Patients with Type II diabetes have a far greater incidence of sleep apnea, a condition in which breathing stops periodically during sleep, than healthy people do. In fact, studies have shown that the severity of diabetes correlates to the severity of sleep apnea. This has led researchers to suspect a relationship between the two conditions. Doctors from several Chicago-area medical centers wondered whether treating sleep apnea in diabetic patients could improve both disorders.

What the researchers wanted to know: Can a conventional treatment for sleep apnea also lessen the severity of diabetes?

What they did: The researchers evaluated 25 individuals with controlled Type II diabetes who had been referred to a clinic because of sleep apnea. They kept a food diary and had their glucose monitored with a sensor beneath the skin for three days. (Excessive blood glucose is the No. 1 indication of diabetes.) Then the monitor was removed, and the patients underwent sleep apnea treatment using a continuous positive airway pressure (CPAP) device. Patients wear a mask that gently pushes a constant stream of air through the nose during sleep. After about three months, the patients again kept a food diary for three days while their blood glucose was monitored.

What they found: The sleep apnea treatment reduced blood glucose levels, especially in patients who used the CPAP apparatus more than four hours a night. After meals, when glucose levels usually peak, the levels dipped from an average of about 195 milligrams per deciliter to 135 mg/dL. (A reading of 200 mg/dL or above automatically defines a diabetic condition; anything below 180 mg/dL is considered safe for diabetics.) In addition, for the group as a whole, the number of times that individual glucose readings registered above 200 mg/dL decreased after CPAP therapy.

What it means to you: If you are a diabetic with sleep apnea, you might be able to address both by treating one. While CPAP does not replace careful monitoring of blood sugar levels, lifestyle changes, and medication, it could greatly help patients with sleep apnea and diabetes manage both conditions more easily.

Caveats: The number of participants was very small, and all were treated. There was no control group of individuals who received no treatment for comparative purposes.

Find out more: The National Diabetes Information Clearing House has information on all aspects of the disease, from how it is diagnosed to how it should be treated.

The American Diabetes Association also has general information about the disease, including on lifestyle changes you can make to help manage your disease.

Read the article: Babu, A.R. et al. "Type 2 Diabetes, Glycemic Control, and Continuous Positive Airway Pressure in Obstructive Sleep Apnea." Archives of Internal Medicine. Feb. 28, 2005, Vol. 165, No. 4, pp. 447–452.

Abstract online: http://archinte.ama-assn.org