MULTI-PHACET: multidimensional clinical phenotyping of hospitalised acute COPD exacerbations

Elevated blood lactate in COPD exacerbations associates with adverse clinical outcomes and signals excessive treatment with β2 -agonists

BACKGROUND AND OBJECTIVE

Raised blood lactate secondary to high dose β2 -agonist treatment has been reported in asthma exacerbations but has not been investigated during acute exacerbations of COPD (AECOPD). We explored associations of blood lactate measurements with disease outcomes and β2 -agonist treatments during AECOPD.

METHODS

Retrospective (n = 199) and prospective studies (n = 142) of patients hospitalized with AECOPD were conducted. The retrospective cohort was identified via medical records and the prospective cohort was recruited during hospitalization for AECOPD. Baseline demographics, comorbidities, β2 -agonist treatment, biochemical measurements and clinical outcomes were compared between patients with normal (≤2.0 mmol/L) versus elevated lactate (>2.0 mmol/L). Regression analyses examined associations of lactate measurements with β2 -agonist dosages.

RESULTS

Demographic data and comorbidities were similar between high versus normal lactate groups in both cohorts. The populations were elderly (mean >70 years), predominantly male (>60%) with reduced FEV1 (%) 48.2 ± 19 (prospective cohort). Lactate was elevated in approximately 50% of patients during AECOPD and not related to evidence of sepsis. In the prospective cohort, patients with high lactate had more tachypnoea, tachycardia, acidosis and hyperglycaemia (p < 0.05) and received more non-invasive ventilation (37% vs. 9.7%, p < 0.001, prospective cohort). There was a trend to longer hospitalization (6 vs. 5 days, p = 0.06, prospective cohort). Higher cumulative β2 -agonist dosages were linked to elevated lactate levels (OR 1.04, p = 0.01).

CONCLUSION

Elevated lactate during AECOPD was common, unrelated to sepsis and correlated with high cumulative doses of β2 -agonists. Raised lactate may indicate excessive β2 -agonist treatment and should now be investigated as a possible biomarker.

Physical Activity Profiles among Patients Admitted with Acute Exacerbations of Chronic Obstructive Pulmonary Disease

People with hospitalised acute exacerbations of chronic obstructive pulmonary disease (AECOPD) exhibit low levels of physical activity (PA) and increased risks of future exacerbations. While methods to objectively measure and express PA are established for people with stable COPD, less clarity exists for people during AECOPD. Further, the relationship between PA during AECOPD and clinically relevant outcomes remains uncertain. The purpose of the study was to evaluate how much PA (step count and intensity) people accumulate during hospitalised AECOPDs, and the effect of accumulated inpatient PA (expressed via differing metrics) on length of stay (LOS), PA recovery, and readmission risk. This study was a secondary analysis of prospective observational cohort data collected with Actigraph wActiSleep-BT devices from patients with AECOPD in a Melbourne hospital from 2016 to 2018. Step counts and PA intensity throughout the hospital admission and at one-month follow-up were collected and analysed. Sixty-eight participants were recruited for inpatient measurement, and 51 were retained for follow-up. There were no significant changes in step count or intensity across the inpatient days, but 33/51 (65%) of participants demonstrated a clinically meaningful improvement in steps per day from 3817.0 to 6173.7 at follow-up. Participants spent most time sedentary and in light PA, with both PA metrics demonstrating significant influences on LOS and follow-up PA intensity, but with generally low explanatory power (R2 value range 7-22%). Those who had LOS < 5 days spent significantly less time sedentary and more time in light PA than those with LOS ≥ 5 days (p < 0.001 for both). Time spent sedentary or in light PA appears to be the most promising metric to associate with clinically relevant outcomes related to recovery following AECOPD. These findings can inform future clinical practice for the evaluation of inpatient PA to better establish its role in the clinical management of patients with AECOPD.

Impact of Acute Exacerbation and Its Phenotypes on the Clinical Outcomes of Chronic Obstructive Pulmonary Disease in Hospitalized Patients: A Cross-Sectional Study

Acute exacerbations of COPD (AECOPD) are clinically significant events having therapeutic and prognostic consequences. However, there is a lot of variation in its clinical manifestations described by phenotypes. The phenotypes of AECOPD were categorized in this study based on pathology and exposure. In our cross-sectional study, conducted between 1 January 2016 to 31 December 2020, the patients were categorized into six groups based on pathology: non-bacterial and non-eosinophilic; bacterial; eosinophilic; bacterial infection with eosinophilia; pneumonia; and bronchiectasis. Further, four groups were classified based on exposure to tobacco smoke (TS), biomass smoke (BMS), both, or no exposure. Cox proportional-hazards regression analyses were performed to assess hazard ratios, and Kaplan-Meier analysis was performed to assess survival, which was then compared using the log-rank test. The odds ratio (OR) and independent predictors of ward admission type and length of hospital stay were assessed using binomial logistic regression analyses. Of the 2236 subjects, 2194 were selected. The median age of the cohort was 67.0 (60.0 to 74.0) and 75.2% were males. Mortality rates were higher in females than in males (6.2% vs. 2.3%). AECOPD-B (bacterial infection) subjects [HR 95% CI 6.42 (3.06-13.46)], followed by AECOPD-P (pneumonia) subjects [HR (95% CI: 4.33 (2.01-9.30)], were at higher mortality risk and had a more extended hospital stay (6.0 (4.0 to 9.5) days; 6.0 (4.0 to 10.0). Subjects with TS and BMS-AECOPD [HR 95% CI 7.24 (1.53-34.29)], followed by BMS-AECOPD [HR 95% CI 5.28 (2.46-11.35)], had higher mortality risk. Different phenotypes have different impacts on AECOPD clinical outcomes. A better understanding of AECOPD phenotypes could contribute to developing an algorithm for the precise management of different phenotypes.

Remote Monitoring for Prediction and Management of Acute Exacerbations in Chronic Obstructive Pulmonary Disease (AECOPD)

The progression of chronic obstructive pulmonary disease (COPD) is characterized by episodes of acute exacerbation (AECOPD) of symptoms, decline in respiratory function, and reduction in quality-of-life increasing morbi-mortality and often requiring hospitalization. Exacerbations can be triggered by environmental exposures, changes in lifestyle, and/or physiological and psychological factors to greater or lesser extents depending on the individual’s COPD phenotype. The prediction and early detection of an exacerbation might allow patients and physicians to better manage the acute phase. We summarize the recent scientific data on remote telemonitoring (TM) for the prediction and management of acute exacerbations in COPD patients. We discuss the components of remote monitoring platforms, including the integration of environmental monitoring data; patient reported outcomes collected via interactive Smartphone apps, with data from wearable devices that monitor physical activity, heart rate, etc.; and data from medical devices such as connected non-invasive ventilators. We consider how telemonitoring and the deluge of data it potentially generates could be combined with electronic health records to provide personalized care and multi-disease management for COPD patients.

The use of treatable traits to address COPD complexity and heterogeneity and to inform the care

COPD is complex and heterogeneous with respect to its aetiology, clinical presentation, phenotypes and biological mechanisms. Despite this, COPD is still diagnosed and treated according to simple clinical measures, including airflow limitation, symptoms and exacerbation frequency, leading to failure to recognise the disease's heterogeneity and/or to provide targeted interventions. COPD continues to have a very large burden of disease with suboptimal outcomes for people with the disease, including frequent hospitalisation with exacerbations, rapid lung function decline, multimorbidity and death from respiratory failure. In light of this, there have been increasing calls for a renewed taxonomy with better characterisation of COPD phenotypes and endotypes. This would allow the unravelling of COPD's complexity and heterogeneity, the implementation of targeted interventions and improved patient outcomes. The treatable traits strategy is a proposed vehicle for the implementation of precision medicine in chronic airway diseases. In this review, in addition to summarising the key knowledge on the heterogeneity of COPD, we refer to the existing evidence pertaining to the treatable traits strategy as applied in COPD and discuss implementation in different settings.

COPD is a heterogeneous clinical syndrome, which requires deconstruction of its individual components to facilitate targeted treatment and improve individual patient outcomes. 
https://bit.ly/2YXWgHN

Phenotyping acute exacerbation of COPD: what more can we do for hospitalised patients?

Hospitalised #AECOPD are characterised by multiple facets of aetiology. The clinical interpretation of the composite phenotypes of AECOPD and the robustness of the AECOPD phenotype need to be discussed further. https://bit.ly/3grzQEO.