Serum uric acid level as a biomarker for chronic obstructive pulmonary disease: a meta-analysis

OBJECTIVE: To determine if there is a relationship between the levels of serum uric acid and the different Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages (1–4) classified by the severity of the airflow limitation in patients with stable chronic obstructive pulmonary disease (COPD). METHODS: Electronic databases, including PubMed®, Embase®, Web of Science™ and China National Knowledge Infrastructure (CNKI), were searched from inception to December 2018. Observational studies that reported serum uric acid levels in stable COPD patients were included. Two investigators independently extracted data and RevMan version 5.3 was used to carry out the statistical analyses. RESULTS: Seven studies with 932 stable COPD patients and 401 healthy control subjects were included in this meta-analysis. Serum uric acid levels were significantly higher in stable COPD patients compared with healthy control subjects (mean difference [MD] 1.91, 95% confidence interval [CI] 1.55, 2.28). Serum uric acid levels were significantly lower in the GOLD 1+2 subgroup compared with the GOLD 3+4 subgroup (MD −1.39, 95% CI −1.63, −1.15). CONCLUSION: Serum uric acid might be a useful biomarker for identifying disease severity in stable COPD patients, but further studies are needed to confirm this finding.