Common sleep issues with dementia

Many older adults have trouble sleeping. But people with dementia often have an even harder time. Sleep troubles may affect up to 25% of people with mild to moderate Alzheimer's and about 50% of people with moderate to severe Alzheimer's. Sleep troubles tend to get worse as Alzheimer's becomes worse.

Sleep issues can include feeling too sleepy during the day, and having trouble falling asleep and staying asleep at night. Waking up often during the night and waking too early in the morning also are common.

Some people with dementia feel a state of confusion that happens in the late afternoon and lasts into the night. This is called sundowning. It may involve feeling confused, restless, anxious and aggressive. Night wandering in this state of mind can be dangerous.

A breathing condition called obstructive sleep apnea also is more common in people with Alzheimer's disease. Obstructive sleep apnea causes breathing to stop and start many times during sleep.

Factors that might play roles in sleep troubles and sundowning include:

• Mental and physical exhaustion at the end of the day.
• Changes in the body's natural "clock" that typically helps people feel alert during the day and sleepy at night.
• A need for less sleep, which is common among older adults.
• Being in a place that's new or has a confusing layout.
• Low lighting and more shadows. This can cause people with dementia to become confused and afraid.
• Pain, hunger or thirst.