Does Low Mean Corpuscular Hemoglobin Concentration Really Predict Mortality in Acute Exacerbations of Chronic Obstructive Pulmonary Disease?

Abstract

Background and Aim: Several studies have shown associations of low mean corpuscular hemoglobin concentration (MCHC) with mortality and poor clinical course in conditions associated with chronic inflammation such as cardiac failure and COPD. Thus, in this study we aimed to determine the link between MCHC and readmission mortality in a large patient population with minimum 1 year of follow-up. Methods: Clinical data at admission, laboratory data, number of admissions to emergency room due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD) following the discharge of the last patient recruited, number of admissions to pulmonology unit, and number of intensive care unit admissions between 2018 and 2019 were recorded. The follow-up duration ranged between 12 and 36 months. Results: A total of 339 patients were included. Based on a ROC analysis, the cut-off value for MCHC was 32.35 g/dl. Comparison of clinical data according to this cut-off value showed an increase in the incidence of pneumonia during admission, hypercapnic respiratory failure, need for non-invasive mechanical ventilation (NIV), and number of intensive care unit admissions within a 1 year period, as well as reduced survival in non-anemic subjects with MCHC ≤ 32.35 g/dL. In multivariate cox-regression analysis MCHC was not an independent predictor of mortality risk. Conclusion: We recommend careful monitoring and assessment of comorbidities in AECOPD patients with low MCHC but without anemia. MCHC was not found to be an independent predictor of mortality but there was a significant correlation between MCHC and survival in patients without anemia.