Metabolic Improvements Following Upper Airway Surgery in Obstructive Sleep Apnea: Association of Airway Improvement...

Background: Obstructive sleep apnea (OSA) is increasingly recognized as a systemic disorder associated with insulin resistance and elevated risk of type 2 diabetes. While continuous positive airway pressure (CPAP) is the standard therapy, its long-term metabolic benefits remain inconsistent. The metabolic impact of upper airway surgery is less well defined. Methods: In this retrospective study, 49 patients with polysomnography-confirmed OSA who underwent upper airway surgery were evaluated. Respiratory and metabolic parameters-including apnea-hypopnea index (AHI), fasting plasma glucose, fasting insulin, glycated hemoglobin (HbA1c), and homeostatic model assessment for insulin resistance (HOMA-IR)-were assessed preoperatively and at 6 months postoperatively. Associations between changes in AHI (ΔAHI) and insulin resistance (ΔHOMA-IR) were analyzed using correlation and receiver operating characteristic (ROC) analyses. Results: Significant improvements were observed in both respiratory and metabolic parameters. AHI decreased from 46.6 ± 25.8 to 20.7 ± 14.1 events/h (p < 0.001). Fasting plasma glucose, insulin levels, and HOMA-IR were significantly reduced postoperatively (all p < 0.05), while HbA1c showed a downward trend. Reduction in AHI was moderately correlated with improvement in insulin resistance (r = 0.527, p < 0.001). ROC analysis demonstrated modest discriminative ability of ΔAHI for identifying normalization of insulin resistance (AUC = 0.62). Conclusions: Upper airway surgery was associated with significant improvements in insulin resistance and glycemic parameters in patients with OSA. The correlation between airway improvement and metabolic change supports a physiological link between upper airway obstruction and insulin sensitivity. These findings suggest that upper airway surgery may represent a clinically relevant adjunct within multimodal strategies for metabolic risk reduction, particularly in patients unable to tolerate CPAP therapy.