Paraoxonase-1 in stable chronic obstructive pulmonary disease: a systematic review and meta-analysis

INTRODUCTION: Oxidative stress plays a critical pathophysiological role in chronic obstructive pulmonary disease (COPD). An impairment in antioxidant defense systems, which include the enzyme paraoxonase1 (PON-1), have been reported in COPD patients. This systematic review and meta-analysis investigated the association between serum PON1 and COPD. EVIDENCE ACQUISITION: A systematic search was performed using the following terms and their combination: "paraoxonase-1" or "PON-1" and "chronic obstructive pulmonary disease" or "COPD" in PubMed, Web of Science, Scopus, and Google Scholar, from inception to October 2021. Standardized mean differences (SMDs) of serum PON-1 concentrations between stable COPD patients and non-COPD subjects were calculated. EVIDENCE SYNTHESIS: Thirteen studies were included in the meta-analysis. Pooled results showed that serum PON-1 concentrations were significantly lower in patients with COPD (SMD=-1.12, 95% CI: = 1.72 to = 0.53; P<0.001). CONCLUSIONS: The observed reduction of PON-1 concentrations in COPD patients supports the presence of an impaired antioxidant defense system in this group.