Sleep apnoea linked to Alzheimer’s

NEW YORK: Researchers have found a link between sleep apnoea and increased levels of a toxic brain protein commonly associated with Alzheimer’s disease.

The findings suggests that people suffering from sleep apnoea may have higher accumulations of an Alzheimer’s biomarker called tau in an area of the brain that helps with memory.

Those who had apnoeas had, on average, 4.5% higher levels of tau in the entorhinal cortex than those who did not have apnoeas, suggests the study presented at the American Academy of Neurology’s 71st annual meeting in Philadelphia.

Tau, a protein that forms into tangles, is found in the brains of people with Alzheimer’s disease.

“Our research results raise the possibility that sleep apnoea affects tau accumulation. But it is also possible that higher levels of tau in other regions may predispose a person to sleep apnoea,” said co-author Diego Z Carvalho of Minnesota’s Mayo Clinic.

Obstructive sleep apnoea involves frequent events of stopped breathing during sleep, although an apnoea may also be a single event of paused breathing during sleep.

“A person normally has fewer than five episodes of apnoea per hour during sleep,” Carvalho said.

For the study, the research team involved 288 people of age 65 and older who did not have cognitive impairment.

Bed partners were asked whether they had witnessed episodes of stopped breathing during sleep.

Participants had positron emission tomography brain scans to look for accumulation of tau tangles in the entorhinal cortex area of the brain, which helps manage memory, navigation and perception of time.

The researchers identified 43 participants, 15% of the group, whose partners witnessed apnoeas when they were sleeping. | IANS