Clinical Adult Literature Updates from March 2015

Effects of Continuous Positive Airway Pressure Therapy on Glycaemic Control, Insulin Sensitivity and Body Mass Index in Patients with Obstructive Sleep Apnoea and Type 2 Diabetes: A Systematic Review and Meta-Analysis

In this systematic review and meta-analysis of six studies (2 RCT and 4 observational), use of CPAP had a significant effect on improvement in insulin sensitivity in patients with OSA and type 2 diabetes mellitus. However, this effect was note seen on the change in HbA1c or BMI. More randomized controlled trials are needed to evaluate the hypothesis whether OSA treatment improves glycemic control and long-term complications in this special patient population.

Risk Factors for Automobile Accidents Caused by Falling Asleep While Driving in Obstructive Sleep Apnea Syndrome

In a multivariate analysis, risk factors for automobile accidents caused by falling asleep while driving were examines in patients with OSA, and compared to simple snorers (AHI<5). The severity of Epworth Sleepiness Score and self-reported frequency of feeling drowsy while regular driving and working were associated with automobile accidents caused by falling asleep while driving. The association was more severe with increasing severity of OSA as determined by the AHI. This study contributes to the evidence in support of treatment of OSA in patients with self-reported sleepiness.

Trazodone Effects on Obstructive Sleep Apnea and NREM Arousal Threshold

In this randomized controlled, cross-over trial, 15 patients with OSA (AHI>10) were randomized to receive either trazodone (100mg) or placebo. Using an epiglottic catheter, arousal threshold was calculated as the nadir pressure prior to spontaneous EEG arousals related to respiratory events. Compared to placebo, trazodone resulted in a significant reduction the AHI (38.7 vs. 28.5 events/hr, P=0.041), without worsening hypoxemia or respiratory event duration. These findings suggest that trazodone could be effective therapy for OSA patients without worsening hypoxemia, by increasing the arousal threshold, improving the AHI with minimal effect on nocturnal hypoxemia. However, larger scale trials are needed to conclusively establish this relationship.

Impact of Obstructive Sleep Apnea on Cardiovascular Events After Coronary Artery Bypass Surgery

This study of 67 patients who underwent CABG, of whom 56% had OSA found that there was no difference in short-term (30 day) postoperative Major Adverse Cardiac or Cerebrovascular Events (MACCE), however MACCE (new revascularization, episodes of typical angina and atrial fibrillation were more common in patients with than without OSA in the long-term (up to 6.1 year) follow-up.

Effect of Below-the-Knee Compression Stockings on Severity of Obstructive Sleep Apnea

In this trial 45 patients with OSA were randomized to wear below-the-knee compression stockings or to a control group for 2 weeks. Polysomnography was done at baseline and at 2 weeks. The AHI decreased significantly more in the compression stockings group compared to the control group.

Perioperative Management of Obstructive Sleep Apnea: A Survey of Puerto Rico Anesthesia Providers

The authors published results of “a questionnaire (…) given to participants at the annual meeting of anesthesiology in Puerto Rico” with the goal to elucidate perioperative OSA practices. They concluded “there is a significant heterogeneity in the current clinical practice. The main barriers identified to achieve current recommendations were lack of institutional policies, awareness of current guideline, formal training in management of OSA, and access to a sleep specialist.