By Barbara Pierce
“Healthy brain function requires healthy sleep,” said Roger Wong, Ph.D., assistant professor, SUNY Upstate Medical University.
“Not only are poor and insufficient sleep risk factors of dementia, sleep problems are also a known symptom of having dementia,” he continued. “It’s long been accepted that there’s a connection between sleep and dementia.”
Dementia changes the body’s natural sleep-wake cycle, or circadian rhythm. Because of this dysfunction, patients are often unable to follow a 24-hour sleep-wake cycle and instead sleep more during the day and less at night.
Could not getting enough sleep even cause dementia?
“Studies have long questioned the sleep-dementia relationship. It’s similar to the chicken-egg metaphor,” he said. “Which comes first –– does poor sleep cause dementia, or does dementia cause poor sleep? Research suggests the answer to both questions is yes.”
One study found that individuals who slept less than five hours per night were twice as likely to develop dementia compared to those who slept six to eight hours per night, he said. Another study found a 30% increase in dementia risk associated with sleeping six hours or less.
Wong is searching for answers about the relationship between insomnia and dementia because his aging parents have difficulty sleeping. He investigated the literature but did not find clear indications of what his parents’ insomnia could mean for their risk of dementia.
“This is personally affecting my family right now. I want to look at the data,” he said.
He began his own research, which was recently published in the American Journal of Preventive Medicine. Key insights he shared with us:
1. Getting healthy sleep is like running a dishwasher cycle in your brain
Wong explained that one theory of why inadequate sleep increases the risk of dementia involves a protein in our brains called beta amyloid. Beta amyloid is the protein that makes up the plaque found in the brains of people with impaired brain function and Alzheimer’s. During the day, our brains naturally make this protein. At night when we sleep, our brains flush the protein away. Insufficient sleep may limit the brain’s ability to remove beta amyloid and other substances, causing them to build up until they cause dementia.
When in a deep sleep, the beta amyloid is drained away, he explained. That’s why deep sleep is critical for us. It’s like a dishwasher for the brain. You put dishes in your dishwasher when they have a buildup of dirt and grime. That dirt, grime, and residue are like the beta amyloid proteins in our brain that we know are associated with dementia risk. Sleep washes them away.
To achieve restorative sleep requires seven to eight hours of sleep. Cycling through the stages of sleep — from drowsy to light sleep to deep sleep, where the brain repairs itself, and REM sleep, where dreaming occurs — is essential. It’s critical that sleep be continuous and uninterrupted. Ensuring that you’re getting enough sleep allows your brain to go through these important cycles and fosters brain health.
Those with a healthy sleep pattern wake feeling refreshed and clear-headed, with energy and in a good mood. Those who are sleep deprived or have poor sleep quality may struggle to wake up, feel irritable, depressed or anxious, struggle to focus or feel tired throughout the day.
2. Taking sleeping pills as directed by a doctor is fine — in moderation
Long-term use of sleeping pills is linked with a higher dementia risk. Wong’s research, as well as many others, showed that long-term use of sleeping pills is associated with an increased risk of dementia. However, with all the medications that older adults take, it can be unclear whether the sleeping medicines are a significant cause, he added.
3. If you’re having persistent sleeping issues, consult a specialist
For people experiencing persistent insomnia or other sleep issues, Wong recommended speaking with a sleep specialist. His research found that sleep medications haven’t really been shown to be effective for chronic sleep disorders.
“For those with more chronic sleep disorders, I would encourage you to talk to your health provider about non-pharmacological interventions,” he stated. One non-pharmacological intervention, cognitive behavioral therapy, has been shown to be effective in improving sleep.
Promoting healthy sleep habits is also vital: Going to bed at the same time every night, not using a smartphone or watching TV when you’re trying to fall asleep. Consider a calm-down routine that helps you relax as you prepare to sleep. Sleep in a cool, dark room.
Also, caffeine can affect many; it can take up to eight hours for the effects to wear off. Alcohol may lead to poor quality sleep, as may eating large meals close to bedtime.
If you have sleeping issues, considering these approaches can make the difference in falling and staying asleep — and that’s good for the brain.