Lower mean corpuscular hemoglobin levels as a predictive factor of future exacerbations in patients with chronic obstructive pulmonary disease.

Background: Chronic obstructive pulmonary disease (COPD) is a pulmonary and systemic inflammatory disease, and the management of systemic comorbidities is important. We previously reported that a lower mean corpuscular hemoglobin concentration (MCHC) at admission was an independent prognostic factor for death in patients with COPD exacerbation. This study aimed to determine the association between MCHC levels and prognosis in patients with stable COPD.

Methods: Overall, 200 stable patients with COPD (mean age; 71.0 ± 8.4 years, male; 93.5%) from January 2014 to March 2020 who were followed up for 4.6 ± 0.7 years were included. During the observation period, 70 patients experienced COPD exacerbations.

Results: Significantly lower body mass index and more severe pulmonary function were observed in patients with COPD exacerbations than those without. The serum levels of aspartate aminotransferase and alanine aminotransferase, lymphocyte counts, and hemoglobin and MCHC levels in peripheral blood in patients with COPD exacerbation were significantly lower than those in patients without exacerbations. Multiple logistic regression analysis revealed that a lower MCHC level was an independent predictive factor of COPD exacerbations during the observation period, even after adjusting age, BMI, ACO merger, COPD grade, and emphysema severity, which were significantly different in univariate logistic regression analysis.

Conclusion: MCHC levels are a significant biomarker for assessing the future risk of exacerbations in patients with COPD, indicating usefulness of measurement of MCHC levels in the management of patients with COPD.