And so, to bed: the relationship between sleep and Alzheimer’s Disease

According to the World Health Organisation, around 50 million people have dementia worldwide, with Alzheimer’s Disease (AD) accounting for 60-70% of those cases. Around 10 million people are diagnosed with the condition each year, with the disease mainly affecting older people¹. It’s important to note dementia is not a normal or inevitable part of ageing. As you already know, there are lifestyle changes you can make now to decrease your risk of dementia. One of them is the amount of sleep you’re getting. 

Lack of sleep: a risk factor

Sleep has been identified as one of the many risk factors associated with AD, and according to studies the link between lack of sleep and AD is a two-way street². Epidemiological studies have shown that there is an inferred risk between AD and disrupted sleep during adult life³, while early research has found that the way in which sleep disruption and AD interact can influence the cause of the condition and also exacerbate it⁴. Insomnia and sleep apnea have also been discovered to be prominent in AD, but on their own also increase the risk of mild cognitive impairment⁵.  

Sleep, a waste removal system

A good night’s sleep is often something that can leave us feeling refreshed and rejuvenated, but did you know it’s also something that greatly contributes to the brain’s waste removal system? The glymphatic system, as it is called, helps reduce the build-up of proteins in the brain associated with AD. These proteins can build up in the areas of the brain responsible for deep sleep. If our sleep is disrupted these proteins build up, which can then in turn affect our ability to get deep sleep. The less we sleep the more these proteins accumulate and the more our ability to get deep sleep is affected, and the more our ability to remove these proteins is impaired⁶. It can become a vicious cycle and it’s this process which is at the core of much of the research that has uncovered a link between poor sleep and conditions such as AD.

What’s next? 

While sleep alone is not a ‘magic bullet’ against AD, there is enough evidence to suggest that ensuring you get enough sleep over your life span can lower the risk of AD⁷. The upside is that sleep is something that can be addressed and also modified according to an individual’s needs. For many of us, getting plenty of sleep at night could be one of the first steps to take in addressing the risk of dementia in later life.

Smart Change

The only person who really knows how lack of sleep affects you is you. So, take the time to focus on how you feel when you do not get a solid amount of sleep. By becoming more self-aware of the effects of sleep on your general health and wellbeing, the better placed you are to make the necessary changes to your lifestyle.‍

Read more about behaviours that can benefit sleep.