Role of galectin-3 as a biomarker in obstructive sleep apnea: a systematic review and meta-analysis

BackgroundBecause obstructive sleep apnea (OSA) is a prevalent condition, biomarkers for OSA would be very useful. Galectin-3 has gained attention as a marker for several diseases. The aim of this study was to investigate the association between circulating galectin-3 levels and OSA.MethodsPubMed, Scopus, Embase, and Web of Science were explored to find the studies evaluating galectin-3 in OSA and controls, within different severities of OSA, or before and after continuous positive airway pressure (CPAP) treatment in cases with OSA. We used random-effect meta-analysis to calculate standardized mean differences (SMD) along with 95% confidence intervals (CI). Newcastle-Ottawa Scale was used assessment of the risk of bias in studies.ResultsAn initial search resulted in 289 results. After exclusion of duplicate studies, screening of titles/abstracts and assessments of full texts, six studies were included comprised of 987 cases with a mean age of 54.4 years. Meta-analysis showed that there were significantly higher galectin-3 circulating levels in patients with OSA than in healthy controls (SMD 0.80, 95% CI 0.30 to 1.31, p value < 0.01). Severe OSA was related to higher levels of galectin-3, in comparison to non-severe OSA (SMD 0.76, 95% CI 0.29 to 1.22, p value < 0.01). CPAP therapy also significantly reduced galectin-3 peripheral levels in patients with OSA (SMD - 3.55, 95% CI - 6.90 to - 0.20, p value = 0.04).ConclusionThe findings suggest that Galectin-3 may have potential utility as a biomarker in patients with OSA. Further research is needed to demonstrate its role in pathophysiology, as well as its possible use in diagnosis and prognosis.