People who snore may have an increased risk of cancer, according to a new study.
Obstructive sleep apnea is a sleep disorder that affects millions of Americans each year; presenting as loud snoring, gasping and daytime sleepiness.
The symptoms are due to an obstruction of people’s airways when they sleep, resulting in stopping people from breathing throughout the night. Although annoying for those suffering it — and for those sharing living spaces — researchers think it could be an indication of cancer.
People who are overweight or obese, have diabetes, smoke or consume large amounts of alcohol are most at risk, according to the study, which was presented at a medical conference in Barcelona on Monday. The Swedish experts said snoring may have something to do with the lack of oxygen snorers get during the night.
In the United States, about 30 million people have sleep apnea, but only 6 million are diagnosed with the condition, according to the American Medical Association.
Data from 62,811 patients — five years before they started treatment for the disorder — in Sweden was looked at. It was found that people suffering from a severe case of the disorder were at greater risk of developing blood clots in their veins — a potentially life-threatening condition.
Dr. Andreas Palm, a researcher and senior consultant at Uppsala University, Sweden, said it’s known already that patients with OSA have an increased risk of cancer.
“But it has not been clear whether or not this is due to the OSA itself or to related risk factors for cancer, such as obesity, cardiometabolic disease and lifestyle factors,” he explained in the press release Monday. “Our findings show that oxygen deprivation due to OSA is independently associated with cancer.”
Researchers sorted patients into two groups. One cohort was 2,093 patients that had the disorder and were diagnosed with cancer before there was an OSA diagnosis. The control group had the disorder but no cancer, according to the study.
The study measured the number of breathing disturbances patients experienced when sleeping and scored them on the apnea hypopnea index (AHI).
They also looked at how many times oxygen levels in the blood fell by 3% for at least 10 seconds every hour — the oxygen desaturation index (ODI).
According to the results — with researchers also taking into account factors such as body size, other health problems and socioeconomic status — patients with cancer generally had more interruptions during their sleep and more severe OSA.
“[These patients] measured by an apnea hypopnea index average of 32 versus 30, and an oxygen desaturation index of 28 versus 26,” Palm said. “In further analysis of subgroups, ODI was higher in patients with lung cancer (38 versus 27) prostate cancer (28 versus 24) and malignant melanoma (32 versus 25).”
However, researchers said the study can’t show OSA causes cancer — only that it is associated with it — with lifestyle factors such as physical activity and food preferences not thoroughly accounted for in the study.
The research team plans more research with an increased number of patients and to follow them over time.
“The association between OSA and cancer is less well established than the link with diseases of the heart and blood vessels, insulin resistance, diabetes and fatty liver disease,” Palm said. “Therefore, more research is needed, and we hope our study will encourage other researchers to research this important topic.”