Nav: Home

Sleep apnea may be linked to higher levels of Alzheimer's biomarker in brain

March 03, 2019

MINNEAPOLIS - People who are witnessed by a bed partner to have stopped breathing during sleep may have higher accumulations of an Alzheimer's disease biomarker called tau in an area of the brain that helps with memory, according to a preliminary study released today that will be presented at the American Academy of Neurology's 71st Annual Meeting in Philadelphia, May 4 to 10, 2019.

Obstructive sleep apnea is a condition that involves frequent events of stopped breathing during sleep, although an apnea may also be a single event of paused breathing during sleep.

Tau, a protein that forms into tangles, is found in the brains of people with Alzheimer's disease.

"A person normally has fewer than five episodes of apnea per hour during sleep," said study author Diego Z. Carvalho, MD, of the Mayo Clinic in Rochester, Minn., and a member of the American Academy of Neurology. "Bed partners are more likely to notice these episodes when people stop breathing several times per hour during sleep, raising concern for obstructive sleep apnea. Recent research has linked sleep apnea to an increased risk of dementia, so our study sought to investigate whether witnessed apneas during sleep may be linked to tau protein deposition in the brain."

The study involved 288 people age 65 and older who did not have cognitive impairment. Bed partners were asked whether they had witnessed episodes of stopped breathing during sleep.

Participants had positron emission tomography (PET) brain scans to look for accumulation of tau tangles in the entorhinal cortex area of the brain, an area of the brain in the temporal lobe that is more likely to accumulate tau than some other areas. This area of the brain helps manage memory, navigation and perception of time.

Researchers identified 43 participants, 15 percent of the study group, whose bed partners witnessed apneas when they were sleeping.

Researchers found those who had apneas had on average 4.5 percent higher levels of tau in the entorhinal cortex than those who did not have apneas, after controlling for several other factors that could affect levels of tau in the brain, such as age, sex, education, cardiovascular risk factors and other sleep complaints.

"Our research results raise the possibility that sleep apnea affects tau accumulation," said Carvalho. "But it's also possible that higher levels of tau in other regions may predispose a person to sleep apnea, so longer studies are now needed to solve this chicken and egg problem."

Limitations of the study included its relatively small sample size and preliminary nature of the study requiring future validation. Furthermore, a lack of sleep studies to confirm the presence and severity of sleep apnea and a lack of information regarding whether or not participants were already receiving treatment for sleep apnea is another serious limitation.
-end-
The study was supported by the National Institutes of Health.

Learn more about brain health at BrainandLife.org, home of the American Academy of Neurology's free patient and caregiver magazine focused on the intersection of neurologic disease and brain health. Follow Brain & Life® on Facebook, Twitter and Instagram.

The American Academy of Neurology is the world's largest association of neurologists and neuroscience professionals, with more than 36,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, stroke, migraine, multiple sclerosis, concussion, Parkinson's disease and epilepsy.

For more information about the American Academy of Neurology, visit AAN.com or find us on Facebook, Twitter, Instagram, LinkedIn and YouTube.

Media Contacts:

Renee Tessman, rtessman@aan.com, (612) 928-6137

Angharad Chester Jones, achester-jones@aan.com, (612) 928-6169

American Academy of Neurology

Related Memory Articles:

Taking photos of experiences boosts visual memory, impairs auditory memory
A quick glance at any social media platform will tell you that people love taking photos of their experiences -- whether they're lying on the beach, touring a museum, or just waiting in line at the grocery store.
Think you know how to improve your memory? Think again
Research from Katherine Duncan at the University of Toronto suggests we may have to rethink how we improve memory.
Improving memory with magnets
The ability to remember sounds, and manipulate them in our minds, is incredibly important to our daily lives -- without it we would not be able to understand a sentence, or do simple arithmetic.
Who has the better memory -- men or women?
In the battle of the sexes, women have long claimed that they can remember things better and longer than men can.
New study of the memory through optogenetics
A collaboration between Universitat Autònoma de Barcelona and Harvard University pioneers the increase of memory using optogenetics in mice in Spain.
Peppermint tea can help improve your memory
Peppermint tea can improve long-term and working memory and in healthy adults.
A new glimpse into working memory
MIT study finds bursts of neural activity as the brain holds information in mind, overturns a long-held model.
Memory ensembles
For over forty years, neuro-scientists have been interested in the biological mechanisms underlying the storage of the information that our brain records every day.
What is your memory style?
Why is it that some people have richly detailed recollection of past experiences (episodic memory), while others tend to remember just the facts without details (semantic memory)?
Watching a memory form
Neuroscientists at Rosalind Franklin University of Medicine and Science have discovered a novel mechanism for memory formation.

Related Memory Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#529 Do You Really Want to Find Out Who's Your Daddy?
At least some of you by now have probably spit into a tube and mailed it off to find out who your closest relatives are, where you might be from, and what terrible diseases might await you. But what exactly did you find out? And what did you give away? In this live panel at Awesome Con we bring in science writer Tina Saey to talk about all her DNA testing, and bioethicist Debra Mathews, to determine whether Tina should have done it at all. Related links: What FamilyTreeDNA sharing genetic data with police means for you Crime solvers embraced...