Embase, Cochrane, and MEDLINE) to identify all observational studies on the prevalence of COPD-related PH from database creation until July 20, 2021. Eligibility screening, quality assessment, and data extraction of the retrieved studies were independently conducted by two reviewers. Meta-analyses were performed to determine the prevalence of PH in the COPD population. Random-effects meta-regression model analyses were conducted to investigate the sources of heterogeneity.

Results

Altogether, 38 articles were included in the meta-analyses. The pooled prevalence was 39.2% (95% CI: 34.0–44.4, I² = 97.6%) for COPD-related PH. Subgroup analyses showed that the prevalence of PH increased with COPD severity, where the majority (30.2%) had mild PH and the minority had severe PH (7.2%). Furthermore, we found a significant regional difference in the prevalence of COPD-related PH (P = 0.000), which was the highest in Africa (64.0%) and the lowest in Europe (30.4%). However, stratified studies on other factors involving mean age, sex, enrolment time, participant recruitment settings, and PH diagnostic methods showed no significant differences in prevalence (P >0.05).

Conclusion

The global incidence of PH in the COPD population is very high, and there are significant regional and international variations. Patients with COPD should be screened for PH and contributing risk factors to reduce the burden on individuals and society.

Retinal Vascular Changes in Patients with Chronic Obstructive Pulmonary Disease: An Optical Coherence Tomography Angiography Study

Objectives:

In the current study, we aimed to investigate retinal vascular density and blood flow changes in patients with chronic obstructive pulmonary disease (COPD) using optical coherence tomography angiography (OCTA) (AngioVue Avanti, Optovue).

Methods:

Thirty eyes of 30 patients with COPD and 30 eyes of 30 healthy controls were evaluated with OCTA. Foveal and parafoveal vessel density, inner retinal and choriocapillary flow area, and foveal avascular zone (FAZ) area were measured and compared between the groups.

Results:

No statistically significant differences were observed in the outer retinal flow area and choriocapillary flow area measurements between the groups (p=0.609 and p=0.162, respectively). There was no statistically significant difference in FAZ and FAZ perimeter values between the groups (p=0.725 and p=0.820, respectively). Vascular density measurements in the superficial foveal and parafoveal areas were not statistically significantly different between the groups (p>0.05, for all). Deep parafoveal vascular density values of the COPD group were statistically significantly lower than the control group in all investigated areas except the superior and inferior quadrants.

Conclusion:

The results of our study demonstrated for the first time that vascular density decreased in the parafoveal area due to COPD-related hypoxemia and endothelial dysfunction.

Progress in the mechanism and targeted drug therapy for COPD

Chronic obstructive pulmonary disease (COPD) is emphysema and/or chronic bronchitis characterised by long-term breathing problems and poor airflow. The prevalence of COPD has increased over the last decade and the drugs most commonly used to treat it, such as glucocorticoids and bronchodilators, have significant therapeutic effects; however, they also cause side effects, including infection and immunosuppression. Here we reviewed the pathogenesis and progression of COPD and elaborated on the effects and mechanisms of newly developed molecular targeted COPD therapeutic drugs. Among these new drugs, we focussed on thioredoxin (Trx). Trx effectively prevents the progression of COPD by regulating redox status and protease/anti-protease balance, blocking the NF-κB and MAPK signalling pathways, suppressing the activation and migration of inflammatory cells and the production of cytokines, inhibiting the synthesis and the activation of adhesion factors and growth factors, and controlling the cAMP-PKA and PI3K/Akt signalling pathways. The mechanism by which Trx affects COPD is different from glucocorticoid-based mechanisms which regulate the inflammatory reaction in association with suppressing immune responses. In addition, Trx also improves the insensitivity of COPD to steroids by inhibiting the production and internalisation of macrophage migration inhibitory factor (MIF). Taken together, these findings suggest that Trx may be the ideal drug for treating COPD.

C-Reactive Protein and All-Cause Mortality in Patients with Stable Coronary Artery Disease: A Secondary Analysis Based on a Retrospective Cohort Study

Background

The association between C-reactive protein (CRP) and all-cause mortality (ACM) in patients with stable coronary artery disease (CAD) is unclear. Therefore, the aim of the present study was to explore the correlation between CRP and ACM in stable CAD patients.

Material/Methods

This study was a secondary analysis. Between October 2014 and October 2017, 196 patients aged 43 to 98 years who had a first diagnosis of stable CAD were recruited into this study. We divided the patients into 4 groups (Quartile 1: 0.01–0.03 mg/dL; Quartile 2: 0.04–0.11 mg/dL; Quartile 3: 0.12–0.33 mg/dL; and Quartile 4: 0.34–9.20 mg/dL) according to the concentration of CRP. The indicator surveyed in this research was ACM.

Results

During a median follow-up of 783 days, ACM occurred in 18 patients, with a mortality rate of 9.18% (18/196). Univariate analysis showed that elevated CRP was closely related to ACM in stable CAD patients (P<0.005). After controlling for potential confounding factors by multivariate logistic regression analysis, this relationship still existed. Pearson correlation analysis showed that elevated CRP log10 transform was associated with LVEF (r=−0.1936, P=0.0067). Receiver operating characteristic (ROC) curve analysis showed that the optimal concentration of CRP for the diagnosis of ACM was 0.345, and the area under the curve (AUC) was 0.735.

Conclusions

Elevated CRP is associated with ACM in stable CAD patients, and the best diagnostic threshold is 0.345.

Effectiveness of long-term using statins in COPD - a network meta-analysis

OBJECTIVES

To evaluate the effectiveness of long-term treatment of statins for chronic obstructive pulmonary disease (COPD), and to answer which one is better.

METHODS

General meta-analysis was performed to produce polled estimates of the effect of mortality, inflammatory factors, and lung function index in COPD patients by the search of PubMed, Web of Science, Embase, and China National Knowledge Infrastructure for eligible studies. A network meta-analysis was performed to synthetically compare the effectiveness of using different statins in COPD patients.

RESULTS

General meta-analysis showed that using statins reduced the risk of all-cause mortality, heart disease-related mortality and COPD acute exacerbation (AECOPD) in COPD patients, the RR (95% CI) were 0.72 (0.63,0.84), 0.72 (0.53,0.98) and 0.84 (0.79,0.89), respectively. And using statins reduced C-reactive protein (CRP) and pulmonary hypertension (PH) in COPD patients, the SMD (95% CI) were - 0.62 (- 0.52,-0.72) and - 0.71 (- 0.85,-0.57), respectively. Network meta-analysis showed that Fluvastatin (97.7%), Atorvastatin (68.0%) and Rosuvastatin (49.3%) had higher cumulative probability than other statins in reducing CRP in COPD patients. Fluvastatin (76.0%) and Atorvastatin (75.4%) had higher cumulative probability than other satins in reducing PH in COPD patients.

CONCLUSIONS

Using statins can reduce the risk of mortality, the level of CRP and PH in COPD patients. In addition, Fluvastatin and Atorvastatin are more effective in reducing CRP and PH in COPD patients.

Pulmonary hypertension associated with lung diseases and hypoxemia

Pulmonary hypertension that develops in the setting of underlying lung diseases such as COPD or idiopathic pulmonary fibrosis (IPF) is associated with decreased functional status, worsening hypoxemia and quality of life, and increased mortality. This complication of lung disease is complex in its origin and carries a unique set of diagnostic and therapeutic issues. This review attempts to provide an overview of mechanisms associated with the onset of pulmonary hypertension in COPD and IPF, touches on appropriate evaluation, and reviews the state of knowledge on treating pulmonary hypertension related to underlying lung disease.

Obesity and inflammation: the linking mechanism and the complications

Obesity is the accumulation of abnormal or excessive fat that may interfere with the maintenance of an optimal state of health. The excess of macronutrients in the adipose tissues stimulates them to release inflammatory mediators such as tumor necrosis factor α and interleukin 6, and reduces production of adiponectin, predisposing to a pro-inflammatory state and oxidative stress. The increased level of interleukin 6 stimulates the liver to synthesize and secrete C-reactive protein. As a risk factor, inflammation is an imbedded mechanism of developed cardiovascular diseases including coagulation, atherosclerosis, metabolic syndrome, insulin resistance, and diabetes mellitus. It is also associated with development of non-cardiovascular diseases such as psoriasis, depression, cancer, and renal diseases. On the other hand, a reduced level of adiponectin, a significant predictor of cardiovascular mortality, is associated with impaired fasting glucose, leading to type-2 diabetes development, metabolic abnormalities, coronary artery calcification, and stroke. Finally, managing obesity can help reduce the risks of cardiovascular diseases and poor outcome via inhibiting inflammatory mechanisms.

MicroRNA-27a/b mediates endothelin-1-induced PPARγ reduction and proliferation of pulmonary artery smooth muscle cells

The down-regulation of peroxisome proliferator-activated receptor γ (PPARγ) expression has been found to correlate with the proliferation of pulmonary artery smooth muscle cells (PASMC), pulmonary vascular remodeling and pulmonary hypertension, while the molecular mechanisms underlying PPARγ reduction in PASMC remain largely unclear. The aim of the current study is to address this issue. Endothelin-1 (ET-1) dose- and time-dependently resulted in PPARγ reduction and proliferation of primary cultured rat PASMC, which was accompanied by the activation of nuclear factor-kappaB (NF-κB) and subsequent induction of microRNA-27a/b (miR-27a/b) expression. Chromatin immunoprecipitation assay revealed that NF-κB directly bound to the promoter regions of miR-27a/b. Luciferase reporter assay identified that miR-27a/b directly regulates the expression of PPARγ in PASMC. Further study indicated that the presence of either NF-κB inhibitor pyrrolidinedithiocarbamate or prior silencing miR-27a/b with anti-miRNA oligonucleotides suppressed ET-1-induced PPARγ reduction and proliferation of PASMC, while overexpression of miR-27a/b reduced PPARγ expression and enhanced PASMC proliferation. Taken together, our study demonstrates that ET-1 stimulates miR-27a/b expression by activation of the NF-κB pathway, which in turn results in PPARγ reduction and contributes to ET-1-induced PASMC proliferation.

iTRAQ-Based Proteomics Reveals Novel Biomarkers for Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a gradual lung disease with a survival of less than 5 years post-diagnosis for most patients. Poor molecular description of IPF has led to unsatisfactory interpretation of the pathogenesis of this disease, resulting in the lack of successful treatments. The objective of this study was to discover novel noninvasive biomarkers for the diagnosis of IPF. We employed a coupled isobaric tag for relative and absolute quantitation (iTRAQ)-liquid chromatography–tandem mass spectrometry (LC–MS/MS) approach to examine protein expression in patients with IPF. A total of 97 differentially expressed proteins (38 upregulated proteins and 59 downregulated proteins) were identified in the serum of IPF patients. Using String software, a regulatory network containing 87 nodes and 244 edges was built, and the functional enrichment showed that differentially expressed proteins were predominantly involved in protein activation cascade, regulation of response to wounding and extracellular components. A set of three most significantly upregulated proteins (HBB, CRP and SERPINA1) and four most significantly downregulated proteins (APOA2, AHSG, KNG1 and AMBP) were selected for validation in an independent cohort of IPF and other lung diseases using ELISA test. The results confirmed the iTRAQ profiling results and AHSG, AMBP, CRP and KNG1 were found as specific IPF biomarkers. ROC analysis indicated the diagnosis potential of the validated biomarkers. The findings of this study will contribute in understanding the pathogenesis of IPF and facilitate the development of therapeutic targets.

Associations of big endothelin-1 and C-reactive protein in atrial fibrillation

Background

Atrial fibrillation (AF) is associated with inflammation and endothelial dysfunction. However, the association between inflammation (as indexed by high-sensitivity C-reactive protein, hs-CRP) and endothelial function [as indexed by big endothelin-1 (ET-1)] in AF patients remains unclear.

Methods

We enrolled 128 patients with lone AF, among which 83 had paroxysmal AF, and 45 had persistent AF. Eighty-two age- and gender-matched controls of paroxysmal supraventricular tachycardia without AF history were evaluated. Plasma hs-CRP, big ET-1 levels and other clinical characteristics were compared among the groups.

Results

Patients with persistent AF had higher hs-CRP concentrations than those with paroxysmal AF (P < 0.05), both groups had higher hs-CRP level than controls (P < 0.05). Patients with persistent AF had higher big ET-1 level than those with paroxysmal AF, although the difference did not reach the statistical significance (P > 0.05), and both groups had higher big ET-1 levels than controls (P < 0.05). Multiple regression analyses revealed hs-CRP as an independent determinant of AF (P < 0.001). Further adjusted for big ET-1, both big ET-1 and hs-CRP were independent predictors for AF (P < 0.001), but the odds ratio for hs-CRP in predicting AF attenuated from 8.043 to 3.241. There was a positive relation between hs-CRP level and big ET-1 level in paroxysmal AF patients (r = 0.563, P < 0.05), however, the relationship in persistent AF patients was poor (r = 0.094, P < 0.05).

Conclusions

Both plasma hs-CRP and big ET-1 levels are elevated in lone AF patients, and are associated with AF. In paroxysmal lone AF patients, there were significant positive correlations between plasma hs-CRP level and big ET-1 level.

COPD-associated pulmonary hypertension: clinical implications and current methods for treatment

INTRODUCTION

Chronic obstructive pulmonary disease is the fourth leading cause of death worldwide, one serious complication being pulmonary hypertension, which occurs in up to 30% of patients and increases mortality drastically. Difficulties in diagnosis and the unclear beneficial effects of PH-specific therapy have hitherto resulted in the absence of approved therapies. Consequently, PH and right heart failure in COPD are still currently treated according to symptoms and not underlying cause Areas covered: This review focuses on the current knowledge of its pathogenesis, clinical picture, diagnosis as well as methods for treatment Expert commentary: Since PH-COPD is an orphan disease with grievous consequences, and diagnosis as well as the right choice of possible treatment is crucial, referral to an expert center in cases of suspicion is necessary. Hitherto there is no officially approved treatment available even though several studies have shown notable improvement in selected individuals, making diagnostics, prognostic markers, and the search for therapeutic agents key issues of interest in this field.

Risk factors for pulmonary hypertension in patients receiving maintenance peritoneal dialysis

We investigated the risk factors for pulmonary hypertension (PH) in patients receiving maintenance peritoneal dialysis (MPD). A group of 180 end-stage renal disease patients (124 men and 56 women; mean age: 56.43±8.36) were enrolled in our study, which was conducted between January 2009 and June 2014. All of the patients received MPD treatment in the Dialysis Center of the Second Affiliated Hospital of Soochow University. Clinical data, laboratory indices, and echocardiographic data from these patients were collected, and follow-ups were scheduled bi-monthly. The incidence and relevant risk factors of PH were analyzed. The differences in measurement data were compared by t-test and enumeration data were compared with the χ2 test. Among the 180 patients receiving MPD, 60 were diagnosed with PH. The remaining 120 were regarded as the non-PH group. Significant differences were observed in the clinical data, laboratory indices, and echocardiographic data between the PH and non-PH patients (all P<0.05). Furthermore, hypertensive nephropathy patients on MPD showed a significantly higher incidence of PH compared with non-hypertensive nephropathy patients (P<0.05). Logistic regression analysis showed that the proportion of internal arteriovenous fistula, C-reactive protein levels, and ejection fraction were the highest risk factors for PH in patients receiving MPD. Our study shows that there is a high incidence of PH in patients receiving MPD and hypertensive nephropathy patients have an increased susceptibility to PH.

Prevalence and risk factors for pulmonary arterial hypertension in end-stage renal disease patients undergoing continuous ambulatory peritoneal dialysis

BACKGROUND

Pulmonary arterial hypertension (PAH) is a major complication in renal failure patients, but very little information is available on the cardiovascular parameters in these patients. The prevalence and risk factors for PAH were systematically evaluated in patients with end-stage renal diseases (ESRD) undergoing continuous ambulatory peritoneal dialysis (CAPD).

METHODS

Between January 2010 and January 2014, 177 ESRD patients (85 males and 92 females) undergoing CAPD therapy were recruited. General data, biochemical parameters and echocardiographic findings were collected and PAH risk factors studied.

RESULTS

Study participants consisted of 65 patients (36.52%) with PAH (PAH group) and 112 patients without PAH (non-PAH group). The interdialytic weight gain, systolic blood pressure and diastolic blood pressure (DBP), mean arterial pressure and hypertensive nephropathy incidence in the PAH group were significantly higher than the non-PAH group (all p < 0.05). There were significant differences between PAH group and non-PAH group in C-reactive protein-positive rate, N-terminal pro-brain natriuretic peptide (NT-proBNP), hemoglobin, prealbumin and serum albumin levels (all p < 0.05). Compared with non-PAH group, PAH group showed significant increases in right ventricular internal diameter (RVID), right ventricular outflow tract diameter (RVOTD), main pulmonary artery diameter, left atrial diameter (LAD), left ventricular end-diastolic diameter, interventricular septal thickness, left ventricular mass index, early diastolic mitral annulus velocity and valve calcification incidence (all p < 0.05), and decreased left ventricular ejection fraction (LVEF), tricuspid annulus plane systolic excursion (TAPSE) and early diastolic blood flow peak and mitral annulus velocity (E/E') (all p < 0.05). Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E' are major risk factors for PAH.

CONCLUSION

We observed a high incidence of PAH in ESRD patients undergoing CAPD. Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E' are high-risk factors for PAH in ESRD patients undergoing CAPD.

Pulmonary Arterial Pressure Response During Exercise in COPD: A Correlation with C-Reactive Protein (hsCRP)

Background:

The non-invasive assessment of pulmonary haemodynamics during exercise provides complementary data for the evaluation of exercise tolerance in patients with COPD.

Methods:

Exercise echocardiography in the semi-supine position was performed in 27 patients with COPD (C) with a forced expiratory volume in one second (FEV1) of 36±12% predicted and 13 age and gender-matched non-COPD subjects (NC). COPD patients also underwent cardiopulmonary exercise testing with gas exchange detection (CPET). Furthermore, serum high sensitive C-reactive protein (hsCRP), a marker of systemic inflammation, was also measured.

Results:

The maximal work rate (WRmax) and aerobic capacity (VO2peak) were significantly reduced (WRmax: 77±33 Watt, VO2peak: 50±14 %pred) in COPD. Pulmonary arterial systolic pressure (PAPs) was higher in COPD versus controls both at rest (39±5 vs. 31±2 mmHg, p<0.001), and at peak exercise (72±12 vs. 52±8 mmHg, p<0.001). In 19 (70%) COPD patients, the increase in PAPs was above 22 mmHg. The change in pressure (dPAPs) correlated with hsCRP (r2=0.53, p<0.0001) and forced vital capacity (FVC) (r2=0.18, p<0.001).

Conclusion:

PAPs at rest and during exercise were significantly higher in COPD patients and correlated with higher hsCRP. This may indicate a role for systemic inflammation and hyperinflation in the pulmonary vasculature in COPD.

The study was registered at ClinicalTrials.gov webpage with NCT00949195 registration number.

Biomarkers for pediatric pulmonary arterial hypertension: challenges and recommendations

Pediatric pulmonary arterial hypertension (PAH) is an uncommon disease that can occur in neonates, infants, and children, and is associated with high morbidity and mortality. Despite advances in treatment strategies over the last two decades, the underlying structural and functional changes to the pulmonary arterial circulation are progressive and lead eventually to right heart failure. The management of PAH in children is complex due not only to the developmental aspects but also because most evidence-based practices derive from adult PAH studies. As such, the pediatric clinician would be greatly aided by specific characteristics (biomarkers) objectively measured in children with PAH to determine appropriate clinical management. This review highlights the current state of biomarkers in pediatric PAH and looks forward to potential biomarkers, and makes several recommendations for their use and interpretation.

Oxygen therapy for COPD

Chronic obstructive pulmonary disease (COPD) is a leading cause of disability and death globally, characterised by progressive breathlessness, loss of function and, in its later stages, chronic hypoxaemia. Long-term continuous oxygen therapy increases life expectancy in patients with severe resting hypoxaemia. However, there are few data to support the use of oxygen in patients with only mild hypoxaemia and more research is required to determine any benefits of oxygen supplementation in COPD in such individuals.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Pulmonary hypertension due to lung diseases and/or hypoxia

Chronic lung diseases are common causes of pulmonary hypertension. It ranks second after the left heart disease. Both obstructive and restrictive lung diseases are know to cause pulmonary hypertension.

The pathophysiology of the disease is complex, and includes factors affecting the blood vessels, airways, and lung parenchyma. Hypoxia and the inhalation of toxic materials are another contributing factors. Recent guidelines have further clarified the association between pulmonary hypertension and chronic lung disease and made general guidelines concerning the diagnosis and management.

In this article, we will provide a detailed revision about the new classification and give general recommendations about the management of pulmonary hypertension in chronic lung diseases.

Color Doppler Evaluation of the Retrobulbar Hemodynamic Changes in Chronic Obstructive Pulmonary Disease: COPD and Retrobulbar Hemodynamic Changes

The aim of this study was to evaluate the hemodynamic changes in the extraocular orbital vessels of the patients with chronic obstructive pulmonary disease (COPD), using color Doppler ultrasonography, and to compare the results with those of healthy control subjects. The control group consisted of 35 healthy subjects who had no systemic problems, while the study group consisted of 60 patients with the diagnosis of COPD. Patients with COPD were grouped according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD). Twenty patients of stage 1 COPD (mild airflow limitation), stage 2 COPD (moderate airflow limitation), or stage 3 COPD (severe airflow limitation) were included in the groups 1, 2, and 3, respectively. Measurements were performed in both eyes of each participant. Peak systolic velocity (PSV), end-diastolic velocity (EDV), resistance index (RI), and pulsatility index (PI) were measured in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery (PCA). The RI and PI measurements of the OA, CRA, and PCA were significantly higher in group 3 when compared to the control group and groups 1 and 2. These significances were not observed when PSV and EDV values were compared. There were also no significant differences between groups 1, 2, and control patients, when mean PSV, EDV, RI, and PI values of all arteries were compared. None of the above parameters showed statistical significance when mean RI, PI, PSV, and EDV were compared between left and right eyes. Severe (stage 3) COPD is associated with impaired retrobulbar hemodynamics. Increased hypoxia and vascular mediators may be suggested in etiology.

Adenosine A2B receptor and hyaluronan modulate pulmonary hypertension associated with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide. The development of pulmonary hypertension (PH) in patients with COPD is strongly associated with increased mortality. Chronic inflammation and changes to the lung extracellular matrix (ECM) have been implicated in the pathogenesis of COPD, yet the mechanisms that lead to PH secondary to COPD remain unknown. Our experiments using human lung tissue show increased expression levels of the adenosine A2B receptor (ADORA2B) and a heightened deposition of hyaluronan (HA; a component of the ECM) in remodeled vessels of patients with PH associated with COPD. We also demonstrate that the expression of HA synthase 2 correlates with mean pulmonary arterial pressures in patients with COPD, with and without a secondary diagnosis of PH. Using an animal model of airspace enlargement and PH, we show that the blockade of ADORA2B is able to attenuate the development of a PH phenotype that correlates with reduced levels of HA deposition in the vessels and the down-regulation of genes involved in the synthesis of HA.

Biomarkers for pediatric pulmonary arterial hypertension - a call to collaborate

Therapeutic approaches in pediatric pulmonary arterial hypertension (PAH) are based primarily on clinician experience, in contrast to the evidence-based approach in adults with pulmonary hypertension. There is a clear and present need for non-invasive and objective biomarkers to guide the accurate diagnosis, treatment, and prognosis of this disease in children. The multifaceted spectrum of disease, clinical presentation, and association with other diseases makes this a formidable challenge. However, as more progress is being made in the understanding and management of adult PAH, the potential to apply this knowledge to children has never been greater. This review explores the state of the art with regard to non-invasive biomarkers in PAH, with an eye toward those adult PAH biomarkers potentially suitable for application in pediatric PAH.

C-reactive protein levels are raised in stable Chronic obstructive pulmonary disease patients independent of smoking behavior and biomass exposure

BACKGROUND

The aim of this case control study is to assess the relationship between serum C-reactive protein (CRP) levels and well-known clinical parameters in Chronic obstructive pulmonary disease (COPD) considering the impact of smoking behavior, biomass exposure and accompanying clinical entities, namely pulmonary hypertension, systemic hypertension and diabetes mellitus.

METHODS

Spirometry, echocardiography, arterial oxygen saturation (SpO2) measurements, BODE scores and serum CRP levels were investigated in stable COPD patients. Associations between CRP levels and clinical parameters were evaluated.

RESULTS

CRP levels are significantly higher in COPD patients than in healthy controls. CRP levels were not significantly different between COPD patients treated with inhaled corticosteroids and those not treated. CRP levels significantly correlated with age, FEV1% predicted, FVC% predicted, SpO2, MMRC, 6 minute walk distance, BODE scores and haemoglobin levels. In multivariate analysis BODE scores and concomitant systemic hypertension manifested the strongest association with CRP levels. CRP levels in COPD patients with and without pulmonary hypertension were significantly different. CRP levels did not differ significantly according to smoking status or biomass exposure, moreover COPD cases due to biomass exposure who never smoked also had higher CRP levels compared to healthy controls.

CONCLUSIONS

Systemic inflammation is inherent to COPD independent of ever-smoking status and correlates with disease severity, concomitant systemic hypertension and pulmonary hypertension.

Pulmonary Hypertension Secondary to COPD

The development of pulmonary hypertension in COPD adversely affects survival and exercise capacity and is associated with an increased risk of severe acute exacerbations. Unfortunately not all patients with COPD who meet criteria for long term oxygen therapy benefit from it. Even in those who benefit from long term oxygen therapy, such therapy may reverse the elevated pulmonary artery pressure but cannot normalize it. Moreover, the recent discovery of the key roles of endothelial dysfunction and inflammation in the pathogenesis of PH provides the rationale for considering specific pulmonary vasodilators that also possess antiproliferative properties and statins.