SLEEP LINK TO DEMENTIA RISK
New study suggests good night’s rest can keep disease at bay
A GOOD night’s sleep could be key to keeping dementia at bay.
Spending just 1 per cent less time in the dreaming stage has been linked to an increase in the risk of developing the condition, say researchers.
experts now believe improving sleep quality could be an important factor in preventing the disease, while problems with sleep could show a person is at risk.
Last night dr James Pickett, head of research at the Alzheimer’s Society, said: ‘There is increasing evidence that disturbed sleep is a risk factor for dementia.
‘There are things we can all do to try to improve our sleep, such as avoiding alcohol, caffeine and smoking in the hours before bed and trying to establish more routine around bedtime.’
it is thought rapid eye movement (ReM) sleep, otherwise known as the dream stage, boosts connections in the brain, helping to protect it against the onset of the disease.
A lack of ReM sleep could also be a sign of stress, which causes people to be more easily disturbed at night and is linked to dementia. Humans can experience several ReM sleep cycles through the night, during which
dreaming occurs, the eyes move rapidly and brain activity increases.
People also experience a higher body temperature, quicker pulse and faster breathing.
Dr Matthew Pase, co-author of the latest study by Boston University School of Medicine, said: ‘We have known for some time that REM sleep is reduced in persons with dementia, and some people thought that lower REM was caused by dementia.
‘Our findings are important because we show that lower REM sleep predicts the risk of dementia occurring in the future.
‘The next step will be to determine why lower sleep predicts a greater risk of dementia. By clarifying the role of sleep in the onset of dementia, the hope is to identify possible ways to intervene so that dementia can be delayed or even prevented.’
For the study, researchers at Boston monitored the sleeping patterns of 321 people over the age of 60 then followed them for up to 19 years to see if they developed dementia.
In total, 32 participants got dementia and 24 of these had Alzheimer’s disease.
The academics found people who did not develop dementia were in REM sleep for around 20 per cent of their sleeping time, on average, while those who did later develop the disease were in REM sleep for only 17 per cent of their sleep.
For every percentage reduction in the amount of time spent in REM, participants were 9 per cent more likely to suffer dementia of any kind and 8 per cent more likely to get Alzheimer’s.
Other stages of sleep were not linked with an increased risk of the disease.
Authors of the survey, published in the online journal Neurology, said it did not show cause and effect, so it was not possible to confirm whether a lack of REM sleep was causing dementia or if it was simply an early predictor of the disease.
Dr Pase said people could try to improve their overall quality of sleep in order to maximise the amount of time they spent in REM sleep.
This includes having a regular bedtime and wake-up time, sleeping in a dark, quiet room, avoiding caffeine before bed and limiting alcohol.
He warned that commercial fitness monitors, such as Fitbits and the Apple watch, do not differentiate between sleep stages, so people should not rely on these as a sign they are having enough REM sleep.
Last year the Scottish Government warned that dementia cases will soar, with nearly 20,000 people a year expected to be diagnosed by 2020.
The country’s ageing population means that more people every year will be at risk of developing the degenerative condition.
The warning came in a Holyrood report aimed at ensuring enough services are available to Alzheimer’s sufferers.
Campaigners said the figures were a ‘stark reminder’ that dementia should be a public health priority and called for more research.
In 2014, 16,712 people north of the Border were newly diagnosed with dementia.
By 2020, new diagnoses are set to increase by 17 per cent to 19,473, with most diagnoses among 80 to 84-year-olds.
Dementia usually affects those over 65 and is linked with brain decline, leading to memory loss and problems with understanding, thinking speed and judgment.
One in three people over 65 will develop the condition, which affects twice as many women as men. It can be caused by diseases such as Alzheimer’s or by strokes.
Earlier this year, Dr Pase and his colleagues found people who consistently sleep more than nine hours each night have double the risk of developing dementia within ten years, compared to those who sleep for nine hours or less.