Therapeutic effect of laparoscopic sleeve gastrectomy on obstructive sleep apnea and relationship of type 2 diabetes in Japanese patients with severe obesity

Aims/Introduction: Obstructive sleep apnea (OSA) is among the most important obesity-related diseases, and offers the potential for accelerated the early onset and progression of type 2 diabetes. The aim of the present study was to clarify the therapeutic effect of laparoscopic sleeve gastrectomy on OSA in severely obese Japanese patients, and to find correlations between OSA improvements and β-cell function (BCF). Materials and Methods: Between September 2013 and December 2019, 61 patients who underwent laparoscopic sleeve gastrectomy were enrolled. The apnea–hypopnea index (AHI) was used to diagnose OSA. The tongue area, uvula area and other parameters were measured using cone-beam computed tomography. Regarding BCF parameters, the homeostasis model assessment of β-cell function, insulinogenic, Matsuda and disposition indexes were used to evaluate the improvement in BCF. Improvement of OSA was defined as AHI <15. Results: The improvement rate of OSA was 51.8% (29/56). The change in AHI was significantly correlated with the excess weight loss percentage (ρ = 0.501), changes in tongue area (ρ = 0.350) and uvula area (ρ = 0.341). Multivariate analysis showed that preoperative AHI and postoperative hemoglobin A1c were independent prognostic factors of OSA non-improvement. The homeostasis model assessment of β-cell function (P < 0.001), the insulinogenic index (P < 0.001) and the disposition index (P = 0.019) of patients with AHI of <15 were significantly higher than those in patients with AHI of ≥15. Conclusions: Laparoscopic sleeve gastrectomy is a promising procedure for severely obese patients with OSA. BCF recovery was found to be significantly higher in patients with OSA improvement.