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Sleep Disorder Linked to Risk of Dementia

Dementia from a sleep disorder?

Anyone who has a family member suffering from dementia or Alzheimer’s knows how difficult and heartbreaking these illnesses are. And it’s often anyone’s guess as to what ultimately causes dementia in a given person. What about sleep habits?

Well, it turns out that we may have clues now to a link between the development of dementia and a sleep disorder known as rapid eye movement (REM) sleep behavior disorder (let’s call it RBD for short). The facts:

  • With RBD, the paralysis that normally occurs during REM sleep is incomplete or absent, allowing you to "act out" your dreams. Translation: you’re not experiencing typical REM sleep that keeps you in a normal cycle of sleep.
  • These dreams are often vivid and violent, compelling you to talk, punch, kick, scream, and even jump out of bed. Translation: you’re not getting the restful sleep you need.
  • RBD is usually seen in middle-aged to elderly people, and more often in men.

The researchers of this latest study found that 63 percent of people who experienced RBD developed dementia with Lewy bodies or Parkinson’s disease in later life. In some cases the disorder was detected up to 50 years before the neurodegenerative condition developed. It’s not too surprising that RBD is also linked to Parkinson’s, as 30 to 60 percent of people with Parkinson’s disease develop dementia.

FYI: Lewy body dementia is a rare form of demetia whereby small round clumps of normal proteins called Lewy bodies (after their discoverer) become abnormally clumped together inside brain cells. Whether the Lewy bodies directly cause gradual damage to the brain cells, impairing their function and eventually killing them, or are only a marker of some other destructive process is not known.

Scary? We’ve already seen that sleep loss causes brain loss. And when you look at the risk factors for dementia—eating a healthy diet, engaging in regular exercise—both of which have been shown to reduce the risk of developing dementia by up to 60 percent, is there any surprise that getting a good night’s sleep is just as important?

Clearly, we need more studies done to help us understand the associations between sleep habits and our risk for illness later in life. We also need more information on associations that go beyond just rare sleep disorders like RBD. The statistics are far too breathtaking:

  • One in three people over 65 will die with dementia.
  • Twenty percent of us don’t get enough sleep—banking less than 6 hours of sleep on average.
  • Heart disease, diabetes, and obesity have all been linked with chronic sleep loss.

So what can a lifelong battle with insomnia, for example, do to you in your golden years? Insomnia, by the way, is the most common sleep disorder, affecting approximately 64 million Americans regularly each year. Will a seemingly “harmless” struggle to get a good night’s sleep in your prime position your body for ill health later on?

Unfortunately, studies increasingly are pointing to YES. Sleep matters. Today. Tomorrow. And long into our futures.

The single most important thing you can do today to safeguard your health tomorrow might not be just what you eat and how you move. It must also include how well you sleep.

Sweet Dreams,

Michael J. Breus, PhD

The Sleep Doctor™

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