Continuous positive airway pressure and diabetes risk in sleep apnea patients: A systemic review and meta-analysis.

BACKGROUND: The study assessed the effect of continuous positive airway pressure (CPAP) therapy on the risk of developing type 2 diabetes by evaluating change in the homeostasis model assessment of insulin resistance (HOMA-IR) fasting blood glucose (FBG) and fasting insulin following CPAP treatment in non-diabetic patients and pre-diabetic with obstructive sleep apnea (OSA).

METHODS: Medline, PubMed, Cochrane, and EMBASE databases were searched until August 24, 2015. The analysis included randomized controlled trials (RCTs), two arm prospective studies, cohort studies, and retrospective studies. The primary outcome measure was change of HOMA-IR in pre-diabetic patients receiving CPAP treatment.

RESULTS: Twenty-three studies were included with 965 patients who had OSA. Nineteen studies were prospective studies and four were RCTs. CPAP therapy resulted in a significant reduction in the pooled standard difference in means of HOMA-IR (-0.442, P=0.001) from baseline levels compared with the control group. Change in FBG and fasting insulin from baseline levels was similar for the CPAP and control groups. For RCT studies (n=4), there was no difference in change in HOMA-IR or FBG levels from baseline between CPAP and control groups. The combined effect of RCTs showed that CPAP was associated with a significant reduction in change from baseline in fasting insulin than the control group (standardized diff. in means between groups=-0.479, P value=0.003).

CONCLUSION: These findings support the use of CPAP in non-diabetic and pre-diabetic patients with OSA to reduce change of HOMA-IR and possibly reduce the risk of developing type 2 diabetes in this patient population.