Serum uric acid as a biomarker for prediction of outcomes of patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease

Abstract

Serum uric acid, the final product of purine degradation, has been shown to be increased in the hypoxic state as well as in systemic inflammation including patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to assess the possible role of serum uric acid as a biomarker for the prediction of outcome of patients hospitalized for acute exacerbation of COPD (AECOPD). Serum uric acid levels were measured in 115 eligible AECOPD patients on admission. The primary end-point was all-cause mortality at 30 days. The secondary outcomes included the length of hospital stay, need for noninvasive ventilation, or ICU admission within 30 days. Serum uric acid presented an area under the receiver operating characteristic curve of 0.721 (95% confidence interval: 0.63–0.80) for the prediction of 30-day mortality in patients with AECOPD, with a sensitivity of 0.82 and a specificity of 0.61 for the cutoff point greater than 6.9 mg/dl (P = 0.021). Also, patients with higher serum uric acid levels required longer hospitalization and more often required the use of noninvasive ventilation and ICU admission at 30 days. In addition, serum uric acid levels were higher in patients with more severe airflow limitation, patients with cardiovascular comorbidity, and among frequent exacerbators. High serum uric acid levels on admission were associated with increased 30-day mortality in patients with AECOPD. The results of this work suggest a possible role for serum uric acid in the identification of COPD patients at an increased risk of adverse outcomes who may need early intensive management. Egypt J Broncho 2014 8:115–120