Efficacy of continuous positive airway pressure for obstructive sleep apnea in overweight patients with type 2 diabetes mellitus

Although the association between obstructive sleep apnea (OSA) and type 2 diabetes mellitus (T2DM) is well-established, the impact of continuous positive airway pressure (CPAP) therapy on glycemic control or metabolic profiles in T2DM patients with OSA is unclear. The objective of this study was to investigate metabolism-related parameters and diabetes treatment satisfaction following CPAP therapy for OSA in overweight patients with T2DM or impaired glycemic tolerance. This retrospective study included 16 overweight patients treated with CPAP for OSA by comparison of laboratory and anthropometric data between baseline (3 months before initiation of CPAP treatment) and at 3-and 6-months post-treatment, and by psychometric scores of DM treatment satisfaction using the Diabetes Treatment Satisfaction Questionnaire (DTSQ). Significant reductions in body weight and waist circumference were observed after initiating CPAP therapy (both P<0.001). Mean glycosylated hemoglobin (HbA1c) level measured at 3 months after CPAP therapy was lower than the baseline assessment, and the mean HbA1c level at 6 months post-treatment was lower than that at 3 months post-treatment (both P<0.05). In addition, fasting and postprandial plasma glucose levels decreased significantly at 3 months after CPAP therapy, remaining stable at 6 months (P=0.009). Furthermore, significant decreases in fasting insulin level (P=0.037), postprandial insulin level (P<0.001), and triglyceride level (P=0.002) were observed following CPAP. Finally, satisfaction with diabetes treatment improved significantly following initiation of CPAP therapy (P<0.001). CPAP for OSA improved anthropomorphic measures as well as glycemic control, insulin sensitivity and diabetes treatment satisfaction in overweight patients with T2DM or abnormal glucose metabolism.