Tuesday June 10 2:00 PM EDT

-- Approximately 30 million adult Americans have moderate to serious sleep disorders, yet only 5% are diagnosed and treated, a panel of experts said at a recent briefing in New York.

The most common causes of these disorders, grouped in the broad category of "excessive daytime sleepiness," include circadian rhythm disorder, sleep apnea, restless legs syndrome, and narcolepsy. All these disorders are "identifiable, diagnosable and treatable," said Dr. Thomas Roth, director of the Sleep Disorders Center at Henry Ford Hospital in Detroit.

Roth noted that unpublished data from a recent study conducted by Henry Ford Hospital researchers suggest that, in the past year, 5% of Americans have taken pharmacologic measures to combat sleepiness. Of these, 90% took over-the-counter (OTC) products.

"If they're taking a caffeine pill because they're on the road and feeling sleepy and need another half hour of wakefulness to get to their destination, that's good," he told the audience. "If they're taking pills to get through the day, it's not so good." Self-medication could mask an underlying medical condition, Roth said in response to a Reuters Health query, "but right now, we just don't know the scope of the problem."

Results of a recent Gallup survey conducted on behalf of the National Sleep Foundation were also announced at the briefing. Among the findings: 32% of adults scored 10 or higher -- indicating moderately severe sleepiness -- on the Epworth Sleepiness Scale, a short, validated test that tells people if they tend to fall asleep in situations when they normally should be awake. Close to half of those scoring 10 or higher said that daytime sleepiness interfered with routine daily activities, including work, parenting, and their ability to drive.

The latter problem has "serious public health consequences," observed Dr. Michael J. Thorpy, director of the Sleep-Wake Disorders Center at Montefiore Medical Center in the Bronx, New York. "Fall-asleep crashes tend to be deadlier than other crashes, and account for at least 100,000 police-reported crashes and 1,500 fatalities a year in the U.S. Moreover, sleepiness contributes to inattention, which accounts for one-sixth of all accidents."

"When a physician hears a complaint of excessive sleepiness, he should take it for real and do a complete physical examination. This is not a frivolous complaint," Dr. Joyce Walsleben, director of the New York University Medical Center Sleep Disorders Center told Reuters Health. Treatment varies depending upon the suspected cause, she said.

Sleep apnea is typically treated with breathing devices or surgery; restless legs syndrome with behavioral measures and applications of heat and cold; periodic, and rhythmic leg movements with levodopa/bromocriptine. Patients with narcolepsy -- a condition where a patient suddenly feels an uncontrollable need for sleep -- are often prescribed stimulants; and circadian rhythm disorders can respond to lifestyle changes.

A differential diagnosis is important, Walsleben continued, because, for example, "a severe sleep apnea can look like narcolepsy. It's easy to make a mistake." She suggests monitoring a patient for one month after making a diagnosis and prescribing therapy. If excessive daytime sleepiness persists, then refer the patient to a sleep disorder specialist, she advised.

"It would be wonderful if physicians would routinely ask about sleepiness or give the Epworth Sleepiness Scale," she added. The Gallup survey revealed that only 17% of those who have experienced daytime sleepiness severe enough to interfere with daily activities have consulted a doctor for the problem.

A copy of the Epworth Sleepiness Scale and educational materials on sleep disorders are available by calling 1-888-41-AWAKE, at the National Sleep Foundation Web site (http://www.sleepfoundation.org) and at the excessive daytime sleepiness site (http://www.daytimesleep.org).