A team at the University of Wisconsin in the US found a strong association between sleep disordered breathing (SDB) and cancer death that increases with severity.
Snoring is one of the main symptoms of SDB, and the study claimed people with severe SDB were almost five times more likely to die of cancer than those without the problem.
SDB covers a range of disorders that lead to interrupted breathing during sleep. The most common is obstructive sleep apnoea, in which the airway collapses, leaving the sleeper struggling for breath and snore. It is linked with obesity, diabetes, high blood pressure, heart attacks and strokes.
The latest research also pointed to a connection with cancer mortality, the Daily Telegraph reported.
In the study, scientists looked at 22 years-worth of data on a total of 1,522 people who took part in a study of sleep problems. Study participants underwent tests that included measurements of sleep and breathing at four-year intervals.
The results, presented at the American Thoracic Society international conference in San Francisco, showed a link with cancer death that increased sharply with SDB severity.
People with mild SDB were just 0.1 times more likely to die from cancer than those without the problem. But moderate SDB doubled the chances of cancer death, while severe SDB increased the risk 4.8 times.
Study leader Dr Javier Nieto said: "The consistency of the evidence from the animal experiments and this new epidemiologic evidence in humans is highly compelling."
"In vitro (laboratory) and animal studies suggest that intermittent hypoxia promotes angiogenesis and tumour growth, which can explain these observations."
"Ours is the first study to show an association between SDB and an elevated risk of cancer mortality in a population based sample.
"If the relationship between SDB and cancer mortality is validated in further studies, the diagnosis and treatment of SDB in patients with cancer might be indicated to prolong survival," Dr Nieto said. (More)
