Sleep six hours or less linked to a higher dementia risk, study finds

The researchers found that 50-year-olds who slept six hours or less at night had a 22% higher risk of developing dementia later in life, even after checking with heart, metabolic and mental health issues. Sixty-year-olds were 37% more likely to develop the disease. The comparisons were with people who slept seven hours every night.

A group of European researchers looked at data from almost 8,000 adults in the UK for more than 25 years and linked the data to dementia diagnoses in electronic health records. The data comes from a study by British civil servants from University College London that began in 1985. Since then, participants are interviewed every four to five years.

Participants reported their sleep duration and some wore sleep detectors overnight to confirm that their self-report was accurate. While the authors warned that the findings may not determine whether less sleep causes dementia, they said the new study contributes to shorter-term research showing that too little sleep is linked to the development of the disease.

Other studies have shown that too little sleep and excessive sleep are associated with increased risks, but this particular study did not show a link between dementia and sleeping eight hours or more per night. Studies have also shown that interruptions that prevent people from getting a good night’s sleep are associated with a higher risk of dementia.

Previous research also suggests that obesity, high systolic blood pressure and mental health issues such as depression increase the risk of sleep problems and dementia.

“While we can not say that sleep duration has a causal effect on dementia, it would be good to encourage good sleep hygiene,” said Séverine Sabia, an epidemiologist at the French National Institute of Health and Medical Research, also known as Inserm, said. who is lead author of the study. She said turning off mobile devices 30 minutes before going to bed and developing an exercise routine can help people fall asleep more easily.

What sets this study apart from others is that it examines study subjects over a long period of time, said Rebecca Robbins, a sleep scientist at Brigham and Women’s Hospital in Boston, who was not involved in the study. Most studies published on sleep and dementia span 20 years or less, she said.

The adjustment for confusions such as depression was also an important feature of the study. “It gives us greater confidence that this study looked purely at the link between dementia and sleep,” she said.

She did note one limitation: the researchers relied on self-reported data for sleep duration, which people tend to overestimate, Drs. Robbins said. But they were able to reduce it by confirming some of the self-reported data using sleep trackers, she said.

Given the findings, dr. Robbins suggests that people try to get exposure to natural light during the day because it helps to adjust their circadian rhythm in their environment. She also recommends that you eat dinner at least an hour before bedtime, as digestion can make it harder to sleep.

About half an hour to an hour before she goes to bed, she suggests doing soothing things to get to bedtime.

‘You do not expose yourself to bright blue light, do not shower or bathe, light a candle, meditate. These little rituals can help a lot, ”she said.

Write to Sarah Toy by [email protected]