Eosinopenia as a Prognostic Biomarker for Noninvasive Ventilation Use in COPD Exacerbations.

BACKGROUND: In recent years, blood eosinophils have been evaluated as a surrogate biomarker for eosinophilic airway inflammation and as a prognostic indicator of the outcomes of hospitalized COPD subjects. During an exacerbation of COPD, eosinopenia has been proposed as a prognostic marker of adverse outcomes. OBJECTIVES: The aim of the present post hoc analysis was to elucidate the effectiveness of blood eosinophils for predicting the need of NIV in subjects with COPD exacerbation. METHODS: Consecutive subjects admitted to a hospital for COPD exacerbation were included in the analysis. The eosinophil count from the first complete blood count was used to designate the eosinophil groups. The relationship between the clinical characteristics and blood eosinophil counts, as dichotomized using 150 cells/µL, was evaluated. Results Subjects with blood eosinophil number < 150 k/µL had a more severe disease on admission compared to subjects with ≥150 k/µL, regarding pH 7.400 (7.36, 7.44) vs. 7.42 (7.38, 7.45), p = 0.008, PO2/FiO2 levels 238.1 (189.8, 278.6) vs. 276.2 (238.2, 305.6), p < 0.001, CRP (mg/L) levels 7.3 (3.1, 19.9) vs. 3.5 (0.7, 7.8), p < 0.001 and required a longer hospital stay (days) 10.0 (8.0, 14.0) vs. 5.0 (3.0, 7.0) p < 0.001 respectively. The number of blood eosinophils correlated with the levels of CRP upon admission (p < 0.001, r = -0.334), with arterial pH upon admission (p < 0.030, r = 0.121), with PO2/FiO2 (p < 0.001, r = -0.248), and with duration of hospital stay (p < 0.001, r = -0.589). In the multinomial logistic regression analysis, blood eosinophil count < 150 k/µL was an independent predictor of the use of NIV during hospital stay. CONCLUSION: During COPD exacerbation, low blood eosinophil levels upon admission are related to more severe disease and can be used as a predictor of the need of NIV. Further prospective studies are needed to identify the use of blood eosinophil levels as a predictor of unfavorable outcomes.

Glycated Hemoglobin (HbA1c) as a Predictor of Outcomes during Acute Exacerbations of Chronic Obstructive Pulmonary Disease.

Systemic inflammation may be the common denominator between COPD and type 2 diabetes and may explain the correlation in both diseases' development and progress. The aim of this prospective observational study is to examine the prognostic value of glycated hemoglobin levels (HbA1c) and HbA1c-adjusted glycemic variables (glycemic gap, stress hyperglycemia ratio και modified stress hyperglycemia ratio) in an acute exacerbation of COPD (AECOPD) as well as in COPD disease's morbidity and mortality during the following year. We evaluated patients hospitalized only for COPD exacerbations. Levels of HbA1c and HbA1c-adjusted glycemic variables were recorded upon admission. The study outcomes included duration of hospital stay, need for mechanical ventilation and exacerbation outcome. All subjects were followed up for one year. A total of 156 patients were included in the study (74.4% men, age [mean ± SD] 72 ± 7 years). Patients (21.8%) had type 2 diabetes and 67.9% of patients were receiving ICS treatment. The median value of HbA1c was 5.9 (IQR: 5.4, 6.5). Necessity for mechanical ventilation was significantly higher for patients with lower values of HbA1c [median: 5.3 (IQR 5.02, 6.3) vs. 5.9 (IQR 5.5, 6.5), p = .038]. However, duration of hospitalization, death during hospitalization as well as the number of new exacerbation events, time to next exacerbation and mortality during the following year did not differ significantly. Moreover, none of the HbA1c-adjusted glycemic variables examined, demonstrated any statistical significance. In conclusion neither the preceding nor the present glycemic state exhibit a predictive value regarding short- or long-term outcomes of an AECOPD.

Blood eosinophils as predictor of outcomes in patients hospitalized for COPD exacerbations: a prospective observational study.

PURPOSE: In the present prospective multicentre observational study, we evaluated the potential role of blood eosinophils on the outcomes of patients hospitalized for COPD exacerbations. MATERIAL AND METHODS: Consecutive patients >40 years with a previous COPD diagnosis were recruited. Blood eosinophils were measured on admission prior to the initiation of treatment and were evaluated in three groups (<50, 50-149 and ≥150 cells/µL). Patients received standard care and were followed up for a year. RESULTS: A total of 388 patients were included (83.5% male, mean age 72 years). Patients with higher blood eosinophils had less dyspnoea (Borg scale), lower C-reactive protein (CRP) and higher PaO2/FiO2 (partial pressure for oxygen/fraction of inhaled oxygen), and were discharged earlier (median 11 vs. 9 vs. 5 days for patients with <50, 50-149 and ≥150 cells/µL, respectively). Patients with <50 cells/µL presented higher 30-day and 1-year mortality, whereas there were no differences in moderate/severe COPD exacerbations between the three groups. In a post hoc analysis, treatment with inhaled corticosteroids as per physicians' decision was associated with better exacerbation prevention during follow-up in patients with ≥150 cells/µL. CONCLUSIONS: Higher blood eosinophils were associated with better outcomes in hospitalized COPD patients, further supporting their use as a prognostic biomarker.