Understanding the link between sleep and Alzheimer’s disease

Over 55 million people in the world live with dementia.

Alzheimer’s disease, the commonest cause of dementia, is slowly progressive, with changes in the brain long before symptoms appear. Early treatment can help people with Alzheimer’s retain their independence and quality of life.

Studies have shown that poor sleep can increase the risk of Alzheimer’s. Disturbances to the phase of sleep called slow-wave sleep, or deep sleep, may be particularly linked to Alzheimer’s.

It may be possible to treat Alzheimer’s by improving slow-wave sleep, but first we need to understand how slow-wave sleep and Alzheimer’s are linked.

Project aims

We plan to perform a large study to find out how altering slow-wave sleep affects people with early-stage Alzheimer’s disease.

People taking part in the study will be randomly assigned to one of 4 groups:

• Treatment with trazodone, a medicine that increases the length of the slow-wave sleep phase
• Treatment with zolpidem, a medicine that increases the time spent asleep, but not the length of the slow-wave sleep phase
• Treatment using noise delivered during slow-wave sleep, a technique called phase-targeted auditory stimulation, which increases the intensity of slow-wave sleep without increasing the total time spent asleep
• Fake treatment with a mock phase-targeted auditory stimulation device and mock tablet

We will use several techniques to study the effects of modifying participants’ sleep:

• Sleep recording
• Blood testing for signs of disease
• MRI scanning
• Recording the brain’s electrical activity
• Memory tasks

What we hope to achieve

We hope our project will lead to future studies of ways to improve slow-wave sleep, to slow the progression of Alzheimer’s disease.