Ask Dr Marie: Millions of Diabetics May Have Undiagnosed Sleep Apnea

Many obese patients with type 2 diabetes have a dangerous but treatable sleep condition called sleep apnea. Of 306 obese patients with diabetes who underwent a sleep study, 87 percent of them had sleep apnea but had never been previously diagnosed, according to a recent study published in the journal Diabetes Care,

This is a staggering number and suggests that both patients and doctors need to pay closer attention. Just imagine -- with more than 24 million people with type 2 diabetes, and most of them overweight or obese, there is a huge number of people who are undiagnosed and untreated for sleep apnea. Sleep apnea leads to a number of serious conditions including increased risk for heart attack, heart failure and even stroke.

In my experience, many people with diabetes don't even know they are at risk for sleep apnea, and have not been advised to have a sleep study to make the diagnosis. But the good news is that it is easily diagnosed with a sleep study and effectively treated with a special breathing machine at night called a continuous positive airway pressure (CPAP) machine. That may sound scary, but the newer models of breathing machines are portable, more comfortable and a lot quieter.

Another study from the U.K. found that more than half of all diabetic patients with sleep apnea have the serious form of eye disease called retinopathy, whereas less than one-third of diabetic patients without sleep apnea had retinopathy. So it seems that sleep apnea is linked to this serious but treatable eye condition as well.

These two studies on diabetics and sleep apnea hit close to home because one of my four sisters has sleep apnea -- and, yes, she is an obese type 2 diabetic.

I know she is checked regularly for retinopathy and to date has not developed the serious eye changes that need treatment. But many patients with diabetes fail to have their annual eye exam and thorough check of their retina.

In retrospect, I think my sister had sleep apnea for years before she was diagnosed and, finally, treated. She lives alone, so no one could alert her to abnormal breathing at night or snoring. And although she often had daytime drowsiness, she attributed this to her busy teaching schedule and simply failed to mention it to her physician. Since my sister has been treated with a CPAP machine, her energy has returned and she no longer falls asleep during the day. Her blood pressure is also now much easier to control.

Because of research findings such as these, it is my hope that more doctors will talk to their patients about the symptoms and signs of sleep apnea and recommend sleep studies to many more of their diabetic patients.

My advice: If you know someone who is overweight or obese with diabetes, ask them if they had a sleep study. And, while you are at it, ask them about the following, as well:

1) Hemoglobin A1c levels less than 7 percent;

2) Annual ophthalmologic exam by a specialist in diabetes;

3) Blood pressure under 130/80 (ask about taking an ACE inhibitor to lower blood pressure and prevent kidney disease);

4) LDL cholesterol under 100;

5) Triglycerides under 200 fasting;

6) A baby aspirin daily;

7) Annual test of kidneys with a special urine test for protein;

8) Annual check of feet including a test of nerve function;

9) An annual flu shot and the pneumonia vaccine;

10) Don't smoke (good advice for us all).

This may seem like a long list, and it is. But keeping these numbers in check and getting the necessary medical exams can make all the difference in preventing serious complications from diabetes.

Pay it forward -- help a friend with diabetes by being their health buddy, offer to go with them for important tests and help them to achieve their target medical goals.

As always, I welcome your comments and questions.

Dr. Marie Savard is an ABC News medical contributor. Her new book, "Ask Dr. Marie: Straight Talk and Reassuring Answers to Your Most Private Questions," will be available in August.