Does eosinophilia and neutrophil to lymphocyte ratio affect hospital re-admission in cases of copd exacerbation?

Introduction We aimed to assess the relationship between peripheral eosinophilia and neutrophil/lymphocyte ratio with hospital admissions and re-admissions with chronic obstructive pulmonary disease (COPD) exacerbations. Materials and methods An observational cohort study was carried out in a tertiary teaching hospital. Subjects with previously diagnosed COPD and who were admitted as outpatients with acute exacerbations were included. The subjects' characteristics, complete blood count (CBC) parameters, neutrophil to lymphocyte rate (NLR), C-reactive protein (CRP), mean platelet volume (MPV) on admission and re-admission within the first 28 days. Patients were grouped according to their peripheral blood eosinophilia levels; group 1, > 2% (eosinophilic), group 2, ≤ 2% (non-eosinophilic or neutrophilic). The recorded data from the two groups were compared. Result 1490 eligible COPD subjects were enrolled. Approximately 42% were classified as eosinophilic. The non-eosinophilic group had a significantly higher leukocyte count, neutrophil percentage, and NLR than the eosinophilic group. The NLR value in patients with repeat re-admissions was higher than the average, i.e., 4.50 (p= 0.001). MPV and CRP measured on admission and re-admission were similar in both groups. The rate of hospital re-admission within 28 days was significantly higher in patients with a non-eosinophilic attack. Conclusions When a patient is admitted to outpatients with a NLR greater than 4.50 and with a non-eosinophilic exacerbation they have an increased risk of re-admission in the first month. Higher NLR values and non-eosinophilic exacerbations may be helpful for the early detection of potential acute attacks in COPD patients, and may be indicators for antibiotic management.