Sleep is the great healer. Get less than the recommended seven hours a night — or mess up your circadian clock through, say, night shift work — and you put yourself at risk for all kinds of health issues: high blood pressure, heart disease, diabetes, depression, obesity, lowered immunity and yes, even cancer.
Now, a new study by public health researchers at Fred Hutchinson Cancer Research Center suggests sleep isn’t just important for overall health — it may also improve your chances of breast cancer survival.
Epidemiologist and lead author Dr. Amanda Phipps, who presented her findings Wednesday at SLEEP 2015, the annual meeting of the Associated Professional Sleep Societies, found an association between women who died of breast cancer and poor sleep pre-diagnosis.
“The women who told us they slept less than five hours a night on average [before their diagnosis] had about a 1.5-fold increased risk of dying from their disease compared to women with breast cancer who said they slept the recommended seven to eight hours a night,” said Phipps, who used data from approximately 7,500 Women’s Health Initiative study participants diagnosed with breast cancer for her analysis. “And women who weren’t getting enough sleep and were snoring were about twice as likely to die from their disease.”
Phipps emphasized that the study did not look at sleep patterns after diagnosis, when many women regularly lose sleep due to stress and other factors.
“We were looking at general lifetime patterns,” she said. “We know that when a woman is diagnosed there’s a lot of stress and anxiety and treatment side effects, all of which have a bearing on sleep quality.”
Study co-author and sleep expert Dr. Nathaniel Watson, a professor of neurology at the University of Washington and president of the American Academy of Sleep Medicine, also noted that even though the women who died had “extreme sleep deprivation,” it was too early to say poor sleep before a cancer diagnosis was what directly led to their death.
“It’s an association,” he said. “You don’t have enough evidence to say that it’s a cause.”
Both researchers hoped the first-of-its-kind study would inspire further research in the area of sleep and cancer survival and motivate cancer survivors – and others -- to focus on good sleep habits in much the same way they focus on diet and exercise.
“[These results] could potentially be empowering,” Phipps said. “Sleep is certainly something that is controllable. We have control over it more than family history of the disease. These results generally suggest that the more attention we give to sleep as an important aspect of overall health, the better we might do for breast cancer patients. Sleep may be something we can encourage and promote to help women diagnosed with breast cancer to improve their overall health and to potentially improve their prognosis.”
Poor sleep is a common trend among breast cancer patients, according to Dr. Larissa Korde, a Fred Hutch clinical and public health researcher and breast cancer oncologist at Seattle Cancer Care Alliance.
But sleep deprivation is not just about the anxiety surrounding a cancer diagnosis. It’s a direct result of certain types of treatment.
“Women who’ve had chemotherapy will develop menopausal symptoms like hot flashes and night sweats and that affects sleep,” she said. “And hormone medications like tamoxifen and aromatase inhibitors also cause night sweats, which impact sleep.”
Most women are diagnosed with estrogen-receptor-positive (ER+) breast cancer, which is fueled by estrogen, and so in addition to traditional therapies like surgery, chemo and/or radiation, they often receive these types of estrogen-blocking drugs.
“When people are having a lot of difficulty with sleep, we’ll recommend trying something like melatonin, which can help,” Korde said. “And sometimes taking the AI [aromatase inhibitor] or tamoxifen at a different time is helpful. If they have a lot of night sweats, I recommend they take them first thing in the morning rather than before they go to bed at night.”
Korde said antidepressants and other medications can also curb treatment-related hot flashes (a recent Fred Hutch study found Effexor was particularly effective), but said breast cancer patients should always check with their oncologist before using these medications.
She also stressed that poor sleep isn’t necessarily a given for each and every breast cancer survivor.
“I think people do get relief as they get further down the line,” she said. “It varies from person to person but it’s not like, ‘This is it. Everybody has it.’ It’s an issue that we work through and women are able to get back to normal.”
Beth Gainer, a 54-year-old Chicago college professor and writer who was diagnosed with breast cancer in 2001, said she actually sleeps more now than she did pre-diagnosis.
“I was an insomniac for years before diagnosis and only got four to six hours of sleep,” she said. “It was easy for me to fall asleep but staying asleep was a challenge. Now I average about seven to eight hours a night. My sleep is much better post-treatment, although it’s far from ideal.”
Gainer said fear of recurrence does cause some sleeplessness but an anti-anxiety medication “helps me feel less haunted by my cancer experience and keeps my mind from wandering to dark places.”
Does the fact that she didn’t sleep well pre-diagnosis worry her?
“I really don't worry about poor prognosis and a lack of sleep,” she said. “I've known career insomniacs who have stayed healthy, and I've known good sleepers who have fallen ill. I do think, however, that my insomnia pre-diagnosis didn't help matters in terms of my own health. I do worry about my future health like so many who have had breast cancer, but I'm not worried that my past lack of sleep will cause me to fall ill in the future.”
How can breast cancer patients, survivors and others improve their sleep?
UW sleep expert Watson offered these tips:
Need additional advice? Click here for sleeping tips from Living Beyond Breast Cancer.
Diane Mapes is a staff writer at Fred Hutchinson Cancer Research Center. She has written extensively about health issues for NBC News, TODAY, CNN, MSN, Seattle Magazine and other publications. A breast cancer survivor, she also writes the breast cancer blog doublewhammied.com. Reach her at email@example.com.
Solid tumors, such as those of the breast, are the focus of Solid Tumor Translational Research, a network comprised of Fred Hutchinson Cancer Research Center, UW Medicine and Seattle Cancer Care Alliance. STTR is bridging laboratory sciences and patient care to provide the most precise treatment options for patients with solid tumor cancers.