Systematic review on recent potential biomarkers of chronic obstructive pulmonary disease

Evaluation of the cross-sectional area of small pulmonary vessels in the diagnosis of chronic obstructive pulmonary disease by quantitative computed tomography: A case-control study

Patients with chronic obstructive pulmonary disease (COPD) have a reduced cross-sectional area (CSA) of small pulmonary vessels and decreased pulmonary function test (PFT) indexes. This study investigated the value of small pulmonary vessel CSA in diagnosing and evaluating the severity of COPD and its correlation with PFT.This retrospective case-control study included patients with COPD who underwent multi-slice spiral computed tomography (CT) between March 2015 and December 2018. COPD severity was graded. Patients with normal CT results were included as controls. The CSA of small pulmonary vessels at the sub-segmental (5-10 mm2) and sub-sub-segmental (<5 mm2) levels was measured. Receiver operating characteristic (ROC) curves were used to evaluate the effect of CSA for COPD risk prediction. The correlation between CSA% and PFT indexes was evaluated.There were 124 and 106 patients in the COPD and control groups, respectively. The %CSA <5 and %CSA5-10 were smaller in the COPD group than in controls (P  < .05). The %CSA <5 in each subgroup stratified by COPD severity was smaller than in controls (P  < .05). The % CSA5-10 was significantly smaller in the moderate and severe groups than in controls (P  < .05). At 0.655%CSA <5 cut-off, the ROC area under the curve (AUC) was 0.765. For %CSA5-10, a 0.565 cut-off led to an AUC of 0.752. Both %CSA <5 and %CSA5-10 were positively correlated with all PFT indexes (r = 0.180-0.462, all P  < .05).CSA was positively correlated with PFT. Analysis of small pulmonary vessel CSA based on CT images contributes to diagnosing and assessing the severity of COPD.

Eosinophilic phenotype was associated with better early clinical remission in elderly patients but not middle-aged patients with acute exacerbations of COPD

BACKGROUND

There is limited evidence of the relationship between peripheral blood eosinophils and clinical remission of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) at different ages, especially in elderly patients, which was the objective of the present study.

METHODS

This retrospective study stratified patients by age (elderly patients >65 years old or middle-aged patients between 45 and 65 years old) and analysed the relationship between blood eosinophils (≥2% or <2%) and AECOPD clinical remission at observing time points of 7, 14, 21 and 28 days of hospitalisation. Student's t tests, Mann-Whitney U tests, Chi-squared or Fisher's exact tests were conditionally used to compare difference between groups. The unadjusted or adjusted Cox proportional hazards model was used to analyse the association between blood eosinophilic levels and cumulative clinical remission.

RESULTS

Of 703 AECOPD cases analysed, 616 were elderly people (>65 years), 312 of whom had eosinophilic exacerbations. There were statistically significant differences in leucocytes, eosinophils, neutrophils, lymphocytes, monocytes, high-sensitivity C-reactive protein levels (hs-CRP), and hospital costs between groups (P < .05, respectively). According to the chi-square analysis, eosinophilic exacerbation had a higher clinical remission rate at 7, 14 and 21 days (all P < .05), but not 28 days (P > .05). Among analysis through adjusted Cox proportional hazards model, eosinophilic exacerbation was significantly associated with a higher cumulative remission rate in elderly patients at 7, 14, 21 days (all P < .05), but not 28 days (P > .05). No significant association was observed in meddle-aged patients at any time points (all P > .05).

CONCLUSION

Eosinophilic exacerbation was associated with better early clinical remission of AECOPD patients during hospitalisation. As stratified by ages, similar results were observed in elderly patients but not middle-aged patients. Blood eosinophils at different ages may be valuable in personalised management for AECOPD.

Evolving Concepts in Chronic Obstructive Pulmonary Disease Blood-Based Biomarkers

In recent years, there has been a great deal of interest in the identification and validation of blood-based biomarkers for clinical use in chronic obstructive pulmonary disease (COPD). We now have panels of blood biomarkers that potentially hold great promise as they show statistically significant associations with COPD, but biomarkers for the diagnosis of COPD remain elusive. In fact, they are yet to demonstrate sufficient accuracy to be accepted in clinical use, and many are not specific to COPD but more related to inflammation (e.g. interleukin-6) or associated with other chronic diseases such as diabetes (e.g. soluble receptor for advanced glycation endproducts [sRAGE]). Although no single blood-based biomarker has demonstrated clinical utility for either the diagnosis or progression of COPD, it has been suggested that combinations of individual markers may provide important diagnostic or prognostic information; however, the interpretation of COPD biomarker results still requires thought and many questions remain unanswered.