Association between obstructive sleep apnea syndrome and metabolic syndrome: a severity-stratified meta-analysis.

Objective: This study aimed to systematically investigate the association between obstructive sleep apnea syndrome (OSAS) and metabolic syndrome (MetS), with a particular focus on severity-stratified analysis, in order to clarify the differential risks of MetS and its components (hypertension, hyperglycemia, etc. ) among patients with different levels of OSAS severity. Methods: A comprehensive literature search was conducted in Web of Science, PubMed, Cochrane, and Embase databases from their inception to June 1, 2025, using keywords related to "sleep apnea syndrome" and "MetS". After rigorous quality evaluation and data extraction of the included studies, a stratified meta-analysis by OSAS severity was performed using Stata 17.0 software.Subgroup analysis and meta-regression were further applied to explore heterogeneity sources, enhancing the reliability of results. Results: A total of 10 studies involving 10,205 participants were included. The meta-analysis revealed that the risk of developing MetS in patients with moderate-to-severe OSAS was 2.18 times higher than in those with mild OSAS (OR = 2.18, 95%CI:1.30-3.68, Conclusion: This study found that patients with moderate to severe OSAS have a 2.18 times higher risk of developing MetS than those with mild OSAS. Their risk of hypertension and hyperglycemia also goes up significantly. For patients with moderate to severe OSAS, it makes sense to prioritize MetS screening and start early intervention to lower their risk of developing MetS. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/.