Effect of dapagliflozin on obstructive sleep apnea in patients with type 2 diabetes: a preliminary study

OBJECTIVE: The aim of this case-control study was to assess the efficacy of dapagliflozin combined with metformin for type-2 diabetes mellitus (T2DM) with obstructive sleep apnea hypopnea syndrome (OSAHS). METHODS: A total of 36 patients with newly-diagnosed T2DM and OSAHS were randomized divided into two groups. Eighteen OSAHS patients with T2DM, who were treated with dapagliflozin and metformin, were assigned as the dapagliflozin group. These patients were given dapagliflozin and metformin for 24 weeks between February 2017 and February 2018. Another 18 OSAHS patients with T2DM, who were treated with glimepiride and metformin for 24 weeks, were assigned as the control group. Fasting plasma glucose (FPG) level, postprandial blood glucose (PPG), hemoglobin A1C (HbA1c), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), blood lipids, body mass index (BMI), blood pressure, apnea-hypopnea index (AHI), minimum oxygen saturation (LSpO(2)), and Epworth Somnolence Scale (ESS) score were measured before and at 24 weeks after the initiation of treatment. RESULTS: In the dapagliflozin group, triglyceride (TG), systolic pressure (SBP) and diastolic pressure (DBP) significantly decreased following treatment, while high-density lipoprotein cholesterol (HDL-C) significantly increased (P < 0.05). Furthermore, a reduction in AHI, an increase in LSpO(2) and a decrease in ESS score were observed in the dapagliflozin group (P < 0.05), but not in the control group. Moreover, blood glucose, HbA1c, HOMA-IR, and BMI significantly decreased in these two groups, and the decrease was more significant in the dapagliflozin group. CONCLUSION: These present results indicate that dapagliflozin can significantly reduce glucose, BMI, blood pressure and AHI, and improve hypoxemia during sleep and excessive daytime sleepiness, which thereby has potential as an effective treatment approach for OSAHS.