An unexpected role for serum uric acid as a biomarker for severity of asthma exacerbation

Although the increased uric acid (UA) levels in bronchoalveolar lavage fluid and pulmonary tissue homogenate in asthmatic patients or animal models are well established, changes in serum UA(sUA) levels during asthma exacerbation are uncertain.

This study aims to investigate the change of sUA levels during asthma exacerbation and the association between sUA and lung function.

A retrospective study was performed on 217 asthma exacerbation patients at the Department of Respiratory Medicine, West China Hospital of Sichuan University, China from 2008 till 2012. Another 142 healthy people, who participated in a health check at the same center in 2011 and 2012, served as controls.

Asthmatic patients during acute exacerbation had significantly higher sUA levels, compared to the remission period and healthy controls [(301.35±92.12)μmol/L vs. (185.74±56.89) μmol/L vs. (128.06±31.56)μmol/L respectively; p < 0.001]. In addition, patients with severe asthma exacerbation had higher sUA levels than those with moderate exacerbation [(341.54±86.27 vs. 265.44±62.78) μmol/L; p < 0.001], and patients with moderate exacerbation had higher sUA levels than those with mild exacerbation [(265.44±62.78 vs. 200.10±44.71) μmol/L; p < 0.001]. Correlation analysis revealed that sUA was negatively associated with lung function (r = -0.507, p < 0.001).

sUA levels increased at onset of asthma exacerbation, subsided during the course of exacerbation, and had a negative association with lung function. sUA may be a valuable biomarker for the severity of asthma exacerbation.