Effect of Treatment of OSA With CPAP on Glycemic Control in Adults With Type 2 Diabetes: The Diabetes Sleep Treatment Trial (DSTT)

Objective: The effect of obstructive sleep apnea (OSA) treatment with continuous positive airway pressure (CPAP) on glycemic measures in patients with type 2 diabetes (T2D) remains unclear. We aimed to determine whether CPAP treatment of OSA improves glycemic measures in patients with T2D. Methods: This randomized controlled trial (N = 98) examined changes in glycemic measures following 12 weeks of active (n = 49) or sham (n = 49) CPAP and consideried participants' adherence to CPAP therapy (percentage of days with >4 hours use and average hours/day of use). Results: Baseline treatment groups were similar. Regarding the efficacy of active vs sham-CPAP over time, at 6 weeks, both groups had similar reductions in fructosamine (mean difference [MD], 95% confidence interval [CI]: CPAP-13.10 [-25.49 to-0.7] vs. sham-7.26 [-20.2 to 5.69]; P = .519) but different in HbA1c (CPAP-0.24 [-0.48 to-0.003] vs sham 0.15 [-0.10 to 0.4]; P = .027). At 12 weeks, reductions in HbA1c values were similar by group (CPAP-0.26 [-0.53 to 0.002] vs sham-0.24 [-0.53 to 0.04]; P = .924). HbA1c reductions were associated with a greater percentage of cumulative days of CPAP usage >4 hours per day (b [SE] = 0.006 [0.002]; P = .013) and cumulative hours of CPAP use (b [SE] = 0.08 [0.08]; P = .012). CPAP use of >7 hours was associated with a significant reduction in HbA1c (b [SE] 0.54 [0.16]; P = .0012). Conclusion: CPAP treatment of OSA did not result in sustained improved glycemic control compared to sham in the intent-to-treat analysis. CPAP adherence was associated with greater improvements in glycemic control. (c) 2022 AACE. Published by Elsevier Inc. All rights reserved.

Automated summary

This randomized controlled trial aimed to evaluate the effect of continuous positive airway pressure (CPAP) treatment on glycemic control in patients with type 2 diabetes (T2D) and obstructive sleep apnea (OSA). The results showed that CPAP treatment did not lead to sustained improvement in glycemic control in T2D patients, but adherence to CPAP therapy was associated with better glycemic control.