Sleep is key to immune function and health, and a new study finds that may be especially true for patients battling melanoma.
The study found that severe, untreated cases of sleep apnoea – interruptions in nighttime breathing – are linked with more aggressive melanomas.
"This is the first large, prospective multicentre study that was specifically constructed to look at the relationship between sleep apnoea and a specific cancer," explained study author Dr Miguel Angel Martinez-Garcia, from La Fe University and Polytechnic Hospital in Valencia, Spain.
"While more research is needed, this study shows that patients in the study had markers of poor prognosis for their melanoma. It also highlights the importance of diagnosing and treating sleep apnoea," Martinez-Garcia said in a news release from the in a news release from the American Thoracic Society (ATS).
One expert said the finding isn't overly surprising. "Sleep deprivation can lead to immunologic dysfunction," noted Dr Jordan Josephson, a sleep apnoea specialist at Lenox Hill Hospital in New York City.
The findings were slated for presentation at the annual meeting of the ATS, in San Francisco.
The study involved 412 patients, averaging 55 years of age, all of whom had confirmed cases of cutaneous malignant melanoma. All of the patients were also studied to gauge how well they slept.
While it's impossible from this study to say that sleep apnoea causes melanoma to become more aggressive, the researchers found that apnoea was more common and severe for patients diagnosed with the most aggressive cancers.
This was true even when they factored out other risk factors for melanoma such as age, gender, weight, skin type and sun exposure, the research team noted.
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Experts who reviewed the findings said the results were preliminary but intriguing.
"One person dies every hour in this country from malignant melanoma," said Dr Doris Day, a skin cancer expert and spokeswoman for The American Society for Dermatologic Surgery.
Day believes that better sleep might help the body fight melanoma, since "many immunologic and restorative events take place during this time".
Another expert in sleep health agreed.
Sleep apnoea symptoms
"Although the mechanism of this effect is unclear, these results add to the growing list of adverse effects of obstructive sleep apnoea and point out the central role that sleep plays in health," said Dr Michael Weinstein, who directs the sleep disorders centre at Winthrop University Hospital in Mineola, New York.
Martinez-Garcia offered some advice to patients.
"People who snore, frequently wake up at night or have daytime sleepiness should see a sleep specialist, especially if they have other risk factors for cancer or already have cancer," he said.
"Physicians – especially dermatologists, cancer surgeons and medical oncologists – should ask their patients about potential sleep apnoea symptoms, and refer them for a sleep study if they have these symptoms," Martinez-Garcia added.
Experts note that findings presented at medical meetings are typically considered preliminary until published in a peer-reviewed journal.