Exacerbations and health care resource use among patients with COPD in relation to blood eosinophil counts

Extending the data collection from a clinical trial: The Extended Salford Lung Study research cohort

The Extended Salford Lung Study (Ext-SLS) is an extension of the Salford Lung Studies (SLS) in asthma and chronic obstructive pulmonary disease (COPD) through retrospective and prospective collection of patient-level electronic health record (EHR) data. We compared the Ext-SLS cohort with the SLS intention-to-treat populations using descriptive analyses to determine if the strengths (e.g. randomization) of the clinical trial were maintained in the new cohort. Historical and patient-reported outcome data were captured from asthma-/COPD-specific questionnaires (e.g., Asthma Control Test [ACT]/COPD Assessment Test [CAT]). The Ext-SLS included 1147 participants (n = 798, SLS asthma; n = 349, SLS COPD). Of participants answering the ACT, 39% scored <20, suggesting poorly controlled asthma. For COPD, 61% of participants answering the CAT scored ≥21, demonstrating a high disease burden. Demographic/clinical characteristics of the cohorts were similar at SLS baseline. EHR data provided a long-term view of participants' disease, and questionnaires provided information not typically captured. The Ext-SLS cohort is a valuable resource for respiratory research, and ongoing prospective data collection will add further value and ensure the Ext-SLS is an important source of patient-level information on obstructive airways disease.

Clinical features and three-year prognosis of AECOPD patients with different levels of blood eosinophils

BACKGROUND

Eosinophils are thought to be associated with the frequency and severity of acute exacerbations of chronic obstructive pulmonary disease (AECOPD); however, the role of eosinophilic inflammation in AECOPD is still incompletely understood.

OBJECTIVES

To investigate the relationship between different levels of blood eosinophils and clinical features, including comorbidities, therapy, and prognosis, and to further explore the optimal eosinophilic cutoff.

METHODS

We retrospectively collected and analyzed medical data, laboratory findings, chest CT images, treatment, and three-year follow-up data from 984 AECOPD patients with different blood eosinophil (EOS) levels: EOS%<2%, ≥2%; EOS%<3%, ≥3%; eosinophil counts<100 cells/L, ≥100 cells/L.

RESULTS

The prevalence of eosinophilia was 36.48% of EOS≥2% (359 cases), 22.87% of EOS≥3% (225 cases), and 48.48% with eosinophil counts≥100 cells/µl (477 cases). EOS was associated with comorbidities, including pulmonary heart disease, arrhythmia (atrial fibrillation), laboratory testing and clinical treatment, including respiratory failure, airway limitation, infectious inflammation, rate of antibiotic use, systemic glucocorticoids, and three mortality rates. The ROC curve showed that the indicators of AUC≥0.5 included chest CT imaging (emphysema 1.8% or ≥100/µl, bronchitis, 1.7% or ≥100/µl), osteoporosis (2.4% or ≥140/µl), mental illness 6.1% (or ≥400/µl), dust exposure (2.2% or ≥240/µl) and ex-smoker (1.3% or ≥100/µl).

CONCLUSIONS

The relatively higher EOS group (≥2% or ≥100/µl) was associated with fewer complications, mild airflow limitation, a tendency of noninfectious inflammation, and lower 3-year mortality. Eosinophils can not only guide clinical treatment but also be an indicator of predicting clinical outcome and prognosis in AECOPD patients.

Patients with Chronic Obstructive Pulmonary Disease and Evidence of Eosinophilic Inflammation Experience Exacerbations Despite Receiving Maximal Inhaled Maintenance Therapy

Background

Some patients with chronic obstructive pulmonary disease (COPD) experience frequent exacerbations despite maximal inhaled therapy (“triple therapy”), possibly leading to high health care resource utilization (HCRU).

Aim

Describe characteristics, future HCRU, and mortality of patients with COPD who experience frequent exacerbations despite triple therapy; characterize individuals who may be candidates for biologic therapies.

Methods

This descriptive observational study used primary care data of patients aged ≥40 years in the United Kingdom receiving maintenance therapy for COPD who had ≥1 year of data prior to index date and ≥1 year of follow-up data. We described these patients’ clinical and demographic characteristics, including blood eosinophil counts (BEC), pattern of exacerbations, hospitalizations, and corticosteroid exposure, as well as future exacerbations, hospitalizations, and death.

Results

Of 43,753 patients with maintenance-treated COPD, 6480 experienced exacerbations despite ≥3 months of triple therapy. Of these, 5669 had available BEC: 1287 (22.7%) had BEC ≥250 cells/µL and ≥3 exacerbations in the year prior to the index date; 471 (36.6%) received ≥4 acute courses of oral corticosteroids. Patients with a pattern of high disease burden continued to have high disease burden: 51.1% experienced ≥3 exacerbations and 2.6% experienced ≥3 hospitalizations. Patients who experienced exacerbations despite triple therapy had a significantly higher risk of COPD-related death than other maintenance-treated patients (5.8% vs 2.1%).

Conclusion

Nearly one-quarter of patients receiving triple therapy for COPD who experienced frequent exacerbations had elevated BEC and ≥3 exacerbations, suggesting a potential mechanism of persistent eosinophilic inflammation that could be a target for eosinophil-depleting biologic therapy.

Prognostic risk factors for moderate-to-severe exacerbations in patients with chronic obstructive pulmonary disease: a systematic literature review

Background

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. COPD exacerbations are associated with a worsening of lung function, increased disease burden, and mortality, and, therefore, preventing their occurrence is an important goal of COPD management. This review was conducted to identify the evidence base regarding risk factors and predictors of moderate-to-severe exacerbations in patients with COPD.

Methods

A literature review was performed in Embase, MEDLINE, MEDLINE In-Process, and the Cochrane Central Register of Controlled Trials (CENTRAL). Searches were conducted from January 2015 to July 2019. Eligible publications were peer-reviewed journal articles, published in English, that reported risk factors or predictors for the occurrence of moderate-to-severe exacerbations in adults age ≥ 40 years with a diagnosis of COPD.

Results

The literature review identified 5112 references, of which 113 publications (reporting results for 76 studies) met the eligibility criteria and were included in the review. Among the 76 studies included, 61 were observational and 15 were randomized controlled clinical trials. Exacerbation history was the strongest predictor of future exacerbations, with 34 studies reporting a significant association between history of exacerbations and risk of future moderate or severe exacerbations. Other significant risk factors identified in multiple studies included disease severity or bronchodilator reversibility (39 studies), comorbidities (34 studies), higher symptom burden (17 studies), and higher blood eosinophil count (16 studies).

Conclusions

This systematic literature review identified several demographic and clinical characteristics that predict the future risk of COPD exacerbations. Prior exacerbation history was confirmed as the most important predictor of future exacerbations. These prognostic factors may help clinicians identify patients at high risk of exacerbations, which are a major driver of the global burden of COPD, including morbidity and mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02123-5.

Blood Eosinophils and Chronic Obstructive Pulmonary Disease: A GOLD Science Committee 2022 Review

COPD is a heterogeneous condition. Some patients benefit from treatment with inhaled corticosteroids (ICS) but this requires a precision medicine approach, based on clinical characteristics (phenotyping) and biological information (endotyping) in order to select patients most likely to benefit. The GOLD 2019 report recommended using exacerbation history combined with blood eosinophil counts (BEC) to identify such patients. Importantly, the relationship between BEC and ICS effects is continuous; no / small effects are observed at lower BEC, with increasing effects at higher BEC. The GOLD 2022 report has added additional evidence and recommendations concerning the use of BEC in COPD in clinical practice. Notably, associations have been demonstrated in COPD patients between higher BEC and increased levels of type-2 inflammation in the lungs. These differences in type-2 inflammation can explain the differential ICS response according to BEC. Additionally, lower BEC are associated with greater presence of proteobacteria, notably haemophilus, and increased bacterial infections and pneumonia risk. These observations support management strategies that use BEC to help identify subgroups with increased ICS response (higher BEC) or increased risk of bacterial infection (lower BEC). Recent studies in younger individuals without COPD have also shown that higher BEC are associated with increased risk of FEV1 decline and the development of COPD. Here we discuss and summarise the GOLD 2022 recommendations concerning the use of BEC as a biomarker that can facilitate a personalised management approach in COPD.

Long‐term oxygen treatment need is less frequent in eosinophilic COPD patients

Introduction

Methods

Results

Conclusion

Identifying COPD in routinely collected electronic health records: a systematic scoping review

Although routinely collected electronic health records (EHRs) are widely used to examine outcomes related to COPD, consensus regarding the identification of cases from electronic healthcare databases is lacking. We systematically examine and summarise approaches from the recent literature. MEDLINE via EBSCOhost was searched for COPD-related studies using EHRs published from January 1, 2018 to November 30, 2019. Data were extracted relating to the case definition of COPD and determination of COPD severity and phenotypes. From 185 eligible studies, we found widespread variation in the definitions used to identify people with COPD in terms of code sets used (with 20 different code sets in use based on the ICD-10 classification alone) and requirement of additional criteria (relating to age (n=139), medication (n=31), multiplicity of events (n=21), spirometry (n=19) and smoking status (n=9)). Only seven studies used a case definition which had been validated against a reference standard in the same dataset. Various proxies of disease severity were used since spirometry results and patient-reported outcomes were not often available. To enable the research community to draw reliable insights from EHRs and aid comparability between studies, clear reporting and greater consistency of the definitions used to identify COPD and related outcome measures is key.

Blood Eosinophils and Clinical Outcomes in Patients With Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Propensity Score Matching Analysis of Real-World Data in China

Background and Objective: Elevated eosinophils in chronic obstructive pulmonary disease (COPD) are recognized as a biomarker to guide inhaled corticosteroids use, but the value of blood eosinophils in hospitalized exacerbations of COPD remains controversial. This study aimed to evaluate the accuracy of eosinophils in predicting clinical outcomes in acute exacerbation of COPD (AECOPD).

Methods: We analyzed data from the acute exacerbation of chronic obstructive pulmonary disease inpatient registry (ACURE) study, which is an ongoing nationwide multicenter, observational real-world study in patients admitted for AECOPD. Data collected between January 2018 and December 2019 in 163 centers were first reviewed. The eligible patients were divided into eosinophilic and non-eosinophilic groups, according to blood eosinophil with 2% of the total leukocyte count as the threshold. Propensity score (PS) matching was performed to adjust for confounders.

Results: A total of 1,566 patients (median age: 69 years; 80.3% male) were included and 42.7% had an eosinophilic AECOPD. Eosinophil count <2% was associated with the development of respiratory failure and pneumonia. After PS matching, 650 pairs in overall patients, 468 pairs in patients with smoking history and 177 pairs in patients without smoking were selected, respectively. Only in patients with smoking history, the non-eosinophilic AECOPD was associated with longer median hospital stays (9 vs. 8 days, P = 0.034), higher dosage of corticosteroid use, higher economic burden of hospitalization, and poorer response to corticosteroid therapy compared to the eosinophilic AECOPD. No significant difference was found in patients without smoking. Eosinophil levels had no relationship with the change of COPD Assessment Test scores and readmissions or death after 30 days.

Conclusion: Elevated eosinophils were associated with better short-term outcomes only in patients with a smoking history. Eosinophil levels cannot be confidently used as a predictor alone for estimating prognosis.

Effect of internet-based self-management on pulmonary function rehabilitation and living quality in patients with chronic obstructive pulmonary disease

OBJECTIVE

This study explored and analyzed the effect of Internet-based self-management on pulmonary function rehabilitation and living quality in patients with chronic obstructive pulmonary disease (COPD).

METHODS

Altogether, 106 stable-staged COPD patients admitted to our hospital from June 2018 to September 2019 were enrolled as the research subjects, and divided into the control group (n=51) and the observation group (n=55) according to the order of visit. The control group received conventional health education, and the observation group was treated with an educational model by Internet-based self-management. Afterwards, the changes of self-management ability, pulmonary function and living quality before and after intervention were compared between the two groups.

RESULTS

The scores of each dimension of self-management behavior in both groups of patients after intervention were critically higher than those prior to intervention (P<0.05), and the scores in observation-group patients were remarkably higher than thoes in control-group patients (P<0.05). Besides, the two groups of subjects were observed with elevated pulmonary function indexes FVC, FEV1 and 6MWD after intervention compared with that in prior-intervention (P<0.05), and the indexes in the observation-group after intervention were obviously higher than those in the control-group (P<0.05). In addition, the scores of each dimension of living quality in both groups after the intervention had a conspicuously rise compared with the prior-intervention period (P<0.05), and the scores in the observation group were remarkably lower than those in the control group (P<0.05). The satisfaction in observation group was obviously higher than that in control group (P<0.05).

CONCLUSION

Internet-based self-management can effectually improve the self-management ability of COPD patients. It is conducive to improve the patients' pulmonary function, and their living quality, thus it is worthy of clinical popularization and application.

Disease burden of eosinophilic airway disease: Comparing severe asthma, COPD and asthma-COPD overlap

BACKGROUND AND OBJECTIVE

There is less understanding of phenotypes and disease burden in asthma-COPD overlap (ACO) than either disease alone. Blood eosinophils may help identify the patients in the clinic with eosinophilic airway inflammation. The potential value of this approach requires an understanding of the illness burden associated with eosinophilic ACO, eosinophilic severe asthma and eosinophilic COPD, defined by blood eosinophils.

METHODS

Participants from studies of multidimensional assessment in airway disease were pooled to identify patients with ACO (n = 106), severe asthma (n = 64) and COPD alone (n = 153). Patients were assessed cross-sectionally for demographic and clinical characteristics, including disease burden indicators such as health-related quality of life (HRQoL) and past-year exacerbation. Eosinophilic patients were identified using different thresholds of blood eosinophil count.

RESULTS

Using a blood eosinophil count ≥0.3 × 10⁹ /L, 41% had eosinophilic airway disease: 55% in ACO, 44% in severe asthma and 29% in COPD. Blood and sputum eosinophils were moderately correlated (r_s = 0.51, n = 257, P < 0.001). Burden of disease was similar between eosinophilic and non-eosinophilic airway diseases, with poor HRQoL and high number of past-year exacerbations. Burden of disease was similar across eosinophilic severe asthma, COPD and ACO. Eosinophilic COPD tended to have poorer health status than eosinophilic ACO and severe asthma; however, in context of a high prevalence of eosinophilic ACO, cumulative population-level burden of eosinophilic disease was greater in ACO.

CONCLUSION

Disease burden across eosinophilic ACO, eosinophilic severe asthma and eosinophilic COPD was high, particularly cumulative population-level burden in ACO. Factors beyond airway inflammation may drive disease burden in severe patients.

Clinical And Economic Burden Of Eosinophilic COPD In A Large Retrospective US Cohort

Purpose

We sought to describe clinical and economic outcomes for COPD patients by blood eosinophil (EOS) count.

Methods

This retrospective cohort study of COPD patients used data from the Practice Fusion electronic medical records (EMR) database linked to Symphony Health Solutions transactional pharmacy, medical, outpatient, and inpatient claims data to evaluate COPD-related and all-cause health care resource utilization and cost in the 12-month period following the date of each patient’s greatest recorded blood eosinophil count during the 27-month period from January 2014 to March 2016. A post-index moderate exacerbation was defined as an outpatient or emergency care visit for COPD and a prescription for oral corticosteroid and/or antibiotics within 10 days of the visit. Severe exacerbation was defined as an inpatient hospitalization with COPD as primary diagnosis.

Results

Of 48,090 EMR patients, 39,939 (83.1%) had a charge in the claims data both pre- and post-index (mean age 67.2 years, 58.3% female), 17,397 (43.6%) had EOS ≥220 cells/µL. Moderate and severe exacerbations were more frequent for patients with EOS≥220 cells/µL compared with those with EOS <220 cells/µL (moderate: 6.8% vs 6.1%, p<0.05; severe: 3.1% vs 2.5%, p<0.001). After adjustment for baseline clinical characteristics, each 100-unit increase in EOS count was associated with a significant 2.24% increase in total all-cause costs and 4.54% increase in total COPD-related costs (p<0.001 for both). COPD-related costs were significantly greater for patients with an EOS count of ≥220 cells/µL compared with those with EOS <220 cells/µL (p<0.001). These costs appear to have been driven by a greater percentage of patients in the ≥220 cells/µL cohort with COPD-related resource use including hospitalization, office visits, ambulatory procedures and pharmacy prescriptions.

Conclusion

COPD patients with EOS counts ≥220 cells/µL were more likely to have had moderate or severe exacerbations and greater cost of care than those with EOS <220 cells/µL.