Endocan as a biomarker for acute respiratory distress syndrome: A systematic review and meta-analysis

Background and AimsEndocan is a marker of endothelial damage. Data regarding the association of this proteoglycan and acute respiratory distress syndrome (ARDS) is discrepant. Hence, this study sought to investigate the possible correlation between serum/plasma endocan concentration and ARDS.MethodsA systematic review and meta-analysis of international online databases was conducted following PRISMA guidelines. PubMed, SCOPUS, Embase, and Web of Science were searched in March 2023, with the leading search terms being "ARDS" OR "respiratory distress" AND "endocan" and other associated terms. Studies that measured endocan levels in patients with ARDS and compared it with non-ARDS controls or within different severities of ARDS were included. We performed a random-effect meta-analysis for pooling the differences using standardized mean difference (SMD) and 95% confidence interval (CI).ResultsWe included 14 studies involving 1,058 patients. Those developing ARDS had significantly higher levels of endocan compared to those without ARDS (SMD: 0.47, 95% CI: 0.10-0.84, p = 0.01). Our meta-analysis of three studies found that endocan levels in ARDS nonsurvivors were significantly higher than in survivors (SMD: 0.31, 95% CI: 0.02-0.60, p = 0.03). Three studies investigated endocan levels in different severities of ARDS. Only one of these studies reported significantly higher endocan levels in patients with worsening acute respiratory failure at Day 15. The other two reported no significant association between ARDS severity and circulating endocan levels.ConclusionBlood endocan levels were significantly higher in patients with ARDS than those without. Additionally, among patients with ARDS, blood endocan values were significantly elevated in nonsurvivors compared to survivors. These findings could help researchers design future studies and solidify these findings and finally, clinicians to take advantage of measuring endocan in clinical settings for assessment of patients with ARDS.