Now, studies link snoring to cancer risk

Those With Severe Form Of Sleep Apnea Have 65% More Chances Of Developing Disease

 Two new studies have found that people with sleep apnea, a common disorder that causes snoring, fatigue and dangerous pauses in breathing at night, have a higher risk of cancer.

    The new research marks the first time that sleep apnea has been linked to cancer in humans. About 28 million Americans have some form of sleep apnea, though many cases go undiagnosed.

    For sleep doctors, the condition is a top concern because it deprives the body of oxygen at night and often coincides with cardiovascular disease, obesity and diabetes.

    “This is really big news,” said Joseph Golish, a professor of sleep medicine with the MetroHealth System in Cleveland who was not involved in the research.

    Golish, the former chief of sleep medicine at the Cleveland Clinic, said that the cancer link may not prove to be as strong as the well-documented relationship between sleep apnea and cardiovascular disease, “but until disproven, it would be one more reason to get your apnea treated or to get it diagnosed if you think you might have it”.

    In one of the new studies, researchers in Spain followed thousands of patients at sleep clinics and found that those with the most severe forms of sleep apnea had a 65% greater risk of developing cancer of any kind. The second study, of about 1,500 government workers in Wisconsin, showed that those with the most breathing abnormalities at night had five times the rate of dying from cancer as people without the sleep disorder. Both teams only looked at cancer diagnoses and outcomes in general, without focusing on any specific type of cancer.

    In both studies researchers ruled out the possibility that the usual risk factors for cancer, like age, smoking, alcohol use, physical activity and weight, could have played a role. The association between cancer and disordered breathing at night remained even after they adjusted these and other variables.

    Mitesh Borad, a cancer researcher and assistant professor of medicine at the Mayo Clinic who was not involved with the studies, called the findings “provocative” but said more research was needed to confirm the association.

    Recent animal studies have suggested that sleep apnea might play a role in cancer. When mice with tumors were placed in low-oxygen environments that simulate the effects of sleep apnea, their cancers progressed more rapidly. Scientist speculate that depriving mice of oxygen may cause their bodies to develop more blood vessels to compensate, an effect that could act as a kind of fertilizer for cancer tissue and cause tumors to grow and spread more quickly. Researchers wondered whether a similar relationship might exist in humans.