The US study found that nocturnal glucose levels in type 2 diabetics with OSA were reduced with CPAP therapy. It also found the sleeping interstitial glucose level of those with OSA was more stable during CPAP therapy.
50 per cent of patients with OSA have type 2 diabetes or impaired carbohydrate metabolism.
The study, published in the Journal of Clinical Sleep Medicine, looked at 20 type 2 diabetics. Most were obese, newly diagnosed with OSA and had no previous CPAP experience.
Glucose levels were monitored over two 36 hour sessions, which included a night in a sleep laboratory. In the first session, the patients’ OSA went untreated. The second session was conducted after the patient had been on CPAP for one to three months.
Sleeping glucose level, on average, decreased by 20mg after 21 days of CPAP. Sleeping glucose levels were also more stable after therapy, with standard deviation decreasing from 20 to 13mg.
The researchers said previous studies had shown that variability of the glucose level increases the risk of eye complications and death in type 2 diabetics.