Dementia And Sleep

Unravel the mysteries of dementia-sleep.
Dementia And Sleep
Tom Greenspan
December 21, 2022

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Sleep deprivation has become an epidemic in the modern day, affecting millions of people in all age groups.

A group of people who are particularly susceptible to sleep disorders are dementia patients. Though it is currently unclear if dementia causes sleep disorders or vice versa, it has been well-established that both are linked.

This is especially worrying since a lack of quality sleep may further exacerbate the cognitive issues faced by dementia patients. Thus, it is paramount that sleep disorders in these patients are treated without delay.

So, let’s go through both types of disorders and find out what connects them. Additionally, we will explore a few solutions to the issue of sleep deprivation to help dementia patients sleep well.

How Does Dementia Affect Cognitive Abilities?

Dementia isn’t a single ailment but a group with varying symptoms and after-effects. The element common among each form of dementia is that they result in reduced cognitive and motor abilities. These symptoms become increasingly severe as dementia progresses.

One of the most common forms of dementia is Alzheimer’s disease, which is characterized by memory loss and lack of responsiveness to the environment. Other forms of dementia include Parkinson’s disease, Shy-Drager syndrome, Creutzfeldt-Jakob disease, and more.

Those facing dementia risk may show the following signs and symptoms:

  • Forgetfulness
  • Misplacing objects
  • Losing the sense of direction when walking or driving
  • Losing track of time
  • Confusion in familiar and unfamiliar places
  • Visual impairment
  • Mood changes
  • Loss of decision-making capabilities
  • Problems keeping up with a conversation

Each patient experiences the disease differently, depending on what caused it and their health conditions. There is a complex relationship between dementia and other ailments. Some diseases may lead to dementia, while others may be caused by it.

The Link Between Sleep And Dementia

As mentioned earlier, it’s not clear whether dementia results in sleep disorders or vice versa. This is because both types of ailments have a few common initial symptoms that may make it difficult to pinpoint the root cause.

That said, some symptoms can be used to see if a patient is likely to be developing dementia over time. Conditions like REM Sleep Behavior Disorder (RBD) can be used to predict neurodegeneration as seen in Parkinson’s disease.

So, does dementia cause sleep disorders, or are sleep problems responsible for dementia? As it turns out, both statements stand correct, as evidenced by research. People who slept under five hours were typically more likely to develop dementia than those who found good night’s sleep. Five hours is not enough sleep for a healthy adult, who needs enough slow-wave sleep in particular to function well.

Even so, the link between sleep and dementia leaves a few questions unanswered, such as the reason behind this relationship. The answers discovered thus far are theories that require further research.

One such theory points to the presence of beta-amyloid in the brain, which it forms during active hours and clears out while sleeping. The idea behind the theory is that the brain doesn’t find enough time to clear the protein out with insufficient quality sleep. This results in motor and cognitive decline as this protein builds up, which leads to dementia.

How Sleep Disorders Are Diagnosed In Dementia Patients

Diagnosing common sleep disorders in dementia patients can be difficult due to the shared underlying causes and symptoms. Further muddying the matter is the possibility of a patient displaying symptoms of multiple sleep problems. And factoring in the side-effects of medication and the conditions of patient care facilities, pinpointing the disorder can become a complicated affair.

To simplify diagnosis to a certain extent, sleep disorders are chiefly classified into four categories:

  • Sleep latency or interrupted sleep
  • Patients feel sleepy during the day
  • Breathing difficulties during sleep or high nighttime physical activity
  • Nighttime hallucinations or behavioral shifts

Let’s look at a few common sleep problems to see how they are diagnosed in dementia patients.

1. Insomnia

The symptoms of insomnia can be highly variable, depending on the person suffering from it. These symptoms are generally divided into two sub-categories, namely sleep-onset insomnia and sleep maintenance insomnia. The former denotes the inability to fall asleep, while the latter indicates an inability to remain fast asleep through the night.

Diagnosing a patient suffering from Alzheimer’s disease for insomnia is an extended process that can last up to a month. For a patient to be diagnosed with insomnia, they need to have displayed one of the aforementioned symptoms consistently for a month or longer. 

Insomnia diagnoses require a complete overview of the patient’s medical records, a physical exam, and all the previous prescriptions. 

2. Hypersomnia

Hypersomnia is what is referred to as daytime sleepiness in colloquial terms and is characterized by the patient’s inability to stay alert during the day. As with insomnia, hypersomnia has a few sub-categories of disorders with certain symptoms, such as narcolepsy and idiopathic hypersomnia.

There isn’t enough data on hypersomniac patients who also suffer from dementia or Alzheimer’s disease. As such, doctors may use the standard diagnostic method for detecting the sleep disorder. This includes interviews pertaining to the patient’s sleep, their sleep partners, loss of muscle strength, and more.

For dementia patients, their caretakers may be asked to create and maintain a journal that details the onset and frequency of daytime sleepiness. Additionally, the caretakers will be required to measure the patient’s sleep quality and duration to the best of their ability.

3. Parasomnia

Parasomnia is the adverse physical and emotional reaction displayed by patients during sleep, which is often involuntary. One of the most common forms of parasomnia in dementia patients and the elderly is REM Sleep Disorder (RBD). This is when the patient showcases physical movement that is often violent in nature, which occurs as they dream.

Doctors diagnose parasomnia by studying the patient’s medical history and testing their physical activity during sleep. RBD tends to afflict patients with Parkinson’s disease and Shy-Drager syndrome, which is why diagnoses are coupled with tests for sleep apnea and seizures.

4. Sleep Apnea

Sleep apnea is a disorder where the patient loses breath for a brief period during sleep, disturbing it and waking them up. Not only does this result in poor sleep for the patient, but it also keeps them from going through all the sleep stages.

The ailment is categorized into two types: Obstructive Sleep Apnea (OSA) and Central Sleep Apnea (CSA). OSA is caused by an obstruction in the upper airway, while CSA can be a result of issues with the central nervous or cardiovascular systems.

With OSA in particular, severe snoring is observed in patients, which is often coupled with choking, gasping for air, or nocturia. And these symptoms form the basis of a sleep apnea diagnosis. 

Sleep apnea generally grows worse with age and body weight, and mitigating this sleep disturbance can require medical assistance.

5. Restless Legs Syndrome (RLS)

Restless legs syndrome has the patient suffering from severe pain in their legs that wakes them up from their sleep. The pain can be a result of an itching or tickling sensation that continues to get worse as the night progresses.

While RLS may occur early in a patient’s life, people with dementia develop it as the disease progresses. In those who develop it early, the condition is often secondary in patients as a result of iron deficiency.

RLS cannot be diagnosed in a lab currently beyond general interviews with doctors. The intensity of the painful sensations and the patient’s tendencies and urges can be used to differentiate RLS from other similar conditions.

6. Circadian Rhythm Sleep Disorders

Circadian Rhythm Sleep Disorders (CRSD) indicate a poorly synched circadian rhythm in a patient. It indicates that the inner body clock of a patient that takes care of the sleep/wake cycle doesn’t work correctly. The patient’s daily sleep/wake cycle ends up fragmented over the 24 hours of the day, rather than one phase that lasts six to eight hours.

CRSD is often observed in the elderly who are less physically active and are not exposed to natural light as often. Diagnosing it is a matter of measuring melatonin levels and body temperature to find faults with their sleep patterns. That said, a full screening is still deemed necessary to check for any other physical or psychological disorders that may accompany CRSD.

Treating Sleep Disorders In Dementia Patients

Unfortunately, there are not many effective treatments for sleep disorders for dementia patients. Sleep problems in such patients have to be managed through certain methods and medications to restore their normal sleep pattern. And for those suffering from diseases like Alzheimer’s disease, evidence remains sparse to gauge the effectiveness of medicines meant for those having trouble sleeping.

Those suffering from severe sleep apnea or hypersomnia are usually treated with continuous positive airway pressure (CPAP) machines. This treatment therapy can help alleviate the frequency of sleep disturbances and daytime sleepiness. And there is some evidence to suggest that CPAP machines may help restore some cognitive functionality in dementia patients.

For those diagnosed with RBD, physicians advise caution to mitigate the injury risk factor during sleep. Caretakers, in particular, are advised to remove dangerous objects from the room to prevent any chances of the patient’s involuntary movement causing them harm.

And lastly, some nursing homes and care facilities use sedatives to alleviate sleep disorders. While they may benefit the patient’s sleep, they may also lead to further deterioration of the patient’s cognitive abilities. Use of medications outside of absolute necessity should be avoided at all costs.


Dementia is a serious brain health issue that is becoming progressively common, with some evidence pointing at inadequate sleep as the reason for it. Needless to say, the ailment should be taken quite seriously.

There are a myriad of sleep disorders that can afflict a dementia patient, sometimes multiple at the same time. As a result, it befalls the caretakers to ensure that the patient remains comfortable and sleeps well through the night. 

With an accurate diagnosis from a doctor, the caretakers can help implement positive sleep changes for the patient and improve the patient’s overall health.

For the current generation, which may be susceptible to dementia later in life, mitigating dementia risk is important. And to do so, ensure you get enough deep sleep through the night during a normal sleep duration.