How should we define and classify exacerbations in chronic obstructive pulmonary disease?

New markers in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), a global healthcare and socioeconomic burden, is a multifaceted respiratory disorder that results in substantial decline in health status and life quality. Acute exacerbations of the disease contribute significantly to increased morbidity and mortality. Consequently, the identification of reliable and effective biomarkers for rapid diagnosis, prediction, and prognosis of exacerbations is imperative. In addition, biomarkers play a crucial role in monitoring responses to therapeutic interventions and exploring innovative treatment strategies. Although established markers such as CRP, fibrinogen and neutrophil count are routinely used, a universal marker is lacking. Fortunately, an increasing number of studies based on next generation analytics have explored potential biomarkers in COPD. Here we review those advances and the need for standardized validation studies in the appropriate clinical setting.

Identifying acute exacerbations of chronic obstructive pulmonary disease using patient-reported symptoms and cough feature analysis

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are commonly encountered in the primary care setting, though the accurate and timely diagnosis is problematic. Using technology like that employed in speech recognition technology, we developed a smartphone-based algorithm for rapid and accurate diagnosis of AECOPD. The algorithm incorporates patient-reported features (age, fever, and new cough), audio data from five coughs and can be deployed by novice users. We compared the accuracy of the algorithm to expert clinical assessment. In patients with known COPD, the algorithm correctly identified the presence of AECOPD in 82.6% (95% CI: 72.9–89.9%) of subjects (n = 86). The absence of AECOPD was correctly identified in 91.0% (95% CI: 82.4–96.3%) of individuals (n = 78). The diagnostic agreement was maintained in milder cases of AECOPD (PPA: 79.2%, 95% CI: 68.0–87.8%), who typically comprise the cohort presenting to primary care. The algorithm may aid early identification of AECOPD and be incorporated in patient self-management plans.

A Proteomics-Based Analysis of Blood Biomarkers for the Diagnosis of COPD Acute Exacerbation

Purpose

The identification of blood biomarkers to diagnose acute exacerbation of chronic obstructive pulmonary disease (AECOPD) will have clinical utility. Here, we used a proteomics-based approach to identify biomarkers capable of identifying AECOPD.

Patients and Methods

This prospective, single-center pilot study enrolled 12 patients who came to Asan Medical Center (South Korea) via the outpatient clinic or emergency department with symptoms of AECOPD and were follow-up in the outpatient clinic during convalescence between 2015 and 2017. Paired blood samples collected from each patient during the treatment naïve AECOPD and convalescence stages were analyzed. A sequential window acquisition of all theoretical fragmentation spectra-mass spectrometry (SWATH-MS)-based proteome analysis was performed and a subset of the data were verified by ELISA.

Results

The SWATH-MS analysis identified 226 plasma proteins across all samples examined. The median coefficient of variation for triplicate technical replicates of each sample was 1.13 ± 1.38%, indicating high precision of the technique. Fold-change and paired t-test analyses revealed that 14 proteins were present at higher levels in the AECOPD samples than in the convalescence samples. A gene ontology analysis revealed that these proteins are involved in the acute-phase response. A total of 15 proteins were present at higher levels during the recovery (convalescence) stage than during the acute exacerbation phase, and gene ontology analysis revealed that these proteins are related to lipid metabolism and transport. Verification of the SWATH-MS data was performed using ELISAs for three proteins that were up-regulated in AECOPD, namely, LBP, ORM2, and SERPINA3. Among them, SERPINA3 (p = 0.005) was up-regulated significantly in AECOPD compared with the convalescence state.

Conclusion

Potential plasma biomarkers of AECOPD were discovered using the SWATH-MS proteomics method, and functional molecular associations were investigated. SERPINA3 could be a promising diagnostic biomarker for the early identification and tracking of AECOPD.

Comparison of patient-reported outcomes during acute exacerbations of chronic obstructive pulmonary disease

Introduction

The aim of this study was to investigate which patient-reported outcome measure was the best during the recovery phase from severe exacerbation of chronic obstructive pulmonary disease (COPD).

Methods

The Exacerbations of Chronic Pulmonary Disease Tool (EXACT), the COPD Assessment Test (CAT), the St George’s Respiratory Questionnaire (SGRQ), the Dyspnoea-12 (D-12) and the Hyland Scale (global scale) were recorded every week for the first month and at 2 and 3 months in 33 hospitalised subjects with acute exacerbation of COPD (AECOPD).

Results

On the day of admission (day 1), the internal consistency of the EXACT total score was high (Cronbach’s alpha coefficient=0.89). The EXACT total, CAT, SGRQ total and Hyland Scale scores obtained on day 1 appeared to be normally distributed. Neither floor nor ceiling effects were observed for the EXACT total and SGRQ total scores. The EXACT total score improved from 50.5±12.4 to 32.5±14.3, and the CAT score also improved from 24.4±8.5 to 13.5±8.4 during the first 2 weeks, and the effect sizes (ES) of the EXACT total and CAT score were −1.40 and −1.36, respectively. The SGRQ, Hyland Scale and D-12 were less responsive, with ES of −0.59, 0.96 and −0.90, respectively.

Discussion

The EXACT total and CAT scores are shown to be more responsive measures during the recovery phase from severe exacerbation. Considering the conceptual framework, it is recommended that the EXACT total score may be the best measure during the recovery phase from AECOPD. The reasons for the outstanding responsiveness of the CAT are still unknown.

Identification and assessment of COPD exacerbations

Chronic Obstructive Pulmonary Disease (COPD) exacerbations play a central role in the disease natural history of the disease, affecting its overall severity, decreasing pulmonary function, worsening underlying co-morbidities, impairing quality of life (QoL) and leading to severe morbidity and mortality. Therefore, identification and correct assessment of COPD exacerbations is paramount, given it will strongly influence therapy success. For the identification of exacerbations, several questionnaires exist, with varying degrees of complexity. However, most questionnaires remain of limited clinical utility, and symptom scales seem to be more useful in clinical practice. In the assessment of exacerbations, the type and degree of severity should be ascertained in order to define the management setting and optimize treatment options. Still, a consensual and universal classification system to assess the severity and type of an exacerbation is lacking, and there are no established criteria for less severely ill patients not requiring hospital assessment. This might lead to under-reporting of minor to moderate exacerbations, which has an impact on patients' health status. There is a clear unmet need to develop clinically useful questionnaires and a comprehensive system to evaluate the severity of exacerbations that can be used in all settings, from primary health care to general hospitals.

[Systemic inflammatory profile of smokers with and without COPD]

INTRODUCTION

Studies comparing the systemic inflammatory profiles of smokers with and without COPD present discordant findings.

AIM

To compare the systemic inflammatory profile of smokers with and without COPD.

METHODS

This is a cross-sectional comparative study. Two groups of active smokers of more than 10 pack-years were included: 56 consecutives stable COPD (postbronchodilator FEV₁/FVC<0.70) and 32 consecutives non-COPD (postbronchodilator FEV₁/FVC≥0.70). Smoking and clinical, anthropometric and spirometric data were noted. The following blood biomarkers were identified: leukocytes, hemoglobin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR). According to the levels (normal/abnormal) of these markers, two groups of smokers were formed. Quantitative and qualitative data were expressed, respectively, as means±SD and percentages.

RESULTS

Compared to the non-COPD group, the COPD group was older (56±12 vs. 65±8 years) and had a higher smoking consumption (30±18 vs. 52±31 pack-years). Compared to the non-COPD group, the COPD group had higher values of CRP (2.06±1.24 vs. 11.32±11.03mg/L), of ESR (9.59±8.29 vs. 15.96±11.56), of IL-6 (9.28±4.69 vs. 20.27±5.31ng/L) and of TNF-α (18.38±7.98ng/L vs. 8.62±3.72ng/L). Compared to the non-COPD group, the COPD group included higher percentages of smokers with elevated CRP (0 % vs. 32 %), with leukocytosis (6 % vs. 16 %), with higher levels of IL-6 (81 % vs. 98 %) or TNF-α (91 % vs. 100 %).

CONCLUSION

Smokers with COPD, compared to smokers free from COPD, have a marked systemic inflammation.

Do symptom-based questions help screen COPD among Chinese populations?

Spirometry is required to confirm a chronic obstructive pulmonary disease (COPD) diagnosis, but it is difficult to perform in resource-limited settings. This study aimed to evaluate symptom-based questions for screening of individuals with COPD among Chinese populations. We recruited 3969 adult subjects from the First Affiliated Hospital of Nanjing Medical University. Spirometric measurements of forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were collected to confirm the COPD diagnosis. A symptom-based questionnaire was administered to collect data related to COPD. The sensitivity and specificity together with the area under the curve (AUC) were calculated. The traditional IPAG eight-item questionnaire yielded an AUC of 0.80(95% CI: 0.78–0.82), with a sensitivity of 67.8% and specificity of 76.8%. After removing and adding questions, a revised eleven-item questionnaire exhibited a significantly increased diagnostic accuracy, with an AUC of 0.85(95% CI: 0.84–0.87). At the inflection point of the curve, it demonstrated a sensitivity of 82.5% and specificity of 72.9%. We showed that the revised symptom-based questionnaire could be used to screen individuals with a high likelihood of COPD among Chinese populations. Further validation is required before we claim it is a useful diagnostic for primary care populations.

COPD control: Can a consensus be found?

There are currently no reliable instruments for assessing the onset and progression of chronic obstructive pulmonary disease (COPD) or predicting its prognosis. Currently, a comprehensive assessment of COPD including several objective and subjective parameters is recommended. However, the lack of biomarkers precludes a correct assessment of COPD severity, which consequently hampers adequate therapeutic approaches and COPD control. In the absence of a definition of "well-controlled disease", a consensus regarding COPD control will be difficult to reach. However, COPD patient assessment should be multidimensional, and anchored in five points: control of symptoms, decline of pulmonary function, levels of physical activity, exacerbations, and Quality of Life. Several non-pharmacological and pharmacological measures are currently available to achieve disease control. Smoking cessation, vaccination, exercise training programs and pulmonary rehabilitation are recognized as important non-pharmacological measures but bronchodilators are the pivotal therapy in the control of COPD. This paper discusses several objective and subjective parameters that may bridge the gap between disease assessment and disease control. The authors conclude that, at present, it is not possible to reach a consensus regarding COPD control, essentially due to the lack of objective instruments to measure it. Some recommendations are set forth, but true COPD control awaits further objective assessments.

No significant detectable anti-infection effects of aspirin and statins in chronic obstructive pulmonary disease

BACKGROUND

Past studies have shown that aspirin and statins decrease the rate and severity of exacerbation, the rate of hospitalization, and mortality in chronic obstructive pulmonary disease (COPD). Although these studies are relatively new, there is evidence that new therapeutic strategies could prevent exacerbation of COPD.

TRIAL DESIGN

This article examines retrospectively the possibility of using aspirin and statins to prevent exacerbation and infection in patients with COPD.

METHODS

All patients with COPD were identified from hospital charts in the Department of Internal Medicine, Saarland University Medical Center, Germany, between 2004 and 2014.

RESULTS

The study examined 514 medical reports and secured a study population of 300 with COPD. The mean age was 69 ± 10 years (206 men, 68.7%, 95% CI, 63.4-73.9; 94 women, 31.3%, 95% CI, 26.1-36.6). The study results did not show a causal relationship between aspirin and statins and prevention of exacerbation and infection in patients with COPD.

CONCLUSION

In contrast, in this study, the exacerbation and infection rates increased under medication with aspirin and statins (p = 0.008).

Long-acting bronchodilator use after hospitalization for COPD: an observational study of health insurance claims data

Background

Treatment of stable chronic obstructive pulmonary disease (COPD) with long-acting bronchodilator (LABD) medications is recommended by the 2014 Global initiative for chronic Obstructive Lung Disease (GOLD) guidelines. The primary objective of this study was to examine LABD prescription fills after a COPD-related hospitalization.

Methods

This retrospective observational study used claims from Truven Health MarketScan^® Commercial and Medicare Supplemental databases. Patients (age ≥40, commercial; age ≥65, Medicare supplemental) had a first hospitalization with a primary COPD diagnosis between April 1, 2009 and June 30, 2011 (index hospitalization) and were continuously enrolled for 1 year before and 9 months after hospitalization. Patients were categorized according to pre-index and/or post-index pharmacy claims.

Results

A total of 27,738 patients had an index hospitalization and met inclusion/exclusion criteria. Of those, 19,783 patients had COPD as a primary or secondary diagnosis during the year before index hospitalization and were included in the analysis. Approximately one quarter of the patients (26.32%) did not fill a prescription for an LABD or short-acting bronchodilator both 90 days before and 90 days after hospitalization. During the 90-day pre-index period, 40.57% of patients filled an LABD (with or without a short-acting bronchodilator) prescription. Over half of the patients (56.88%) filled an LABD prescription at some point during the 180-day post-index period, but, of those, a significantly greater proportion of patients filled an LABD prescription in the 1- to 90-day post-index period than in the 91- to 180-day post-index period (51.27% versus 43.66%; P<0.0001).

Conclusion

A significant proportion of COPD patients in this study did not fill an LABD prescription before hospitalization for COPD. Moreover, hospitalization did not appear to greatly impact LABD initiation. Lastly, patients who did not fill an LABD prescription within the first 90 days posthospitalization were not likely to fill an LABD prescription later. Taken together, the results of this study suggest that many patients with COPD are undertreated.