Middle-aged people who regularly sleep six hours or less each night are more likely to develop dementia than those who sleep seven hours, according to a large study by British and French scientists.
Researchers found a 30 percent higher risk of dementia in those who had a consistently short night’s sleep in their 50s, 60s, and 70s, regardless of other risk factors such as heart and metabolic disease and poor mental health.
However, the study does not prove that too little sleep causes illness, as sleep loss itself can be one of the earliest symptoms of dementia. But some scientists believe the study’s results support the findings that persistent poor sleep may at least contribute to neurodegenerative disease.
8 THOUSAND PEOPLE WERE FOLLOWED FOR 25 YEARS
Dr Séverine Sabia, author of the study from the University of Paris, said: “I cannot tell you that sleep time is a major cause of dementia, but it can contribute to its development.”
Within the scope of the study published in the scientific journal Nature Communications, Sabia and her colleagues analyzed the survey data of the Whitehall II study, which was initiated at London College University in 1985 and tracks the health and lifestyles of more than 10,000 British volunteers. The French team focused on about 8,000 participants who reported their sleep patterns.
CREATED MORE THAN 30 PERCENT RISKS
During the 25-year follow-up period, 521 participants developed dementia and most were diagnosed in their late 70s. As a result of their analysis, scientists explained that those in their 50s and 60s who routinely sleep six hours or less each night are 30 percent more likely to develop dementia than those who typically sleep seven hours.
IT OCCURS IN ONE OF EVERY 14 PEOPLE OVER 65 YEARS
On the other hand, while smoking, drinking and obesity are risk factors for dementia, the chances of getting the disease suddenly increase with age. Dementia is estimated to affect one in 14 people over the age of 65 and one in six people over the age of 80. The risk of developing Alzheimer’s or vascular dementia doubles approximately every five years over the age of 65.
However, the first pathological changes that lead to dementia occur one to twenty years before the disease becomes apparent, with the accumulation of adhesive proteins called amyloid and tau in the brain. This process probably did not begin when the 1985 Whitehall II study first assessed the sleep of volunteers who later developed dementia. This means that if they get too little sleep, their insomnia is unlikely to be caused by brain changes associated with dementia.
Not participating in the study, a senior lecturer in dementia neurology at the University of Bristol, Dr. Liz Coulthard says, “This reinforces the evidence that poor mid-life sleep can cause or worsen dementia later in life. Taking measures to improve sleep, such as going outside during daylight hours, especially avoiding excessive alcohol or caffeine before going to bed, to help maintain natural rhythms that promote good sleep. It will be useful, “he said.
On the other hand, the findings came after an international research team reported that severely disrupted sleep could almost double women’s risk of dying from heart disease compared to the general female population. The study in the European Heart Journal found that the risk for men increased by about a quarter. While body mass index and sleep apnea, which disrupts breathing, contribute to “unconscious wakefulness”, it has been reported that by disrupting the body’s natural circadian rhythms, it can trigger fat accumulation in the arteries that can lead to cardiovascular problems.
ENDER Seen Giant Aneurism