July 3, 2012

Sleep Apnea Causing Cancer?

By: Erika Dunayer, Ivanhoe Health Correspondent

(Ivanhoe Newswire) -- Tossing and turning all night? Waking up yawning and feeling like a zombie? 18 million Americans who suffer from sleep apnea can relate. Now, two new studies are attempting to prove the condition leaving you weary could also cause cancer.

Sleep apnea is an interruption of breathing while you sleep. There are different levels of severity within this disorder. Sleep apnea is such a prevalent issue today because 80-percent of the people with this disorder are left undiagnosed. Dr. Michael Breus, PhD., a Clinical Psychologist and a Diplomat of the American Board of Sleep Medicine, told Ivanhoe that nearly half of his patients don't even know they have the condition or that it could cause such serious repercussions.

"What I really want to let people out there know is that if you don't treat your sleep apnea, bad things can happen," Dr. Breus of the American Board of Sleep Medicine told Ivanhoe.

Now, two studies are the first to show any connection between cancer and sleep apnea in humans. The results of these studies were both presented recently at the American Thoracic Society conference in San Francisco, California in May.

The first study, conducted at the University of Wisconsin School of Public Heath and Medicine, complied 22 years of data on sleep health for 1,522 men and women including periodic overnight sleep analysis using polysomnography, a measurement of sleep and breathing. There are several other factors that could affect cancer risk, including age, gender, weight, and smoking. Among the participants in the study, researchers found the presence of mild sleep apnea was associated with a 10 percent increase in death from cancer. Moderate sleep apnea was associated with a doubling of the risk of cancer death. Severe sleep apnea was associated with a nearly five-fold increase in death from cancer.

Another study from the University of Barcelona investigated the link between OSA (obstructive sleep apnea) and cancer in mice. They found that when mice with melanoma were deprived of oxygen periodically, their melanoma tumors grew more quickly than mice that were not deprived of oxygen. This kind of periodic oxygen deprivation is known as hypoxia. Hypoxia is the fundamental characteristic of obstructive sleep apnea. When a person has OSA, their airway collapses during sleep which deprives the body of oxygen for a short period of time, breathing is interrupted, and the levels of oxygen in the blood drop. The severity of sleep apnea is determined by how frequently these periods of interrupted breathing occur.

"A lot of the thoughts behind these studies had to do with oxygen deprivation. When you stop breathing, oxygen gets down your blood stream and then your cells freak out.

When your cells freak out, they can multiply which can be a variant of cancer," Dr. Breus said.
These studies also contribute to the growing body of knowledge that sleep apnea, left untreated, is dangerous and damaging to health. Before this latest cancer news, sleep apnea was already associated with several serious health problems, including stroke, heart disease, and diabetes.

"The most important thing is, if you are lying next to a bed partner and you hear them stop breathing, tell them. Because the sooner they tell their doctor, the better," Dr. Breus said.

Source: Interview with Dr. Michael Breus--The Sleep Doctor and thesleepdoctor.com, July 2, 2012