By Lois M. Collins
Deseret Morning News
Thousands of patients with fatigue are treated for depression and high blood pressure, but sleep apnea may be an underlying cause that’s completely ignored and undiagnosed.
That’s the conclusion of a large study conducted by researchers at LDS Hospital’s Intermountain Sleep Disorders Clinic, published this week in CHEST, the cardiopulmonary and critical care journal of the American College of Chest Physicians.
Sleep apnea is a serious sleep disorder that affects as many as 10 percent of Americans. It’s characterized by loud snoring and pauses in breathing during sleep. The diagnosis is reportedly missed in an estimated 82 percent of men and 93 percent of women with moderate to severe obstructive sleep apnea.
The study indicates that many physicians are treating obvious symptoms but not treating a condition that may be either the cause or a co-existing factor for the symptoms, said Dr. Robert J. Farney, director of the Intermountain Sleep Disorders Clinic and lead investigator of the study.
Hypertension and chronic fatigue are possibly the most common conditions for which patients seek medical attention, he said, and they are integral aspects of sleep apnea.
The lack of treatment for the underlying condition is a serious shortcoming, since sleep apnea is easy to diagnose and is very treatable, he said. It’s caused by negative airway pressure during sleep. The negative pressure doesn’t keep the throat open well. The most common treatment is use of nasal CPAP (continuous positive airway pressure), delivered through a mask during sleep. Treatment may include surgery, and weight loss is an important treatment, as well. There are factors that make the condition worse, from sleeping on the back to nasal congestion and drinking alcohol.
Known symptoms of sleep apnea are tiredness, high blood pressure and stroke. It has been proven to be a significant factor in nocturia, where someone gets up several times a night to go to the bathroom. And there is likely some link between sleep apnea and diabetes or insulin resistance, Farney said, especially in people who are mildly obese. Recent research at the clinic indicates that someone who has sleep apnea may have increased insulin resistance and, conversely, some of the problems created by diabetes may cause sleep apnea.
Earlier research at the clinic also showed a significant link between obstructive sleep apnea and left ventricular hypertrophy, a very dangerous heart condition that may affect 25 million Americans.
Treating obstructive sleep apnea has no downside. “It’s one of the few things I can do in medicine that can completely reverse a condition that has huge risks and problems without any adverse effects,” Farney said. “How many things can I do in medicine that have no chance of hurting someone? And it has significant impact on quality of life and other health complications.”
With all that’s known about sleep apnea, he said, it’s a condition that’s often overlooked when patients present their symptoms to their doctor. A psychiatrist, for instance, might think first of depression, while an endocrinologist might consider a thyroid or other metabolic problem.
The study indicated that among the 200,000 patients whose records were combed, those receiving medications for both depression and high blood pressure were 18 times more likely to eventually be diagnosed with sleep apnea — which Farney called a “staggering odds ratio.” The finding held true regardless of the patient’s age.
“Sleep apnea is more common as you get older,” Farney said, so it’s increasingly “difficult to disentangle from other variables.”
Other members of the research team were Alejandro Lujo, Robert L. Jensen, James M. Walker and Dr. Tom Cloward.
Source: www.deseretnews.com. © 2004 Deseret News Publishing Company.