In obstructive sleep apnea (OSA), the upper airway narrows or collapses during sleep, cutting off breathing. People with OSA may be aroused hundreds of times each night, just enough to start breathing again.

Usually the sleeper doesn't recall the partial waking episodes, but feels tired every day. If you have type 2 diabetes, especially if you're overweight, and you feel sluggish all the time, it may well be the fault of OSA.

Recently our Advisory Board member Daniel Einhorn, MD, tested 279 type 2 patients for OSA at the Whittier Institute for Diabetes. A full 36 percent of his patients had it. Men were twice as likely to have it as women, especially if they were over 62 years old.

If you have type 2 diabetes, Dr. Einhorn advises that you get yourself screened for OSA. Estimates are that up to ninety percent of people who have it remain undiagnosed. It's not something you want to live with, however, because it's associated with insulin resistance, higher A1c's, and a number of other dire long-term effects, including cardiovascular disease, hypertension, depression, sexual dysfunction, and even an increased risk of car crashes.

Conversely, treating OSA improves glucose metabolism and diabetes control. And a good night's sleep can have a salutary effect on your ability to stick with a healthy diet or exercise regimen.

The most effective non-surgical treatment for OSA is nasal continuous positive airway pressure (CPAP). A CPAP machine has a clear plastic mask worn over the nose and mouth, a lot like a diving mask, that forces air into the airway during sleep, thereby preventing the airway from collapsing. (It's a lot more comfortable than you might expect from the description. We tried one on at a recent diabetes conference, and it wasn't tight or uncomfortable at all.)

If you have type 2, especially if you're an overweight man, ask your doctor to test you for sleep apnea or consult one of the American Academy of Sleep Medicine's (AASM) accredited sleep facilities. For a listing of facilities in your area, go to www.SleepCenters.org.

Sources: Medline Plus; The Whittier Institute for Diabetes; American Academy of Sleep Medicine

Editor's Note: My brother went undiagnosed for sleep apnea and suffered all kinds of problems, including fibromyalgia, as a result. We were very relieved when he finally got a CPAP machine.