Dementia and Sleep Disorders

Information is taken from Mattress Clarity, www.mattressclarity.com/blog/alzheimers-and-sleep

Dementia and sleep disorders share a paradoxical ‘chicken and egg’ relationship. While many people living with dementia tend to experience poor sleep on a regular basis, patients diagnosed with certain sleep disorders – such as insomnia and sleep apnea – are also more likely to develop dementia symptoms.

The Relationship Between Dementia and Sleep Disorders

Three categories of people are at a heightened risk of dementia: the elderly, patients with neurodegenerative diseases, and patients with mild cognitive impairment. Although 40% of elderly patients have sleep-related complaints, sleeping disorders like insomnia are less common in healthy older people and are more often associated with comorbidities.

In addition to insomnia, other sleep disorders, such as sleep apnea, REM sleep behavior disorder (RBD), restless legs syndrome (RLS), periodic limb movements (PLMs) and sleep-disordered breathing (SDB), become more prevalent with increasing age. RBD and sleep apnea are of particular interest with regard to dementia. RBD is used as a contraindication of Lewy body dementia, and may also be used as prognostic and predictive tools for neurodegeneration in Parkinson’s disease. Similarly, obstructive sleep apnea (OSA) has several common causal factors with Alzheimer’s disease; OSA is also widely believed to contribute to the pathophysiology of Alzheimer’s.

The most common sleep disorder symptoms in patients with dementia are increased daytime sleepiness, nighttime wandering, confusion, and agitation (also known as sundowning). Many suspect these behaviors are related to the early circadian cycle of senior citizens.  Neuronal degeneration in Alzheimer’s contributes to the sleep pattern changes by damaging the two regions of the brain that help regulate sleep patterns. The characteristic plaques of AD have even been found in the brains of elderly insomniacs who have not been diagnosed with Alzheimer’s or other dementia-related conditions.

Dementia and Sleep Apnea

Dementia patients often exhibit the symptoms of sleep apnea, such as chronic snoring and/or temporary loss of breath during sleep. Many experts believe that sleep apnea is directly correlated to induction of severe dementia, and vice versa; even though sleep apnea does not directly cause dementia, the effects of sundowning and persistent hypoxic conditions can symptomatically amplify dementia-related symptoms. Sleep-disordered breathing episodes are quite common; 90% of people with moderate-to-severe Alzheimer’s experience at least five respiratory events per hour of sleep. The overall prevalence of SDB in patients with dementia varies between 33% and 70%.

Insomnia as a warning sign of dementia

A recent study suggests a link between sleep deprivation and increased risk for Alzheimer’s. Levels of amyloid-beta protein in the bloodstream rise during waking periods and decline during sleep. This protein makes up some of the brain plaques found in Alzheimer’s patients. Sleep problems can be an early indicator of dementia. Alzheimer’s patients often see changes in their sleep patterns early on; what was once a 20-minute daytime nap now stretches to several hours per day. In a recent long-term longitudinal study, older people who complained of daytime sleepiness, restless nights, and increased use of sleep aid medications were much more likely to develop Alzheimer’s symptoms within two years.

Diagnosing Sleep Disorders in Dementia Patients

Accurately diagnosing sleep disorders in dementia patients can be quite tricky, due to an abundance of underlying causes, mitigating factors and common causal symptoms. In patients with dementia, sleep disturbances are generally categorized into four different categories:

  • Trouble falling or staying asleep (insomnia)
  • Excessive daytime sleepiness (hypersomnia)
  • Difficulty breathing during sleep (apnea) or excessive nighttime physical activity (such as restless leg syndrome)
  • Nocturnal hallucinations and/or behavioral problems

It should be noted that dementia patients may simultaneously exhibit symptoms of more than one complex; this sort of co-morbidity can further complicate the diagnostic process. Additionally, sleep disorders can occur due to other factors, such as medication side effects or conditions of long-term care facilities.

Treatment of Sleep Disorders in Dementia Patients

Effective cures remain elusive for both dementia and dementia-related sleep disorders, but certain treatment methods can alleviate most of the persistent symptoms.

  • Using a continuous positive airway pressure (CPAP) machines to treat sleep apnea.
  • Use bright light exposure to regularize sleep patterns.
  • Melatonin and melatonin agonists have also attracted attention in recent years as a possible method of mitigating insomnia and other sleep disorders, as well as addressing symptoms of Alzheimer’s.

Ways to Improve Dementia-Related Sleep Issues

  • A consistent sleep schedule: In order to maintain regular circadian patterns, dementia patients should strive to fall asleep and wake up at the same time every day.
  • Outdoor and photo light therapy: Exposure to natural sunlight will help elderly people realign their circadian rhythm and reduce the effects of sleep disorders like insomnia and CRSDs.
  • A customized diet: Elderly people with sleep disorders can supplement their meals with foods that help them sleep. For instance, calcium (found in milk, cheese, and other dairy products) is known to trigger melatonin and induce sleepiness. Oatmeal and other grains achieve the same end by raising blood sugar, which can lead to sleepiness. Alternatively, people with dementia-related sleep disorders should avoid excessive amounts of foods, drinks, and substances that hinder sleepiness; these include alcohol, tobacco, and caffeine.
  • Physical activity: Even light physical activity can lead to higher levels of sleep. Encourage daytime and nighttime stretching.

A healthy sleep space: Creating, and maintaining, a healthy sleep environment is crucial for mitigating the symptoms of dementia-related sleep issues. Beds should be reserved for sleep and sex, and patients should avoid other activities in bed, such as eating or watching television. Additionally, bedrooms should remain dark and relatively quiet during normal sleep times; keep the blinds drawn, and adjust the temperature to ensure comfort throughout the night.