The Importance of Sleep for a Healthy Life

Transcript

Nathaniel Chin: Welcome to Dementia Matters, a podcast created by the Wisconsin Alzheimer's Disease Research Center. It's our goal to humanize Alzheimer's research so that our community, our patients, our participants in, anyone else interested, can get a better understanding of the work that's happening to fight back against this disease. My name is Nathaniel Chin and I'm a geriatric and memory clinic physician at the University of Wisconsin. I'm also the family member of someone living with dementia. I'll be serving as your host for this podcast and asking the questions I believe on the minds of many in our community. Thanks for joining us.

Today, our guest on Dementia Matters is Dr. Steven Barczi, a professor of medicine and co-clinical director of the division of geriatrics at the University of Wisconsin School of Medicine and Public Health. Dr. Barczi is nationally recognized as a medical educator for his work in training medical students in geriatric medicine at both the med school and at the Veterans Administration Hospital in Madison. He is one of a handful of geriatric sleep physicians in the country. I'd like to start by bringing up an article that one of our researchers at the Wisconsin ADRC recently published. They were looking to determine the relationship between sleep quality and markers of Alzheimer's disease in late middle life and what they found was that the self report of poor sleep was associated with greater Alzheimer's disease related pathology in people who are healthy but at risk for Alzheimer's disease, and I'm wondering what does poor sleep mean?

Steve Barczi: So it'd be good to start out by thinking of why is it that we need to sleep because that's one of those age old questions and maybe 20 or 30 years ago there was a lot of speculation about the purposes of sleep. Now we have a much better understanding with lots and lots of research work that's been done. So I think it's fair to say that sleep has a restorative role. It helps us to physically feel better. It helps take away that sense of tiredness that accumulates the longer we're awake, but beyond that restorative role alone, it has several other important roles, if you will. Number one, it helps us with regards to consolidation of memory. So we're starting to learn, and actually it's been in the last 15 years that certain aspects of sleep help us to consolidate certain things that we remember from the proceeding day. So we learn new information, we experience new things, we might even have emotional kinds of events that occur and our brain has to process that information and it has one of several ways you can do so. Number one, it can disregarded it, I'd like to use an example that we don't remember, I certainly don't remember what I had for breakfast three weeks ago. It's not useful information and so my brain has decided to get rid of it. On the other hand, if some important event occurs, like a family member has a baby or a health issue comes up or someone dies; those are big life events that usually imprint us and those kinds of events tend to be reinforced in deep or slow wave sleep. So our brain has a way of pruning out some of the information that's not so important and storing or reinforcing the neural connections or networks during sleep for more important information. So that, you could imagine, would be very important for this whole issue of dementia. Additionally, it helps us with regards to regulating certain emotional events and responses, so everyone here probably can appreciate that if you have a really bad night's sleep or hardly sleep at all, the next day you're a little bit more prone to kind of be inflammatory to others or say things you shouldn't normally say.  And so this way of regulating emotional response is also, it turns out to be an important kind of piece of sleep. We also know that sleep has a role on the whole body's maintenance. So for example, people who sleep poorly generally experience more problems with elevations in blood pressure, for example. So these are all really important tasks. Now to get back to the very first point you made, which is what does it mean to have poor sleep? That may mean different things, depending on how you approach it. It could mean that by having poor sleep you feel worse, in some fashion. You may not be as mentally sharp, you may be just more dragged out, you may have a headache. So there may be a subjective feature, then there's also what we can measure in a laboratory or otherwise, and that would be the rhythm of their sleeps through the night is not a natural one where they go into deep sleep and then they go into dream sleep and they go into other phases of sleep through the night. Then that could have more physical factors that we may not immediately notice, but it might have a subtle impact upon the attention or our ability to retrieve information the next day and only when we're really measuring it, with technical kind of testing, would we pick that up. So sleep, poor sleep or good sleep. It's both subjective, but it also has an objective kind of measurable effect that we can dig into.

Chin: Well then knowing how important sleep is, what can contribute to poor sleep?

Barczi: There's a long, long list of things, but try to summarize in broad categories. We know that if a person has a lot of stress in their life, there's a lot of emotional things going on in their life, then their mind can become very active. And sometimes it's hard to turn their mind off when they put their head on the pillow at night, and so there's a lot of events in the day that can set us up for a poor night's sleep. There might also be activities or habits that we do that could be maladaptive for sleep. So drinking cup of coffee right before bedtime for some people can be a problem, or taking in alcohol before bedtime. You might think that taking in alcohol helps people to fall asleep and in a certain percentage of people that's true, but as we metabolize and get rid of the alcohol through the night, most of us would endorse that our sleep is more disrupted. So although it might help the fall asleep, it's certainly does not help to stay asleep. There are many different health problems that can contribute to poor sleep. So anyone who's having any kind of pain, chronic pain or might have breathing difficulties, shortness of breath from a heart problem, or might have difficulties with other things like high blood sugar is causing a person to have to run to and from the bathroom during the night.  So these are all examples of medical conditions that can interfere with sleep quality if we keep moving along. Many of the medications that we prescribe for some of these issues can sometimes have a negative effect on sleep, so many medicines that might influence our ability to be alert or they may activate our brain would be good, except if they're taken somewhere close to bedtime. Then there are a number of psychiatric or psychological factors. So I mentioned stress, but more specifically things like depression and anxiety. In the veterans population, post traumatic stress disorder. These are examples of conditions that will also have very specific ways they disrupt sleep. Then we finally get to a list of some of what I call the primary sleep disorders, and so that's usually what people think of first. But I want to emphasize that those other things that I've mentioned just previously can oftentimes be much more common and much bigger deal, but there are a number of different distinct sleep disorders. Some of the more common ones involve sleep breathing. And a common sleep breathing disorder, is something we call sleep apnea. And sleep apnea in a simple sentence, sleep apnea is recurring pattern of stopping breathing or under breathing, which then causes the oxygen level in our body to dip down and it also causes our body to get all charged up because, no surprise, the body does not like holding its breath or not getting oxygen. There are also a series of different nighttime movement disorders, probably the most common and might be familiar to the general population, restless legs syndrome, and that's a hard thing to describe, but if someone's ever had it, they know. But then there's another condition called periodic limb movements asleep which happens to be our muscles and our legs want to twitch or jerk and when they twitch or jerk, sometimes they can wake our brain up also. So this is by no means a complete list, but this describes some of the common phenomenon that can interfere with our ability to sleep. I want to make one last comment and it has to do with sleep as a biological rhythm. So people may have heard the term circadian rhythm, and circadian rhythm means that it's a biological rhythm that's coordinated in the body to happen in a certain fashion day after day after day, and our body tries to maintain regularity or rhythm in what it does, including going to sleep at the same time and waking up at the same time every day. There are various things that can influence the circadian rhythms. Everyone who's ever gotten on a plane and gone halfway across the world has experienced jet lag. That's a form of a circadian disturbance. But our bodies can change as we age and sometimes those internal clocks that help coordinate these rhythms can become desynchronized and we're now learning that with that desynchrony in that internal clock that may also contribute to actually important brain changes and sleep changes that might relate to dementia.

Chin: Wow. In my clinic, a lot of people ask how much sleep should they be getting, and I know that as we get older, our sleep patterns can change. What do you say to patients?

Barczi: So first off, there's a population curve, meaning that if you look at a whole bunch of people in the population, you'll find people who are short sleepers. These are individuals now that may still need six and a half hours of sleep, but six to six and a half hours of sleep is more than ample for them to feel regenerated and we don't see that they have a sleep debt afterwards. We can measure that with certain types of testing. On the other hand, there are some poor unfortunate souls out there who literally 10 or 11 hours of sleep or they will feel exhausted and tired and not with it. Because it's a bell shaped curve, meaning you know there's a peak in the middle. Most of us probably need somewhere around seven to eight hours of sleep. But as far as meeting one's needs, the basic, most simple way to figure out if you're meeting your sleep need is are you experiencing tiredness the next day? Now, assuming you don't have a sleep disorder, you may just not be getting enough sleep for your body, and so if you're finding that on weekends you sleep in, you sleep longer and you feel better than you are in sleep debt, and that can be very important because when we start talking about individuals with health problems like those with memory, illness or dementia, if they are in sleep debt, their emotional state may be more labile. They may be more prone to act out or say things or do things that they might not normally do. If they're not as attentive than they may be more prone to fall or have events happen. If they're not as mentally sharp then if their memories are already challenged, pulling up information or learning new information can be even more difficult. So you could see how sleep would be very important for someone who might be at risk for a memory illness or who might be experiencing a dementia.

Chin: Well, I want to thank you again for joining us on Dementia Matters. We hope to have you back in the future.

Barczi: Thank you, Nate.

Credits: Dementia Matters is brought to you by the Wisconsin Alzheimer's Disease Research Center. The Wisconsin Alzheimer's Disease Research Center combines academic, clinical, and research expertise from the University of Wisconsin School of Medicine and Public Health, and the Geriatric Research Education and Clinical Center of the William S. Middleton Memorial Veterans Hospital in Madison, Wisconsin. It receives funding from private, university, state, and national sources, including a grant from the National Institutes of Health for Alzheimer's Disease Centers. This episode was produced by Rebecca Wasieleski and recorded and edited by Alex Wehrli. Our musical jingle is "Cases to Rest," by Blue Dot Sessions. Check out our website at adrc.wisc.edu. You can also follow us on Twitter and Facebook. If you have any questions or comments, email us at dementiamatters@medicine.wisc.edu. Thanks for listening.