The Link Between Poor Quality Sleep And Alzheimer’s Disease

Studies have linked sleep disturbances earlier in life to the development of Alzheimer’s disease. That doesn’t mean your risk of developing dementia is definitely increased if you struggle to get a good night’s sleep; the research is still inconclusive. But developing a good sleep routine has numerous benefits for brain health¹.

Sleep supports your memory and concentration. It also helps to keep your moods stable and prevent depression and anxiety. When your sleep quality is poor and you struggle to fall asleep and stay asleep on a regular basis, you will find you struggle to pay attention and solve everyday problems. Memories are consolidated during sleep, so when you don’t get enough deep sleep, you may find yourself struggling with recalling information and events.

It is not a big leap for researchers to consider whether poor quality sleep increases your risk for dementia later in life, or if insomnia is an early sign of Alzheimer’s disease. Either way, there is a link between poor quality sleep and Alzheimer’s disease.

What happens to the brain when you have Alzheimer’s Disease?

Your brain is a hive of neurons that have been forming connections since before you were born. These specialised cells transmit information to each other in the brain, and to your muscles and organs via chemical and electrical pathways. For example, when you prick your finger on a thorn, neurons send a signal to your brain to let you know you have hurt yourself. The return message to your muscles tells you to remove your finger from the thorn.

The connections between the neurons are damaged, interrupting the communication pathways, resulting in cell death and loss of function². The five characteristics most commonly observed in the brain of someone with Alzheimer’s disease are:

1. Amyloid plaques: Beta-amyloid protein is formed from the breakdown of a larger protein. It occurs normally in the brain, but in Alzheimer’s disease, it clumps together to form plaques between the neurons, interrupting cell function.
2. Neurofibrillary tangles: Tau is a protein found in all neurons. In healthy nerve cells, tau binds to microtubules (the vessels for nutrients inside the cell body), to keep them stable. In Alzheimer’s disease, tau is detached from the microtubules and binds to other tau molecules, forming threads, which create tangles inside the neurons, blocking the cell’s transport system.
3. Chronic inflammation: Waste, toxins, and amyloid plaques are removed from a healthy brain by glial cells, especially microglia. In the Alzheimer’s brain, these substances build up causing chronic inflammation.
4. Vascular changes: Mini-strokes, the build-up of beta-amyloid deposits in the arteries in the brain, and hardening of the arteries are commonly found in the brains of people with Alzheimer’s disease. Vascular problems may be a cause and a consequence of dementia.
5. Loss of neuronal connections: As the connections between nerve cells are disrupted and neurons start to die, the brain begins to shrink.

Research reports a strong genetic link to Alzheimer’s disease. It is estimated 60% to 80% of cases are inherited³. The study of genomics and epigenetics informs us our environment has an influence on our gene expression.

Therefore, your lifestyle can change how your DNA determines your health. Factors such as diet, exercise, stress, and sleep may have an impact on whether or not you develop dementia in old age⁴.

The importance of sleep for health and well-being

No matter how old you are, sleep is important for optimal health. According to an American Academy of Sleep Medicine position statement⁵:

“Short-term sleep deprivation, long-term sleep restriction, circadian misalignment, and untreated sleep disorders can have a profound and detrimental impact on physical health, mental health, mood, and public safety. Chronic insufficient sleep is associated with an increased risk of mortality and contributes to both the individual risk and societal burden associated with several medical epidemics, including cardiovascular disease, diabetes, obesity, and cancer. Emerging data suggest that extending the nightly sleep duration of people who habitually get insufficient sleep is associated with health benefits.”

Sleep is essential for your survival. It allows your body to recover from your daily activities and repair tissue that’s been damaged. Sleep is involved in the following⁶:

• Development of neural pathways
• Learning
• Memory
• Mood regulation
• Heart health
• metabolic function
• Removal of toxic waste products from the body and the brain

Looking at this list, it is clear sleep is vital for good physical and mental health. You need between 7 and 9 hours of quality sleep every night to benefit from its health effects.

Ignoring bad sleeping habits can be the underlying cause of many health conditions including depression, heart disease and overweight and obesity.

How good quality sleep can help prevent Alzheimer’s disease

Knowing poor quality sleep has negative consequences for the body and brain, is it possible to reduce your risk of Alzheimer’s disease by regularly getting a good night’s sleep?

It may not be as simple as that. Like your body, your brain benefits from a collection of healthy lifestyle factors. Diet, exercise, sleep, breathing and stress management work together to keep us healthy.

Research is beginning to show sleep acts as a rinse cycle for the brain. It is during non-REM sleep the beta-amyloid proteins are “rinsed” out of the brain. The sleep of healthy older adults was observed in a study that examined the effect of lack of quality sleep on the brain, with the title: “Sleep Disturbance Forecasts b-Amyloid Accumulation across Subsequent Years⁷”. The researchers also tracked the build-up of beta-amyloid proteins in the brain.

Insufficient deep sleep, combined with generally poor quality sleep correlates to greater amounts of beta-amyloid protein accumulation, regardless of age, gender and sleep apnea. The researchers concluded sleep could therefore be a possible preventative and therapeutic factor in altering the risk for Alzheimer’s disease or delaying the onset of cognitive symptoms.

Create a healthy sleep routine for brain health

If you want to maintain cognitive function and brain health, it may be time for you to address any issues you have with sleep.

Developing a healthy sleep routine can help you have a better night’s sleep, which will “rinse” out your brain and ensure you wake up refreshed and are firing on all cylinders in the morning. It is never too early to turn your attention toward developing good sleep habits.

10 tips for ensuring better quality sleep:

1. Wake up at the same time every day.
2. Go to bed at the same time every night.
3. Switch off your screens an hour before bedtime.
4. Take a hot bath to relax and prepare for sleep.
5. Have a sleep-supporting snack before going to bed. A warm cup of milk, a banana or a peanut butter sandwich provide sleep-supporting nutrients.
6. Make sure your bedroom is dark.
7. Keep your bedroom comfortably cool.
8. The bedroom is for sleep and sex – not work.
9. Give yourself over to sleep – allow yourself to relax and fall asleep. Try not to force it.
10. Accept what is not under your control. If you struggle to fall asleep, get up and have a glass of water and try again.

For some further info, read some of our simple steps to improving sleep habits or tips for a consistently good night’s sleep.

Good quality sleep promotes brain health

Sleep on its own will not prevent Alzheimer’s disease, but as one of the pillars of a healthy lifestyle, it can help reduce your risk of suffering a cognitive decline in old age. Sleep, especially deep sleep is when your brain is “cleaned up” after a day of focus and concentration. When sleeping well, the build-up of beta-amyloid protein between the neurons is removed so brain structure and function is maintained.

If you struggle to fall asleep and stay asleep at night, and you have a genetic link to Alzheimer’s disease, developing a healthy sleep routine can help you get a better night’s sleep and reduce your risk of developing this condition.

We have identified sleep as one of the five most important pillars for overall health and wellbeing. Let us help you improve your sleep and protect your cognitive health.