By Erin R. King

Aug. 10 (CBSHealthWatch)--Some people who feel fatigued or have a lack of energy during the day might not get as good a night's sleep as they think they do.

The problem could be obstructive sleep apnea, and it may not be diagnosed as often as it occurs because of the way people describe their symptoms, and how doctors interpret them, according to one expert.

"Patients with obstructive sleep apnea often use terms other than 'sleepiness' to describe important symptoms. In particular, they often choose 'fatigue,' 'tiredness' or 'lack of energy' to express their main problems, and that's in contrast to what we're traditionally taught--that obstructive sleep apnea causes sleepiness," says Dr. Ronald D. Chervin, assistant professor of neurology at the University of Michigan Health System and director of the university's sleep disorders laboratory.

Obstructive sleep apnea occurs when the throat closes periodically during sleep, causing the sleeper to stop breathing temporarily. This can occur up to hundreds of times each night without the person waking up. Other sleep disorders may also affect the breathing.

Chervin asked 190 patients diagnosed with obstructive sleep apnea about their symptoms. Lack of energy was their number one complaint.

"When we compared the other symptoms, tiredness and fatigue were just as popular as major problems as was sleepiness," Chervin says. "When they're forced to choose, about 40 percent of patients chose lack of energy as their biggest problem. Somewhere around 20 percent chose each of the others."

Sleep apnea is common, he says, citing a recent study that reported that as many as 24% of men and 9% of women may have breathing problems suggestive of the disorder.

The majority of these people are undiagnosed, Chervin says, which may have to do with a communication gap. He suspects that often, when a doctor not specifically trained in sleep disorders hears that a patient is fatigued, their first reaction may be to look for a medical cause like depression or a thyroid disorder.

Chervin says that it's important for doctors and patients not to dismiss the possibility of sleep apnea simply because the patient isn't stressing their "sleepiness."

Dr. June M. Fry, director of the Center for Sleep Medicine in Philadelphia, agrees. She says Chervin's study may help doctors think more about sleep disorders when talking to fatigued patients.

"I'm hoping that this paper will raise their awareness that these other terms that patients use could indeed be a signal that means they have a sleep disorder," Fry says.

If patients who simply complain of fatigue are asked a battery of questions about their sleep habits and problems, rather than just "Are you sleepy?" doctors can often uncover a possible sleep disorder, Fry says.

"I think that we need to pay attention to all of these terms," she says.

Both Fry and Chervin say that some patients may even be in denial about having daytime sleepiness and are reluctant to admit it, even to a doctor, because they fear it will affect their work or personal lives.

　　(From AOL.com)