LONDON — Getting less than five hours of sleep at night raises an older person’s risk of premature death by a quarter, according to new research. The study finds middle-aged and older adults are 40 percent more likely to develop at least two life-threatening illnesses such as heart disease, cancer, and diabetes if they don’t get enough rest.
“Multimorbidity is on the rise in high income countries and more than half of older adults now have at least two chronic diseases. This is proving to be a major challenge for public health, as multimorbidity is associated with high healthcare service use, hospitalizations and disability,” says lead author Dr. Severine Sabia from University College London in a media release.
“As people get older, their sleep habits and sleep structure change. However, it is recommended to sleep for 7 to 8 hours a night – as sleep durations above or below this have previously been associated with individual chronic diseases,” Dr. Sabia continues. “Our findings show that short sleep duration is also associated with multimorbidity.”
“To ensure a better night’s sleep, it is important to promote good sleep hygiene, such as making sure the bedroom is quiet, dark and a comfortable temperature before sleeping. It’s also advised to remove electronic devices and avoid large meals before bedtime. Physical activity and exposure to light during the day might also promote good sleep.”
The findings are based on health data from 7,864 people over 50 in the United Kingdom. Scientists tracked the men and women, members of the Whitehall II study, for 25 years.
How much damage does less sleep do?
Previous studies reveal that blue light from smartphones and tablets fools the brain into thinking it’s daytime — blocking a sleep hormone called melatonin that is a potent antioxidant. Late night snacking can lead to obesity by reducing metabolism and increasing fat storage.
Dr. Sabia and colleagues compared the impact of self-reported sleep duration on each participant. They examined the relationship with mortality and whether each person had been diagnosed with two or more chronic diseases. At age 60, those who slept five hours or less a night were 32 percent more likely to have multimorbidity than peers who managed to get seven hours of rest. The risk rose to 40 percent at age 70.
Shorter slumber also increased the risk of one serious condition by 20 percent. Participants reporting poor sleep also displayed a 25-percent higher risk of death during the study period. There was no clear association between sleeping more than nine hours a night and multimorbidity in healthy individuals. However, there was a 35-percent higher risk of developing another illness among those who had already been diagnosed with a chronic condition.
This may be due to underlying health problems affecting sleep. Living with multiple chronic conditions is common with increases in life expectancy. The study in PLoS Medicine supports the promotion of good sleep hygiene in middle and old age.
Sleep is vital for healing the body
It is one of the first studies to connect poor sleep with multimorbidity — the co-occurrence of two or more chronic conditions.
“Getting enough sleep allows your body to rest. There are a host of other ways that poor sleep could increase the risk of heart disease or stroke, including by increasing inflammation and increasing blood pressure,” explains Jo Whitmore, senior cardiac nurse at the British Heart Foundation. “This research adds to a growing body of research that highlights the importance of getting a good night’s sleep.”
Prior studies show that the body heals and repairs damaged tissues during sleep, including the heart and blood vessels. Not getting enough sleep has been linked to every life-threatening illness, including Alzheimer’s.
The Whitehall II study was established in 1985 to investigate the causes of social inequalities in health.
South West News Service writer Mark Waghorn contributed to this report.