Colon cancer is now being added to the list of risk factors associated with inadequate sleep.
An inadequate amount of sleep has been associated with higher risks of obesity, heart disease, diabetes, and death. Now colon cancer can be added to the list.
In a new study published in the journal Cancer, researchers from University Hospitals (UH) Case Medical Center and Case Western Reserve University School of Medicine, found that individuals who averaged less than six hours of sleep at night had an almost 50% increase in the risk of colorectal adenomas compared with individuals sleeping at least seven hours per night.
“To our knowledge, this is the first study to report a significant association of sleep duration and colorectal adenomas,” said Li Li, MD, PhD, the study’s principal investigator, family medicine physician at UH Case Medical Center and associate professor at Case Western Reserve University School of Medicine. “A short amount of sleep can now be viewed as a new risk factor for the development of the development of colon cancer.”
In the study, patients were surveyed by phone prior to admitting to the hospital for scheduled colonoscopies at UH Case Medical Center. They were asked demographic information as well as questions from the Pittsburg Sleep Quality Index (PSQI), which obtains information about the patient’s overall sleep quality during the past month by asking how frequently one has trouble sleeping and how much sleep one has had per night.
Of the 1,240 patients, 338 were diagnosed with colorectal adenomas at their colonoscopy. The patients with adenomas were found in general to have reported sleeping less than six hours compared to compared to those patients without adenomas (control) patients, and the association between amount of sleep and adenomas remained even when adjusted for family history, smoking, and waist-to-hip ratio (a measurement of obesity).
The researchers also found a slightly stronger association of sleep duration with adenomas with women compared to men, but the difference was not statistically significant.
Li said the magnitude of the increase in risk due to less hours of sleep is comparable to the risk associated with having a first-degree relative (parent or sibling) with colon cancer, as well as with high, red meat intake.
“Short sleep duration is a public health hazard leading not only to obesity, diabetes and coronary heart disease, but also, as we now have shown in this study, colon adenomas,” he said. “Effective intervention to increase duration of sleep and improve quality of sleep could be an under-appreciated avenue for prevention of colorectal cancer.”
Although why fewer hours of sleep may lead to colon cancer is unknown, Li said some of theories include that less sleep may mean less production of melatonin, a natural hormone that in animals has been linked to DNA repair, or that insulin resistance may underlie the link between sleep disturbance and cancer development.
Source: University Hospitals