Dementia and Sleep Disorders

Patients suffering from dementia usually sleep poor, and those who are already diagnosed with some sleep disorder will likely get some symptoms of dementia. Read on to learn more about their connection and how to improve sleep when struggling with this condition.

As we age, we are more liable to different illnesses and conditions that usually tend to appear at that stage of life, dementia is only one of many, but it stands as a blanket-term for a few different forms of this condition. Dementia can be considered as a normal part of aging, but not all people experience it in the same way, and with the same symptoms, also, some people are 80, or 90 years old and have not a single sign of it. It is still unclear why some people are more liable to it, while others don’t experience it at all. Loss of memory, thinking, mental skills, etc. are only some of the main characteristics of this disorder, or condition, which often goes hand in hand with other diseases.

Since we were born, sleeping was a substantial part of our lives, and it is still essential even for seniors, but the problem is when some other condition disrupts our sleep, and by doing that it also tackles our health and everyday functioning. Sleep disorders have become our reality, and the more they interfere with other conditions, the harder it is to find the real cause and treat things separately.

So we are going to start from the primary cause, which in this case is dementia. We mentioned that there are a few types of it, but they all represent a pathophysiological condition. The most common type of it, and the one about everyone has at least heard of, is Alzheimer’s disease, some other not so common examples include Lewy body dementia; Parkinson’s disease, vascular dementia, Huntington’s disease, Shy-Drager syndrome, alcohol-related dementia, Creutzfeldt-Jakob disease, and AIDS-related dementia. 

In today’s post, apart from the usual, we will also go through some of the most common questions people have on this topic, hoping this will help you understand this complicated condition a bit better.

What Is Dementia?

We know that it runs among the elderly population, and some of the latest data provided by the Institute for Dementia Research and Prevention show that every sixth woman, and every tenth man older than 55 years, will have some of the symptoms which are related to this mental illness. Although it covers a lot of different diagnoses, in its core, it represents the loss of cognitive functions such as remembering, thinking, reasoning, talking, and also some behavioral features which can aggravate the normal daily functioning. There are a lot of stages of this disease, but while in some more mild phases the patient can keep up with regular operations, in the more severe cases, patients have to depend on someone else, even for the most basic daily things because they are no longer capable of taking care of themselves.

So how this happens? Once our brain nerve cells stop working, they lose the connection with other brain cells, and eventually they die, we all lose some number of brain cells as we get older, but people with this illness lose a significantly higher number of these cells; hence, they develop these symptoms. 

We mentioned that dementia is used as a term which covers several diseases; they differ by their cause or the type of brain change. The most known and common type of it, the Alzheimer, effects from 60% to 70% of all patients who suffer from it, and it is connected to the loss of cognitive functions. To get the idea how widespread Alzheimer’s disease is in the US, we would like to share the data that currently around 5.5 millions of Americans are living with it, and experts predict that by 2020. that number will increase up to 14 million. Vascular dementia is also a common type of it, and it affects the blood flow going to the brain, and in the worst case scenario, it causes a stroke. Lewy body dementia is also quite often, around 1.4 million Americans are diagnosed with it, but because of the high resemblance with Alzheimer and Parkinson’s disease, many patients are often misdiagnosed, so it is estimated that the number of people is even higher.

When it comes to predispositions, age is the primary factor, and the senior population is the category of people who are mostly suffering from this disease. Besides age, people who have cognitive impairment or neurodegenerative diseases are also at a higher risk of this disease.

About Dementia and Sleep Disorders

These two have a very complicated relationship, in most cases, they go together, and often cause each other’s symptom, which means that patients who suffer from one of these two have a higher chance for developing the other one.

Patients suffering from this disease usually have a poor sleep, and those who are already diagnosed with some sleep disorder will likely get some symptoms of dementia. Researchers are generally struggling to give the right answer because they also are not sure how it works, so the situation between these two reminds a little bit on the tale as old as time, what is older, the chicken or the egg?

Seniors usually have a poor sleep, and they tend to sleep less, wake up often, or go to sleep with a lot of worries on their mind, even 40% of them have some sleep-related problems. Insomnia is, of course, the predominant disorder among seniors, followed by sleep apnea, RLS, RBD, PLM, etc. which all start to develop as we age. For people who have a mental illness, two sleep disorders are symptomatic. 

For example, RBD denotes Lewy body syndrome, but it can also be observed as an early indicator of Parkinson’s disease. It is the same with Alzheimer and obstructive sleep apnea because OSA can contribute to Alzheimer’s pathopsychology. 

Patients with this illness who have done the polysomnogram tests have increased sleep fragmentation, longer sleep latency, decrease in sleep time, and sleep efficiency. Their main symptoms are excessive daytime sleepiness, confusion, nighttime wanderings, and sundowning, for which the causes are still unknown. They progressively have an increased time of nighttime awakenings, and less and less REM sleep during the night. People living with Alzheimer’s have the neuronal degeneration which damages the forebrain and reticular region of the brain system, which are the two areas in charge of regulating sleep, that is why their sleep patterns go through substantial changes.

Excessive daytime sleepiness hits from 30% to 50% of all Alzheimer patients, and as the disease progresses, this symptom becomes more prominent and aggravates, the same is with Parkinson’s patients and insomnia, for example, in one of the studies which focus on the relationship between Alzheimer and sleep, the connection between elderly population and insomniacs has been found in a higher rate of beta-amyloid plaques in their brains, in comparison to those of healthy people.

Sleep Apnea and Dementia

Snoring as the typical sign of sleep apnea can also be something that patients with mental illness will experience. Sleep apnea cannot be the direct cause of it, although many claim that it can. A study which caused many controversies states that sleep apnea drains the oxygen away from the brain during the night. This study included 83 participants who all had problems with memory or the first potential sign of Alzheimer’s. Since this was a small study, with a lot of limitations, it is hard to take their conclusions for granted, for example, although all participants reported having issues with their memory, their memory and sleep were measured only one time, and the most important thing is that no one of them was officially diagnosed with sleep apnea. This study was performed in Australia, and publishing of its results lead to many premature conclusions and misunderstandings because when we consider all the information, we cannot rely on those results. The results were accurate, but they failed to prove that sleep apnea caused patients symptoms.

Insomnia and Dementia

The idea that people who have insomnia have a higher risk of dementia has been a subject of many studies, a more recent one, suggests that that connection could be possible. The link lies in the number of amyloid-beta proteins, which rises when we are awake, and goes down during sleep. This protein also creates some of the brain plaques, which were found in patients with Alzheimer’s.  

Irregular sleep can be one of the early signs of this disorder; patients who noticed changes in their sleep reported having restless nights, excessive daytime sleepiness, and extended naps. Healthy people take daytime naps that last around 20 minutes, but people with Alzheimer’s can have naps, which can last even 3 hours, and that is the main predictor of this disease.

A team of Canadian researchers was trying to determine when and how early will the symptoms of Alzheimer’s start showing off. Their study processed data from more than 14,000 healthy people who were included in the extensive international health survey in which people older than 50 years old from 12 countries were included. They concluded that the participants who have had restless nights, tiredness during the day and the need to use sleep pills, are more liable to be diagnosed with Alzheimer’s at some point in the next two years.

A neurologist from Missouri, dr Holtzman agrees that sleep disturbances are the first sign of the brain changes which cause the disease. Together with colleagues researchers, Holtzman performed a study on mice, the mouse with Alzheimer had an irregular sleep-wake cycle and increased number of amyloid-beta plaques, when the plaques were eliminated, the course went back to normal, which leads to the conclusion that plaques cause sleep irregularities. However, to prove if this is the case with humans as well, would require plenty of long-term studies.

How to Diagnose a Sleep Disorder in Patients With Dementia

It is never an easy task to set a diagnosis of some sleep disorder, a lot of them have similar features, but they can also be easily confused with other conditions. But, with patients who suffer from mental illnesses, the situation is even more tricky since there are a lot of underlying causes, too common symptoms and mitigating factors. When we speak about patients with this disease, sleep regulations splits into four categories:

  • Excessive daytime sleepiness, also known as hypersomnia
  • Issues with falling and staying asleep
  • Unusual behavior and nocturnal hallucinations
  • Troubles with breathing during sleep, such as sleep apnea, and restless leg syndrome

Of course, patients can have one, or more of these symptoms combined, to be diagnosed with this mental illness. A complex of different symptoms complicates the road to diagnosis.

Next, we will like to present the diagnostic criteria which are used to evaluate sleep disorders among seniors and patients who have been diagnosed with dementia.


The intensity and symptoms of insomnia tend to vary from one person to another, but this disorder can usually split into two groups, one is called sleep onset insomnia, and it refers to people who have problems with falling asleep, while the other one is sleep maintenance insomnia, and it stands for inability to stay asleep during the night. Insomnia is usually considered for an initial condition, since it develops independently, as an initial condition, but it can also coexist with many other disorders.

Many people are struggling with their sleep, but to be diagnosed with insomnia, a patient must be experiencing insomnia symptoms or problems with staying and falling asleep for at least a month. There is also an option to be diagnosed with chronic insomnia, which happens rarely, and usually among older adults. Since many of seniors use a lot of different medications, that has to be taken into consideration as well, so the diagnosis requires a detailed inspection of the patient’s medical history with all of its prescriptions and previous conditions.


Hypersomnia is another broad term which can cover a lot of different conditions which cause excessive daytime sleepiness but are not connected with sleep deprivation and insomnia. Some of them are idiopathic hypersomnia and narcolepsy, which can show off on their own, but they can also be triggered by some other substances or medications with side effects. People who suffer from hypersomnia cannot stay awake and alert during the usual morning waking hours. There is not a lot of studies of hypersomnia among seniors, and the doctors have to use the same diagnostic criteria which they use for the younger population, they usually inspect the patient’s medical history and some of the symptoms which often follow narcolepsy. Some of them are cataplexy and weak muscles, but mostly the patients will be asked to create a sleep journal in which they will note all of their sleepy episodes during the day, and the amount of sleep they get during the night.

Sleep Apnea

Sleep apnea is one of the more severe types of sleep disorders cause it involves occasional breathing stops during sleep, and we differ two main types of it. Obstructive sleep apnea, which refers to the obstruction of the upper airway, and the central sleep apnea, which occurs because of some cardiovascular problems or due to the issues in the central nervous system.

Common signs and symptoms of sleep apnea include severe snoring, choking, and nocturia, and they are pretty often among the elderly and obese population.

Restless Leg Syndrome

RLS is a sleep disruptive disorder; people who suffer from it experience painful and tickling sensations in their legs, and those sensations are so intense and persistent that they can wake up the sleeper. RLS can be developed independently from other conditions, but in the vast majority of cases, it is a secondary condition which most likely occurs due to the iron deficiency. 

Diagnosing RLS can be challenging since there are no proven lab tests which can diagnose it; instead, the doctors have to rely on patients reports and based on that to determine whether or not is RLS a proper diagnosis for them. RLS patients feel very intense pain during the night, and an urge to move their legs while their body is resting, so physicians focus on those symptoms when trying to identify and seclude RLS from other similar disorders that cause leg pain.

Circadian Rhythm Sleep Disorders

This group of disorders manifests in regular sleep patterns which happen at unusual times, mostly because the patient’s internal circadian clock is in disbalance. Some of the common types of CRSD are irregular sleep-wake disorder and advanced sleep phase disorder. ASPD patients are mostly known as early birds since they tend to go to sleep earlier and wake up before others. ISWD patients have fragmented sleep because they can hardly pull off full 7 or 8 hours of sleep at night, and their rest is split into several portions during the 24-hours. 

CRSD especially hit the senior population, because of the natural aging changes which occur in their circadian rhythm, lower level of physical activity, and also less exposure to sunlight. Researchers rely on body temperature and the level of melatonin to determine if the patients have a disorder of their circadian clock. Since a lot of sleep disorders share similar symptoms, and these symptoms can sometimes be misleading, doctors have to do a full screening to exclude the possibility of other sleep disorders, and some psychological ones such as anxiety, depression, etc.


Parasomnia is a category of sleep disorders or a parachute-term which covers disorders with abnormal behavior, movements, emotional or physical reactions, and perceptions which can occur during sleep. The most common type of it which strikes seniors and patients who have a mental illness is a REM sleep disorder or REM behavior disorder. RBD is characterized by physical movements which are usually violent and can harm the sleeper or its partner. Other types of parasomnias are sleepwalking, night terrors, and enuresis, but these disorders typically strike children and teens, and they are rare among adults.

RBD is diagnosed after a detailed inspection of patients medical history, tests which show the level of muscle activity during sleep, but it often goes hand in hand with dementia, Shy-Drager syndrome and Parkinson’s disease. 

Essential Questions

Due to the vast number of similar conditions, symptoms, diagnosis, and also the complicated relationship between a lot of these disorders, most of the doctors agree that the patient’s answers and experience are crucial for setting a proper diagnosis. A specific study even published a list of questions that can be of vital help to the doctors to determine a sleep disorder and eliminate other similar ones. Here we share the list of notes and questions, so you can think about them, prepare the answers, and have enough time to remember all the details.

  • At what time do you usually go to bed at night and when do you wake up in the morning?
  • Estimate, how many times do you wake up during the night?
  • Have you ever had some struggles with falling asleep at night?  
  • When you wake up at night, how long does it take before you fall asleep again?
  • Does your partner claim that you are moving or kicking in your sleep?
  • Does your partner claim that you have issues with snoring, breathing stops, or gasping for air? 
  • Are you aware that you tend to move, walk, talk, kick, or punch while you are sleeping?
  • Do you feel tired or sleepy most of the time?
  • Do you ever involuntarily doze-off during the daytime?
  • How many naps do you usually have during the daytime?
  • How much sleep do you need to feel functional and alert during the day?
  • Are you taking any medication or other things that are helping you with your sleep at the moment?

How to Treat Sleep Disorders in Patients With Dementia

Even though modern medicine is very advanced, and researchers are working hard on discoveries each day, there are still no effective cures for both, only the treatments that can alleviate these conditions to some point. Some medications are capable of improving cognitive abilities of patients with this condition, but the remedies for reducing symptoms of sleep disorders in people with mental illness are still not pinpointed.

Many effective treatments for sleep disorders include significant lifestyle changes; however, it has not been researched how that works on people who also have a mental illness, and if it would mild their other symptoms. 

Sleep-disordered breathing or sleep apnea is pretty often among patients, but it can be treated with CPAP machines, which patients with dementia can only stand for around five hours each night. The CPAP treatment has proven to be useful since it lowers the number of SDB episodes from 24 to 10 during each hour of sleep. Other benefits of this therapy are less snoring, better mood, and improved quality of life, but there are also some indications that it can slow down the process of cognitive impairment. 

Bright light therapy is getting more and more popular, and it is being used for various reasons. A study gathered 8 patients with Alzheimer’s, 4 with vascular dementia, and 5 with LBD, to explore how light therapy can improve their sleep patterns. The participants had only one task, to sit in front of a light box for one hour, every morning for two weeks. A slight improvement was noticed in 4 participants with a more mild type of Alzheimer who were diagnosed in the near past. In conclusion, further and larger studies will be needed, to determine in which stages of illness light therapy can be beneficial. Melatonin and melatonin supplements are also effective for improving the symptoms of sleep disorders, especially insomnia, but also for some signs of Alzheimer’s disease.

Today the precaution measures have become essential, especially for patients with RBD, because the risk of injuries during the night is always present. It is necessary to create a safe sleep environment, to remove any dangerous objects, weapons, lock the doors and windows, and visit a doctor for regular check-ups so that the progress of brain diseases can be monitored and recorded. Sedatives are widely used in many nursing homes because they can ensure the night of full sleep, but they should not become a habit because they can further damage the cognitive functions.

Tips For Relieving Symptoms of Dementia

Besides already mentioned treatments and medications, there are some beneficial things that every patient can do to mitigate the symptoms of sleep disorders.

  • Create a sleep schedule. For regular circadian patterns, the most important thing is to maintain a healthy sleep routine. Patients should try to go to bed and wake up at the same time. It will be difficult in the beginning, but soon they will get used to it, and start noticing the benefits. 
  • Natural light therapy. We mentioned indoor light therapy, but the outdoor therapy with natural light is just as efficient. Studies have shown that exposure to sunlight is highly beneficial for older people with Alzheimer and their sleep.
  • Physical activity. Even though seniors are not able to be active as when they were younger, they can still do some lighter exercises, or walk, because that could exhaust them and make them sleepy.
  • Personalized diet. Eating balanced and healthy meals is always a good thing, but there are some diets composed of sleep inducing foods. Calcium-rich products such as milk, cheese, and other dairy products can induce sleepiness, and oatmeal raises the blood sugar level, which causes drowsiness. 

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