Snoring might be more than a petty annoyance. Researchers from University of Wisconsin say that sleep-disordered breathing (SDB) or sleep apnea can lead to increased risk of cancer.

"Aside from being an annoyance to your spouse, family members and maybe even your neighbors depending on how loud your snoring is, sleep apnea is a severe problem. Drowsiness and sleepiness during the day increase the risk of accidents, and sleep apnea is associated with cardiovascular disease, heart disease, strokes, hypertension and cardiovascular mortality. Now, we see this new angle: an increase in cancer mortality," said Dr. F. Javier Nieto, lead author of the study.

The study was based on the analysis of a 22 year old data available on more than 1500 participants from Wisconsin Sleep Cohort.

The researchers found that people with SDB died from cancer at a rate of 4.8 percent than people who did not have any breathing problems.

"Clearly, there is a correlation, and we are a long way from proving that sleep apnea causes cancer or contributes to its growth. But animal studies have shown that the intermittent hypoxia (an inadequate supply of oxygen) that characterizes sleep apnea promotes angiogenesis—increased vascular growth--and tumor growth. Our results suggest that SDB is also associated with an increased risk of cancer mortality in humans,” said Nieto.

In a related study from Spanish Sleep Network, researchers found that people with disturbed breathing during sleep were up to 69 percent increased risk than people who did not have breathing problems at night. This study followed more than 5000 people over a period of 7 years to assess the risk of cancer in people with SDB, reports

The present study had focused on death rates due to cancer.

"In our large population-based sample, SDB was associated with an elevated risk of cancer mortality. Additional studies are needed to replicate these results. 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,” said Dr. Nieto.

According to a study by Centers of Disease Control and Prevention (CDC), almost half (48 percent of 74,571 study participants) reported snoring.