Sleep and Alzheimer’s

The numbers speak for themselves – Alzheimer’s cases are growing at an alarming rate and more importantly, the research indicates that the disease may  actually start sooner in life than originally thought. Currently, there exists no cure for the disease, however, it has been proven that it can be slowed down or possibly prevented, in spite of any genetic predisposition. In fact, the science of epigenetics indicates that lifestyle modifications can either turn on or off the Alzheimer’s gene. Aside from exercise and nutrition ( how we feed and fuel our body and brain), sleep might be the most significant variable that we can control. So why is sleep so precious to our existence? It turns out much of our brain health is impacted by not what  happens when we are awake, but rather when we are asleep and allowing for the brain to recover and heal from all the stresses that are imposed upon it.  P. Murray Doraiswamy, M.D., a brain researcher at Duke University writes:  ” a lack of sleep can lead to irreversible brain damage.”

Sleep deficit can go way beyond making you feel tired during the day. The accumulating effect can have real and dangerous implications on brain health. Sleeping less the seven or eight hours a night for extended periods of time has been linked to cognitive decline, memory loss, and Alzheimer’s. Frequently, people who cannot sleep turn to sleep aids. The use of sleeping pills has far reaching consequences and actually disturbs natural sleep patterns. Sleep aids actually cause the adrenal glands to produce to much cortisol which interferes with REM sleep –  impacting immune function and hormonal function placing greater stress on our brain and body. So we wake up tired,  (symptoms of adrenal fatigue), take caffeine to boost the cortisol levels, which further stresses the adrenals and setting us up for a vicious cycle.

When we are asleep our brains do not actually go to sleep. In fact, several parts of our brain are significantly more active at night than during the daytime. One of them is the recently discovered drainage system called the glymphatic system – which behaves like a sewage or recycling system, clearing away all of the brain’s toxins. Tau protein , which is a crucial component of amyloid plaque ( the hallmark of Alzheimer’s), is very actively recycled during sleep. The researchers are not claiming that Alzheimer’s is actually caused by sleep deprivation, but it appears to be a critical player.

Further studies have discovered that extended wakefulness can permanently damage neurons that essential for alertness and cognition. Reduced sleep may also be linked to shrinking of brain volume. It is important to note that it is not clear whether sleep deficit leads to brain shrinkage or whether a smaller brain makes it harder to sleep. Additionally, there are certain chemicals that are secreted during REM sleep that critical for repairing both the body and brain.

During the daytime we are bombarded with thousands of stimuli – auditory, visual and neurosensory. The brain cannot process all of this stimuli and information has it comes in. It turns out much of the “tagging and archiving” of  memories takes place at night while you are sleeping. It has been described this action is similar to what happens in an old fashioned library- books are dropped off during the day, dusted off and cataloged at night. We often hear people complain about short term memory loss yet they can recall old memories in great detail. New information is simply not getting processed. Memory testing actually proves that people who think that they can function optimally on  four to five hours of sleep is not in fact the case.

Acetylcholne – a chemical involved in creating memories is also involved in sleep and dreaming. Apparently, the brain cells that produce acetylcholine are destroyed during the early development of Alzheimer’s, which contributes to a reduction in dreaming. A side effect of one the drugs used to treat Alzheimer’s, Aricept, is its ability to induce vivid dreams.

Take away:

Get 7-8 hours of restorative and quality sleep.

Your brain is very active during sleep, especially during REM sleep.

If you are sleep deprived it is harder to get into REM sleep due to elevated cortisol.

Sleep helps to recycle brain toxins, specifically, Tau proteins which are the building blocks of amyloid plaque.

Extended wakefulness can permanently damage neurons essential for alertness and cognition.