Clinical Features according to the Frequency of Acute Exacerbation in COPD

Machine learning approaches for practical predicting outpatient near-future AECOPD based on nationwide electronic medical records

In this research, we aimed to harness machine learning to predict the imminent risk of acute exacerbation in chronic obstructive pulmonary disease (AECOPD) patients. Utilizing retrospective data from electronic medical records of two Taiwanese hospitals, we identified 26 critical features. To predict 3- and 6-month AECOPD occurrences, we deployed five distinct machine learning algorithms alongside ensemble learning. The 3-month risk prediction was best realized by the XGBoost model, achieving an AUC of 0.795, whereas the XGBoost was superior for the 6-month prediction with an AUC of 0.813. We conducted an explainability analysis and found that the episode of AECOPD, mMRC score, CAT score, respiratory rate, and the use of inhaled corticosteroids were the most impactful features. Notably, our approach surpassed predictions that relied solely on CAT or mMRC scores. Accordingly, we designed an interactive prediction system that provides physicians with a practical tool to predict near-term AECOPD risk in outpatients.

Plasma sCD146 is a potential biomarker for acute exacerbation of chronic obstructive pulmonary disease

This study examined the levels of soluble CD146 (sCD146) in plasma samples from patients with chronic obstructive pulmonary disease (COPD) and assessed the relationship between sCD146 and the severity of COPD. A total of 97 COPD patients were recruited from 20 medical centers in Jiangsu, China, including 13 stable subjects and 84 exacerbated subjects. The plasma sCD146 level in exacerbated subjects (28.77 ± 10.80 ng/mL) was significantly lower than that in stable subjects (38.84 ± 15.00 ng/mL). In the high sCD146 group, the proportion of subjects with modified Medical Research Council (mMRC) scores of 0-1 was higher, the proportion of subjects with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage 4 was lower, and the proportion of subjects with ≥1 hospitalizations in the past year was lower. The plasma sCD146 level was negatively correlated with the COPD Assessment Test (CAT) score (r = -0.2664, p = 0.0087). Logistic regression analysis showed that sCD146 was an independent risk factor for acute exacerbation of COPD (AECOPD). Receiver operating characteristic (ROC) analysis suggested that sCD146 combined with sex, age, pulmonary function, and acute exacerbations in the past year had clinical value for the accurate identification of AECOPD, with an area under the ROC curve (AUC) of 0.908 (95% CI: 0.810-1.000, p < 0.001). In addition, there was a significant negative correlation between plasma sCD146 and S100A9 (r = -0.3939, p < 0.001).

Clinical and pulmonary functions profiling of patients with chronic obstructive pulmonary disease experiencing frequent acute exacerbations

Purpose:

The present study aimed at clinical and pulmonary functions profiling of patients with chronic obstructive pulmonary disease (COPD) to anticipate future exacerbations.

Methods:

The study included 80 COPD patients; 40 patients had ≥2 acute exacerbations during preceding 1 year (frequent exacerbation [FECOPD] group) and 40 patients had <2 acute exacerbations during preceding 1 year (infrequent exacerbation [I-FECOPD] group). Clinical profile, sputum microbiology, blood gas analysis, spirometric indices, and diffusion capacity (transfer test) variables were assessed. Groups’ comparison was performed using an independent t-test for numeric scale parameters and Chi-square test for nominal parameters. Pearson's and Spearman's correlation coefficients were derived for numeric scale parameters and numeric nominal parameters, respectively. Multinomial logistic regression analysis was done using SPSS software.

Results:

FECOPD group contained younger patients than in I-FECOPD group although the difference was not statistically significant. There was no significant difference between two groups regarding smoking pack-years and duration of illness. FECOPD group had significantly more expectoration score and Modified Medical Research Council dyspnea scores. Cough score and wheeze score did not differ significantly between two groups. More patients in FECOPD group (12/40 vs. 4/40) had lower airway bacterial colonization. Arterial blood gas parameters were more deranged in FECOPD group. Spirometric indices (forced expiratory volume during 1^st s) as well as transfer test (both diffusing capacity for carbon monoxide and transfer coefficient of the lung values) were significantly reduced in FECOPD group.

Conclusions:

The patients in FECOPD group had clinical, spirometric, and transfer test profiling suggestive of a severe COPD phenotype, the recognition will help in predicting future exacerbations and a better management.

Serum CCL-18 level is a risk factor for COPD exacerbations requiring hospitalization

Introduction

Chemokine (C-C motif) ligand 18 (CCL-18) has been shown to be elevated in chronic obstructive pulmonary disease (COPD) patients. This study primarily aimed to evaluate whether the serum CCL-18 level differentiates the frequent exacerbator COPD phenotype from infrequent exacerbators. The secondary aim was to investigate whether serum CCL-18 level is a risk factor for exacerbations requiring hospitalization.

Materials and methods

Clinically stable COPD patients and participants with smoking history but normal spirometry (NSp) were recruited for the study. Modified Medical Research Council Dyspnea Scale, COPD Assessment Test, spirometry, and 6-min walking test were performed. Serum CCL-18 levels were measured with a commercial ELISA Kit.

Results

Sixty COPD patients and 20 NSp patients were recruited. Serum CCL-18 levels were higher in COPD patients than those in NSp patients (169 vs 94 ng/mL, P<0.0001). CCL-18 level was significantly correlated with the number of exacerbations (r=0.30, P=0.026), although a difference in CCL-18 values between infrequent and frequent exacerbator COPD (168 vs 196 ng/mL) subgroups did not achieve statistical significance (P=0.09). Serum CCL-18 levels were significantly higher in COPD patients who had experienced at least one exacerbation during the previous 12 months. Overall, ROC analysis revealed that a serum CCL-18 level of 181.71 ng/mL could differentiate COPD patients with hospitalized exacerbations from those who were not hospitalized with a 88% sensitivity and 88.2% specificity (area under curve: 0.92). Serum CCL-18 level had a strong correlation with the frequency of exacerbations requiring hospitalization (r=0.68, P<0.0001) and was found to be an independent risk factor for hospitalized exacerbations in the multivariable analysis.

Conclusion

CCL-18 is a promising biomarker in COPD, as it is associated with frequency of exacerbations, particularly with severe COPD exacerbations requiring hospitalization, as well as with functional parameters and symptom scores.

Diagnosis, assessment, and phenotyping of COPD: beyond FEV₁

COPD is now widely recognized as a complex heterogeneous syndrome, having both pulmonary and extrapulmonary features. In clinical practice, the diagnosis of COPD is based on the presence of chronic airflow limitation, as assessed by post-bronchodilator spirometry. The severity of the airflow limitation, as measured by percent predicted FEV1, provides important information to the physician to enable optimization of management. However, in order to accurately assess the complexity of COPD, there need to be other measures made beyond FEV1. At present, there is a lack of reliable and simple blood biomarkers to confirm and further assess the diagnosis of COPD. However, it is possible to identify patients who display different phenotypic characteristics of COPD that relate to clinically relevant outcomes. Currently, validated phenotypes of COPD include alpha-1 antitrypsin deficiency, and "frequent exacerbators". Recently, a definition and assessment of a new phenotype comprising patients with overlapping features of asthma and COPD has been suggested and is known as "asthma COPD overlap syndrome". Several other phenotypes have been proposed, but require validation against clinical outcomes. Defining phenotypes requires the assessment of multiple factors indicating disease severity, its impact, and its activity. Recognition and validation of COPD phenotypes has an important role to play in the selection of evidence-based targeted therapy in the future management of COPD, but regardless of the diagnostic terms, patients with COPD should be assessed and treated according to their individual treatable characteristics.

Persistent endothelial dysfunction turns the frequent exacerbator COPD from respiratory disorder into a progressive pulmonary and systemic vascular disease

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death in developed countries of the world, while the main cause of mortality and morbidity in COPD patients are acute exacerbations and cardiovascular diseases. With regard to the frequency of exacerbations the phenotype "frequent exacerbators" has been defined, which, besides a more severe clinical course and a significantly higher total mortality, is also characterised by an elevated risk of cardiovascular mortality, as some indicators show us. It is notable that during the exacerbation of COPD, next to other changes, a significant aggravation of endothelial function occurs while the ED and COPD relationship seems very complex and is still in greater part unknown. Making the pathophysiological link between the frequency of exacerbations of COPD and ED could change our understanding of the character of this type of pulmonary disease. We hypothesize that frequent exacerbator COPD is a progressive and generalised vascular disease, not only an isolated respiratory disorder with ancillary systemic effects. Our opinion is that differences in COPD phenotype do not only determine the clinical picture but could also be of key importance in defining the progressivity of the disease. ED, which in these patients persists between frequent exacerbations, could be the main cause of the progression of pulmonary disease, and not only of the high cardiovascular risk of these patients. Such a persistent ED in FE COPD, with its pro-inflammatory, vasoconstrictory and prothrombotic mechanisms, could contemporaneously induce new exacerbations of COPD, the progression of pulmonary changes and the development of systemic atherosclerosis as a main extrapulmonary manifestation in these patients. Such a model defines endothelium as a common soil of progressive pulmonary and cardiovascular changes in FE COPD. It can fully explain all the elements of the clinical course and co-morbidity in FE COPD, for which we still do not have adequate explanation.

Personalizing and targeting therapy for COPD: the role of molecular and clinical biomarkers

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characterized by persistent airflow limitation. It is the third leading cause of death worldwide, and there are currently no curative strategies for this disease. Many factors contribute to COPD susceptibility, progression and exacerbations. These include cigarette smoking, environmental and occupational pollutants, respiratory infections and comorbidities. As the clinical phenotypes of COPD are so variable, it has been difficult to devise an individualized treatment plan for patients with this complex chronic disease. This review will highlight how potential clinical, inflammatory, genomic and epigenomic biomarkers for COPD could be used to personalize treatment, leading to improved disease management and prevention for our patients.