‘Morning people’ linked with higher Alzheimer’s risk

19 August 2020

Researchers in the UK have linked sleeping patterns with an increased risk of dementia in people with a higher genetic risk of the condition. The scientific journal Neurology published the findings today (Wednesday 19 August).

The study was supported by the UK Dementia Research Institute, the country’s largest dementia research initiative, which is partly funded by Alzheimer’s Research UK.

What did the researchers look at?

The scientists studied the relationship between different sleep patterns, depressive disorder and Alzheimer’s disease.

They used different genetic studies collected from databases that included over 20,000 people diagnosed with Alzheimer’s disease.

Researchers analysed the genetic information using a research technique that can find out if there is cause and effect.

What did the researchers find?

Researchers found no evidence that different sleep patterns caused Alzheimer’s disease. They also found no evidence of cause and effect between major depressive disorder and Alzheimer’s.

They did find a small link between people at increased genetic risk for Alzheimer’s disease who were one percent more likely to call themselves “morning people” compared to people at lower genetic risk.

 Alzheimer’s Research UK’s expert opinion

Sara comments on morning sleep and dementiaDr Sara Imarisio, Head of Research at Alzheimer’s Research UK, said:
“Many of us have experienced a bad night’s sleep and probably know that it can have an impact on our memory and thinking in the short term, but an intriguing question is whether sleep problems have a long-term effect on the brain.

“This research shows a small link between different sleep patterns and the risk of developing Alzheimer’s disease, but did not find any evidence for sleep disturbance causing the disease.

“A recent large-scale review of risk factors for dementia within our control to change found there have not been enough studies in this area for sleep to be included on the list.

“Dementia is not an inevitable part of ageing and more evidence on the complex topic of sleep is needed before we can make a judgement on its impact on dementia risk. We hope findings like this will act as a catalyst for further research.”

Where to find the science paper?

Neurology: Sleep, major depressive disorder and Alzheimer’s disease: a Mendelian randomisation study