ERS 2022: Exacerbations in COPD: Biomarkers and Management
This session has discussed various abstracts on the biomarkers of COPD exacerbations, their management, and the effect of COVID-19 among COPD patients.
Sputum is a mucus solution containing biological material that grows in volume and purulence during an acute COPD exacerbation (AECOPD). Sputum rheology was evaluated during stable state and AECOPD. The non-linear property yield strain ?c decreased from a stable state to AECOPD and increased 21 days after an exacerbation (AECOPD-fu). In addition, a negative association was observed between sputum rheology and FEV1 and BMI during stable COPD but not during AECOPD.
The forced oscillation technique (FOT) is a sensitive method for the early detection of obstructive disease, but its role in monitoring COPD is less established. Therefore, the study's objective was to investigate the value of FOT in stable COPD disease about future exacerbations. The study concluded that reactance at 5 Hz, particularly the difference between inspiratory and expiratory reactance, appears to be beneficial in predicting future exacerbations in COPD.
Although GOLD guidelines support using blood eosinophil counts (BEC) to guide inhaled corticosteroid (ICS) treatment in COPD, they do not require sampling during clinical stability. During an acute illness, BEC may fall. Admission BEC <0.05 is a strong negative prognostic index in severe COPD exacerbations. Results of the study demonstrated that BEC during hospitalisation for COPD exacerbation are not a reliable predictor of stable-stable eosinophil phenotype and should not be used to guide ICS therapy. However, historical BEC performs well at the 0.1 threshold, allowing for timely therapy optimisation within a high-risk period.
Because of the Covid-19 pandemic, measures such as social distance, self-protection, and lockdown can impact exacerbations in patients with COPD. A retrospective observational study aimed to evaluate these measures' impact on COPD patients' exacerbations. There was a decrease in the mean number of exacerbations during the lockdown period between March and May 2020 compared to the same period the previous year. The study's results suggest that measures like lockdown, social distance, and self-protection impact exacerbations in patients with COPD.
Patients with COPD show stability periods and acute exacerbations. Therefore, the study aimed to profile the plasma proteins associated with COPD at clinical stability or during exacerbations. In COPD, pathway functional and protein-protein network analyses of differentially abundant proteins showed dysregulations of inflammatory responses involving innate and antibody-mediated immunity, the complement system, and coagulation cascades. During clinical stability, systemic inflammation and a deficient humoral immune system persisted, primarily in the stable frequent exacerbation group.
In patients with cardiovascular disease, hyperhomocysteinemia is an independent thrombotic risk factor with several procoagulant action mechanisms. Smoking, inflammation, and oxidative stress are predictors of the development of hyperhomocysteinemia and COPD. In addition, homocysteine is a candidate for the main predictor of thrombophilia in COPD. Therefore, strategies to control hyperhomocysteinemia should be developed to prevent thrombophilia in COPD patients.
Acute exacerbations of COPD (AECOPD) are associated with increased utilisation of healthcare resources (HCRU) and mortality. A single, simple-to-understand visualisation model would facilitate the assessment of the evolution of these patients over time. The results of the COHERENT-COPD study concluded that in patients with AECOPD initially assisted in the emergency department; there was a high rate of readmissions (41.8%) and mortality (23.5%) at one year.
Viral and bacterial respiratory infections can cause AECOPD leading to various AECOPD phenotypes that impede prompt and effective treatment. FeNO is a non-invasive biomarker for the early etiologic diagnosis of AECOPD. Therefore, stabilising FeNO variability in COPD patients may be a putative target for individualised treatment that can reduce AECOPD and improve disease control.
Patients with COPD are at risk of severe COPID-19 illness; however, there is limited data on the burden of COVID-19 in this patient population. In COPD patients, the incidence of COVID-19 peaked in April 2020. Incidence rates of COVID-19 hospitalisation were significantly higher in patients with more severe COPD and highest in GOLD D group patients.
Genome-wide association studies independently demonstrated the association of rs 16969968 on the a5 subunit of a nicotinic receptor with nicotine addiction, cancer, and chronic obstructive pulmonary disease. However, no biological data is available on humans. Therefore, the role of rs 16969968 in the context of COPD was investigated. The study's results highlighted the role of SNPa5 in remodelling bronchial and bronchiolar epithelium, affecting the basal cells, primary cilia, and the secretion of Muc5ac in COPD patients.
AECOPD are a risk factor for mortality. Congestive heart failure (CHF) is one of the most frequent comorbidities. Patients with AECOPD have high one-year mortality and are greatly influenced by age and CHF.
Currently, respiratory pattern analysis is limited to simple biomarkers such as rate. However, respiratory waveforms are complex and typically sampled with high fidelity. Symmetric Projection Attractor Reconstruction (SPAR) provided additional, early evidence of patients who re-exacerbated. It was predicted that a combination of SPAR and conventional measures might support clinical decision-making during hospital discharge and community monitoring, providing patients, caregivers, and clinical teams with an earlier warning.
Machine Learning (ML) is increasingly being used to analyse clinical data. Clinical measurements obtained during telehealth care are an ideal raw material for ML because they represent patients' health status over long periods. The approaches presented in the study support the claim that ML aids in discovering patterns and predicting outcomes. It is possible to build ML models that can learn the patterns of AECOPD progression and make reliable predictions based on telehealthcare data.
A growing body of evidence suggests that lung microbiota plays a vital role in COPD. The study's objective was to observe diversity, composition, and microbial patterns in COPD sputum samples clustered by the GOLD stage. GOLD B and D (symptomatic patients) were associated with a significant decrease in richness and increased abundance of taxa as defined by alfa and beta diversity, respectively. Furthermore, the Linear discriminant analysis (LDA) score showed differences in bacterial composition between GOLD 1-3 and GOLD 4, with a repeated pattern of Haemophilus genus dominance in GOLD 4 patients.
Abnormalities of autonomic function have been reported in patients with COPD. Heart rate recovery at 1 min (HRR1) following completion of the Cardiopulmonary exercise test (CPET) is an independent predictor factor for AECOPD. The ROC analysis indicated that patients with HRR1 of less than 14 beats were more likely to suffer an exacerbation during the follow-up period.
AECOPD negatively impacts patients' health status, causes disease progression, and is the major driver of COPD-related health expenditure. In addition, poor medication adherence, GERD, depression, and serum albumin were associated with acute exacerbations of COPD. Therefore, strategies to optimise inhaled medication adherence, correction of GERD, depression and serum albumin can contribute to the prevention of AECOPD.
A study revealed that neutrophil-lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) are promising markers for predicting COPD severity and future acute exacerbation.
Pulmonary hypertension (PH) frequently complicates the course of COPD. It significantly impacts prognosis and, therefore, should be detected. A study showed that COPD-PH patients had higher rates of an extended stay in the hospital and a higher risk of exacerbation within 30 days compared to COPD alone. Therefore, echocardiography should be considered when evaluating patients with clinically significant COPD, given cardiac comorbidity's prognostic and therapeutic implications.
The majority of COPD patients are older adults with comorbidities. The most effective treatment for them
was the stabilisation of comorbidities and conventional oxygen, and for the most severe Helmet-CPAP and NIV. Furthermore, COPD patients had no higher risk of death from COVID-19 than individuals without a prior diagnosis of COPD.
In stable COPD, blood eosinophil count is a marker of steroid responsiveness. After treatment, patients with eosinophilic AECOPD have lower systemic inflammatory marker levels and improved airflow limitation. The surrogate markers to detect airway eosinophilia are not of equal value.
European Respiratory Society (ERS) International Congress 2022, 3rd-6th Sept. 2022, Barcelona
