Treating sleep apnea has been shown to reduce the risk of diabetes.

New research published online in the American Journal of Respiratory and Critical Care Medicine has found people with pre-diabetes — high blood sugar that puts them at high risk of developing Type 2 diabetes — who use a sleep-apnea device while sleeping have improved blood glucose levels.

The findings, by researchers at McGill University in Montreal, suggest use of a continuous positive airway pressure (CPAP) mask — a device that blows a constant pressure of air into the lungs during the night to help apnea sufferers breathe better — can stave off diabetes and help people with pre-diabetes.

"Our study showed that CPAP in patients with pre-diabetes can lower their risk of progressing to diabetes when CPAP is used for eight hours, a full night's sleep," said lead researcher, Sushmita Pamidi, M.D., a former fellow at the University of Chicago who is now on the faculty at McGill University in Montreal, Canada.

"Although eight hours of CPAP per night can be difficult to achieve in real-life, our results should provide a strong incentive for anyone with sleep apnea, especially pre-diabetic individuals, to improve adherence to their treatment for cardio-metabolic risk reduction." she said.

Pre-diabetes afflicts nearly 57 million Americans, putting them at risk for diabetes, which in turn increases the odds of cardiovascular disease and serious damage to the eyes, kidneys, nerves, and blood vessels.

Many people with pre-diabetes also have untreated sleep apnea, which is common among overweight and obese individuals, The condition repeated episodes where their upper airway closes during sleep, disrupting sleep and temporarily lowering oxygen levels.

Apnea has been associated with an increased risk of cardiovascular diseases, such as hypertension and stroke, and may decrease their ability to regulate blood sugar levels.

For the study, the researchers tracked 39 middle-aged volunteers with pre-diabetes and sleep apnea. Two-thirds of them (26) were randomly assigned to two weeks of CPAP treatment. The other 13 received a pill containing no medicine to be taken 30 minutes before bedtime.

After two weeks, blood sugar control improved for those in the CPAP group compared to the oral placebo group. In addition, the CPAP users had better regulation of insulin, lower levels of the stress hormone, norepinephrine, and lower blood pressure.

"Despite the demonstrated efficacy of lifestyle interventions and the availability of many drug treatments, the economic and public health burden of diabetes remains enormous," said Esra Tasali, M.D., assistant professor of medicine at the University of Chicago and senior author of the study.

"Assessment of sleep apnea should be considered in patients at high risk for diabetes and cardiovascular disease, since our study shows that treatment of sleep apnea can reduce these risks."