Dementia’s Effects on the Sleep Cycle

Nearly 46 percent of aging adults report having trouble sleeping at one time or another. Dementia adds another dimension to the growing problem of sleeplessness amongst older adults, as some studies have shown that nearly a quarter of Alzheimer’s patients alone suffer from disrupted sleep. Other forms of dementia create similar sleep problems that can be distressing for both the person with dementia and their caregivers.

Dementia and The Circadian Rhythms

Dementia interferes with the circadian rhythms. Circadian rhythms are 24-hour biological and physiological cycles the body uses to regulate everything from the sleep-wake cycle to eating patterns. Dementia affects the brain and nervous system, which is used by the circadian rhythms to control the sleep-wake cycle. Natural light triggers the circadian region of the brain but dementia may disrupt those signals, leading to unpredictable sleep-wake patterns.

With dementia already causing problems for the central nervous system, the normal effects of aging may limit the amount of light that enters the eyes to stimulate the circadian region. What light does enter may have trouble reaching the right parts of the brain to stimulate the circadian region due to dementia’s interference with the nervous system, further complicating the regulation of the sleep-wake cycle.

Dementia and Sundowning

Those with dementia may also suffer from sundowning, an anxiety syndrome that occurs at dusk. Sundowning can be recognized by fear, restlessness, and sometimes aggression late in the day. There’s evidence that dementia causes the parts of the brain that control attention, emotions, and arousal to experience an increase in activity near sunset. When fatigued and the changing shadows and light associated with evening are added into the mix, a transition from wakefulness to sleep can be very difficult.

Reducing Sundowning, Supporting Circadian Rhythms, and Getting Better Rest

For the elderly, there can be a lot of barriers to quality sleep. Dementia and other medical conditions may require the use of medications that further disrupt sleep. The elderly are also at higher risk for aches and pains that make it hard to get comfortable at night. Despite these challenges, there are ways to treat circadian rhythm disorders as well as personal habits that support healthy sleep.

Circadian rhythms can be supported by increasing natural light exposure early in the day. A walk outside or time spent sitting on the front porch are comforting ways to increase exposure. During the winter months or if the person is homebound, bright light therapy might help. This therapy uses a full-spectrum fluorescent bulb to mimic sunlight. When done early in the morning, it can increase the amount of light that reaches the circadian region of the brain, regulating the sleep-wake cycle.

At night, work to establish a regular bedtime schedule and routine. Routines might be hard to remember for those with dementia, but consistency brings predictability to their life. Bedtime routines should include familiar activities that help them feel calm like changing into comfortable pajamas, spending a few minutes listening to quiet music, or drinking a warm glass of milk.

It’s also important to get comfortable at night. The elderly may have to deal with oxygen masks and tanks, CPAP machines, or other medical devices that require some maneuvering to get comfortable. Incorporate adjustments for comfort into the bedtime routine so it’s not rushed or stressful.

Dementia may cause changes to the sleep-wake cycle, but they can be addressed and treated. Bedtime may present a few extra challenges but with a plan in place, everyone can get more sleep.

Authored by Mary Lee. Mary Lee is a researcher for the sleep science hub Tuck.com. She specializes in sleep’s role in mental and physical health and wellness. Mary lives in Olympia, Washington and shares her full-sized bed with a very noisy cat.