The Impact of Comorbidities on the Length of Hospital Treatment in Patients with Chronic Obstructive Pulmonary Disease

Introduction: The aim of this study was to assess the relationship between the incidence of comorbidities of chronic obstructive pulmonary disease (COPD) and the duration of hospital stay due to acute AE COPD in a longitudinal prospective study. Material and methods: We evaluated the number of re-hospitalizations, length of stay, and number of comorbidities in 464 consecutive COPD patients admitted to the tertiary respiratory hospital due to AE COPD enrolled in a longitudinal prospective study from 2005 to 2009. Results: GOLD II stage COPD patients had 4.1 ± 1.2 comorbidities (p = 0.002), stage III 3.4 ± 1.3, and stage IV 3.6 ± 1.2 comorbidities. The duration of hospital stay (median) was longer in more severe conditions. Duration of hospitalization correlated with the urea level (r = 0.19 p < 0.001), pCO₂ (r = 0.193, p = 0.0003), HCO₃ (r = 0.25, p < 0.0001), haemoglobin (r = –0.18, p < 0.001), and haematocrit (r = –0.13, p = 0.008). Patients with the risk of readmissionhad a more severe GOLD stage and were hypercapnic (pCO₂ = 47.6 mm Hg vs. 43.9 mm Hg in those withouthospitalization). Conclusions: Haemoglobin level, hypercapnia, and renal function are predictors of prolonged hospitalization. Patients with amore severe airflow limitation and a higher pCO₂ level reveal an increased risk of readmission to hospital. More severedisease stage and clinical diagnosis of cor pulmonale or bronchiectasis were related to longer hospital stay.