A new study linking disrupted sleep patterns to changes in brain regions associated with Alzheimer’s disease is renewing attention about the importance of healthy sleep habits.

Research published in the Journal of the Alzheimer’s Association suggests that fragmented circadian rhythms, irregular sleep and wake cycles, may be linked to shrinkage in areas of the brain tied to memory and cognition. While experts caution that the findings are still preliminary, they say the study adds to growing evidence that poor sleep can have serious long-term health consequences.

“So it’s not a direct linkage that says, you know, if you have fragmented sleep, or if you sleep too much during the day, that you’re obviously going to get dementia,” says Bradley Gleason, MD, internal clinical director, OSF Sleep Lab in Peoria, Illinois. “But the linkage is strong enough, and it points to needing more studies and more data down the road that there could be a significant link so obviously it’s very important to clean up your sleep disorders so that the risk of dementia and Alzheimer’s potentially is lowered.”

Researchers have long known that sleep affects multiple systems throughout the body, including cardiovascular health, immune function and mental performance. The latest findings raise concerns that chronic sleep disruption could also contribute to neurodegenerative diseases over time.

Don’t ignore sleep issues

Dr. Gleason says many people still underestimate the importance of sleep, often delaying treatment for sleep disorders such as insomnia or obstructive sleep apnea.

“We have lots of other data about cardiovascular health and high blood pressure and stroke and all that we know is linked to poor quality sleep and not getting enough sleep,” Dr. Gleason shares. “So absolutely, yeah, you want to take this seriously. I’m obviously biased but we want to attack your sleep problems head on as early as we can.”

The growing role of wearable devices such as smart watches and sleep trackers in monitoring sleep habits can be helpful. But Dr. Gleason stresses that while those tools can provide useful information, they are not always reliable enough to replace formal sleep evaluations.

At the study’s conclusion, researchers found that participants with more consistent daily sleep-wake patterns had larger volumes in the memory-associated brain areas – the hippocampus and parahippocampus – and less shrinkage of the amygdala, a region vital to emotional processing.

When sleep is fragmented, the body becomes stressed according to Dr. Gleason.

Bad sleep impacts your immune system

“So, you’re not sleeping well and therefore you’re going to have the immune-related ways your body kind of fixes itself is not happening and so your cells are dying off and that could lead to some of the study results that now you’re getting atrophy in some of those important brain areas. So that’s what I would say ‘I need to try to fix why are you having these troubles so we can address it now.’”

According to Dr. Gleason, future research will be needed to determine whether poor sleep directly contributes to dementia risk or whether early brain changes themselves disrupt sleep. In the meantime, the message is straightforward: addressing sleep problems early may help protect long-term health.

“There is a link potentially between poor quality sleep and potentially long-term bad outcomes, including memory problems and/or Alzheimer’s disease. It just points to the importance of sleep quality now to avoid those problems later.”

Here are some tips for getting good sleep to potentially help brain health as you age:

• Waking up at about the same time every day
• Getting bright light exposure in the morning
• Staying physically active during the day
• Keeping meals and bedtime consistent
• Limiting long or late naps
• Avoiding caffeine or alcohol too close to bedtime

If you are having trouble getting to sleep or staying asleep, start by talking to your primary care provider. They might also refer you to a sleep specialist at an OSF Sleep Clinic.

Dr. Bradley Gleason

B-roll-Poor sleep and brain issues

It’s no secret that some kids and teenagers get too much screen time in any given day. And that could mean health issues down the road.

According to a study published in the Journal of American Heart Association, kids and teens who spend time on screens and get less sleep have a greater risk for future heart and metabolic issues like high blood sugar, high blood pressure and cholesterol levels.

The study came from data collected from more than 1,000 kids and teenagers from Denmark. Teenagers with excess screen time were especially at risk. Screen time included either watching TV or using electronic devices for videogaming or socialization.

Natasha Noel, MD, a pediatric cardiologist with OSF HealthCare Cardiovascular Institute, says studies like this are invaluable.

“I liked the fact that they highlighted that everyday habits could have an effect on the cardiac health of kids and teens,” she says. “I also liked that they didn't focus on weight alone, but they looked at other metabolic measures like high blood pressure, cholesterol and blood glucose.”

When kids are up late at night, obviously it can impact sleep, which regulates hormones, metabolism and blood pressure.

“When you have lack of sleep for whatever reason, and in this case, maybe late, prolonged screen times, it could increase your insulin resistance,” says Dr. Noel. “It could increase your appetite, your weight, blood pressure levels.”

Dr. Noel adds that more information is probably needed. Since the study reviewed a Danish population, Dr. Noel says the medical community would benefit from a larger and more diverse group of children for future studies. Another study could analyze what types of screens are used, the purposes for which they are used, and the long-term effects on the kids.

“Of the many things they told us was that not only more screen time, but more screen time occurring with less sleep,” she says. “That kind of had an additive effect on cardiovascular risk factors.”

More physical activity 

The study indirectly illustrates the importance of kids and the need for physical activity. If they’re crashed in front of the TV watching movies or playing video games, it could be an indication they are not getting enough physical movement needed for cardiovascular health.

“Physical activity is one of the mainstays of treatment, especially when we do lifestyle management for high blood pressure and high cholesterol,” she says. But even with physical activity, that screen time and less sleep may be independent risk factors for cardiovascular health long term for kids.”

Dr. Noel emphasizes to her patients the importance of incorporating more movement into daily routines. She recommends walking or biking to school, playing outside with friends, or participating in sports or theater.

It’s a conversation Dr. Noel has with many of her patients and their parents. She stresses that she’s not against screen time. But it’s important to set some ground rules – limit the use of screens, no screens in the bedroom when it’s time for bed and keep a consistent bedtime.

“It's not about taking it out of the picture completely. It's about balance and limiting it,” she says. “Believe it or not, the habits children build today, how they eat, how they move, how they sleep and how they use technology, could affect their long-term cardiac health.”

For more information about pediatric cardiology services, visit OSF HealthCare Children’s Hospital of Illinois.

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