Sleep is healing: Getting fewer than 6 hours of sleep if you have chronic illness increases risk of cancer, early death

  Sleep is an important component of good health. It promotes healing and prepares the body for the next day, among other functions. That said, there are adverse consequences to lack of sleep, and a recent study shows just how grave they can be.

A group of researchers from Pennsylvania State University found that people with diabetes, high blood pressure or cardiovascular disease may be exposing themselves to an increased risk of early death and cancer by not getting enough sleep. The team suggests that sleeping for at least six hours is important to prevent adverse health outcomes, especially in the presence of existing illnesses.

“Our study suggests that achieving normal sleep may be protective for some people with these health conditions and risks,” said lead author Julio Fernandez-Mendoza, a sleep psychologist and an associate professor at the Pennsylvania State College of Medicine.

The findings of the study were published in the Journal of the American Heart Association.

Adverse effects of inadequate sleep on patients

The researchers examined the Penn State Adult Cohort, a general random population of more than 1,600 adults between 20 to 74 years old. The cohort was divided into two groups: one with stage 2 high blood pressure or Type 2 diabetes and another with heart disease or stroke. The participants were placed in a sleep laboratory for one night from 1991 to 1998. Then, the researchers tracked them until the end of 2016.

More than five hundred participants passed away in the entire duration of the study. The team looked at their records and came up with the following findings:

• One-third of the fatalities died due to heart disease or stroke, while one-fourth died due to cancer.
• People who had heart disease or stroke and slept for less than six hours had three times higher risk of dying from cancer.
• People who had high blood pressure or diabetes and slept for less than six hours had two times higher risk of dying from heart disease or stroke.

The researchers said that a shorter sleep duration should be considered as one of the risk factors used by primary and specialized care clinicians to determine the long-term outcomes of patients, particularly those with diabetes, high blood pressure or cardiovascular disease.

“I’d like to see policy changes so that sleep consultations and sleep studies become a more integral part of our healthcare systems,” said Fernandez-Mendoza. He added that identifying people with specific sleep issues may help researchers come up with improved prevention and treatment approaches.  

Getting enough sleep for a longer and healthier life

The following studies also show the importance of sleep for a longer and healthier life.

One study, published in the journal Sleep, suggested that sleeping for less than six hours at night may lead to an early death. Researchers examined data from 16 separate studies across Europe, the U.S. and Asia, which had a total of 1.3 million participants.

They found that those who slept for less than six hours are 12 percent more likely to die at an early age than those who slept for six to eight hours. Oversleeping also posed an adverse effect, as participants who had consistently gotten more than nine hours of sleep displayed an increased risk of premature death.

Another study, published in the International Journal of Cancer, found higher rates of breast cancer among women who work irregular hours. Researchers looked at the records of more than 1,300 healthy women and 1,200 women who had breast cancer. They found that the rate of the disease was 30 percent higher in those who worked irregular shifts, especially those who had this work schedule for a long time.

While most people are aware that lack of sleep is not good for health, its more serious consequences remain largely obscure. These studies serve as a reminder that regularly skipping hours of sleep can be life-threatening.