Disrupted sleep could increase the risk of dementia, studies suggest

Disrupted sleep could increase the risk of dementia, a series of major studies suggests.

Research on more than 1,600 people found that those suffering from disordered breathing at night were more likely to suffer an accumulation of proteins linked to Alzheimer’s disease.

The three US studies examined links between obstructive sleep apnoea - one of the most common sleep disorders - and changes to the brain which may indicate a greater risk of dementia.

Build up of amyloid proteins is known to be a precursor to diseases such as Alzheimer’s disease.

The first study of 516 healthy pensioners found that those with self reported disordered breathing had higher levels of amyloid proteins in the brain, and accumlated it a faster rate than those with more regular sleeping habits.  The second piece of research, tracking 798 people with mild memory problems, found a faster build up of the same protein among those with the sleep disruption.

The third, which tracked the same groups, and 325 people with Alzheimer’s disease, found similar changes, and a build up of another protein tau, in those suffering from sleep apnoea, a condition which around one in four poeple suffer from.

The condition occurs when the upper airway closes fully or partially, interrupting sleep repeatedly.

Researchers said it was possible that constant interruptions to deep sleep meant it was not possible for the brain to clear deposits of plaque, which would normally happen during the sleep process.

Studies on people repeatedly jolted awake during the night have also showed increases in amyloid buildup, they said.

Dr Carol Routledge, Director of Research at Alzheimer’s Research UK, said: “Conditions such as sleep disordered breathing can get in the way of a restful night’s sleep, and may have wider reaching health impacts.

“We know that Alzheimer’s proteins can start to build-up over a decade before symptoms appear so it is often difficult to tease apart cause and effect in the relationship between sleep problems and dementia.”  “Understanding how sleep disorders could affect our risk of dementia is of great importance, especially if managing these conditions could help to reduce the number of people developing dementia,” she said.