Relationship Between Sleep Apnea and Cancer Risk in Women
Women with severe sleep apnea appear to also have an elevated risk of developing cancer, according to findings from a study by Pataka et al in the European Respiratory Journal. No causal relationship was demonstrated, but a link between nocturnal hypoxia in women and higher cancer risk was established.
“It’s reasonable to assume that sleep apnea is a risk factor for cancer, or that both conditions have common risk factors, such as overweight. On the other hand, it is less likely that cancer leads to sleep apnea,” noted senior author Ludger Grote, MD, PhD.
Previous studies have shown that, more often than others, people with sleep apnea have a cancer diagnosis in their medical history. The research is based on analyses of registry data collected in the European database ESADA on a total of some 20,000 adult patients with obstructive sleep apnea. About 2% of them also had a cancer diagnosis.
Study Findings
Advanced age was associated with elevated cancer risk, but adjusting the data for age, gender, body mass index, smoking, and alcohol consumption nevertheless showed a possible link between intermittent hypoxia at night and higher cancer prevalence. The connection applied mainly to women and was weaker in men.
“Our results indicate a cancer risk that’s elevated two- to three-fold among women with pronounced sleep apnea. It’s impossible to say for sure what causes underlie the association between sleep apnea and cancer, but the indication means we need to study it in more depth,” said Dr. Grote. “The condition of sleep apnea is well known to the general public and associated with snoring, daytime fatigue, and elevated risk of cardiovascular disease, especially in men. Our research paves the way for a new view—that sleep apnea may possibly be connected with increased cancer risk, especially in women.”
“Above all, the focus has been on the connection with one form of cancer: malignant melanoma. [Breast or endometrial cancer] may now become a new area. There may be a combined effect of female sex hormones and stress activation, induced by nocturnal hypoxia in sleep apnea, that can trigger cancer development or a weakening of the body’s immune system,” concluded the researchers.
Disclosure: For full disclosures of the study authors, visit erj.ersjournals.com.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
