EP136: Unlocking Wellness One Night at a Time: Dr. Won Explains Sleep's Impact

Understanding Sleep with Dr. Christine Won: Importance, Disorders, and Practical Tips

In this episode, Christine welcomes Dr. Christine Won, an Associate Professor of Medicine at Yale University and a leading expert in sleep medicine. Dr. Won shares insights on how sleep disorders uniquely affect women, the importance of sleep, common misconceptions about sleep deprivation, and practical strategies for mitigating fatigue. They explore the differences in individual sleep needs, the potential inaccuracies of consumer sleep tracking devices, and the impact of sleep on emotional regulation. Dr. Won also discusses sleep disorder symptoms, the influence of hormonal changes on women's sleep, and provides tips for healthcare professionals dealing with sleep deprivation. Listeners will gain a deeper understanding of how to prioritize sleep for better health and productivity.

00:00 Introduction and Guest Welcome

01:15 The Importance of Sleep and Misconceptions

03:00 Understanding Personal Sleep Needs

04:30 Wearable Devices and Sleep Tracking

06:35 Stages of Sleep Explained

10:44 Sleep and Emotional Regulation

11:44 Challenges in Medical Training and Sleep

13:05 Fatigue Mitigation Strategies

16:28 Sleep Disorders in Women

20:18 Signs of Poor Sleep Health

22:31 Final Thoughts and Conclusion

Transcript

Christine Ko: [00:00:00] Welcome to today's episode. I'm thrilled to have Dr. Christine Won with us. Dr. Won is an Associate Professor of Medicine at Yale University in the section of Pulmonary Critical Care and Sleep Medicine. She serves as the Medical Director of the Yale Centers for Sleep Medicine and the Director of the Yale Women's Sleep Health Program. As a leading expert in sleep medicine, Dr. Won's research and clinical work focus on complex sleep disorders, with a special emphasis on how sleep disorders uniquely affect women. Dr. Won's background includes her time at Stanford University, where she completed both her undergraduate education, and her advanced training in sleep, pulmonary, and critical care medicine. She has been actively involved in advancing telemedicine for sleep health, and she served in leadership roles, including as past President of the Society of Anesthesia and Sleep Medicine. I'm so pleased to have her here today to talk about sleep basics everyone should know [00:01:00] and how quality sleep plays a crucial role in optimizing our health, energy and emotional well being.

Welcome to Dr. Won. Welcome to Christine.

Christine Won: Hi, how are you? Thank you for having me. I'm so excited to be here.

Christine Ko: Thank you for being here. So I'm going to first ask you why, especially I think in medicine circles, healthcare circles, a lot of us still treat sleep deprivation as a badge of honor, even though we know that we need our sleep. Why do you think that is?

Christine Won: We live in an intense society where productivity is so valued. And so we feel what we do with our time awake trumps, or is more important than, paying attention to our physiology and to our biology, not really looking at sort of long-term consequences or even how sleeping could be helpful in your productivity. It's just a lot of misunderstanding about, the utility of sleep, not [00:02:00] really understanding its function. In this current society, we're so pressured to be productive, especially as physicians. So sometimes sleep is interpreted as something that sort of gets in the way of our productivity. The mentality is still, sleep is a waste of my time. I should stay awake as much as I can to do more, get more product out. When in fact, we sleep one third of our lives. There's a purpose to sleep. 

Christine Ko: Wow. I've never really thought about it that way, that we sleep one third of our lives. Yeah, I feel like I don't really prioritize sleep. I am someone who needs to sleep. Some people really say, and I think they're being honest, Oh, I only need four hours of sleep or five and I'm fine. But I definitely need at least seven to be like, happier, I think, seven hours. I can function for a couple of days, I feel like on less, but I'll be cranky. I think ideally I would get seven to eight. And that seems like that's what most people [00:03:00] need.

Christine Won: Yeah, the average amount of sleep that adults, healthy adults need per the National Sleep Foundation is between seven to eight hours, but it's a bell curve, and there's definitely variation from person to person about the right amount of sleep you need. There are definitely people who need eight, nine, 10 hours even, and there are people who their biological need for sleep is really on the shorter side, five and a half, six hours. I'm very envious of that. I tend to be a longer sleeper. What we have to do is just pay attention to how we feel after a certain hour of sleep, and determine what our personal sleep need is, and then aim to get that amount of sleep. That would be your functional sleep. There are definitely people out there who only need 6 or 7 hours of sleep. And that's great. But it's not for everyone. People say, Oh, yeah, I only need 5 or 6 hours of sleep, but I'm drinking a pot of coffee, and I'm grumpy, and I'm not really, paying attention to things I should [00:04:00] be, then that's really not your sleep need.

Christine Ko: So how can you figure out your sleep need? 

Christine Won: Making sleep a priority, definitely, and trying to sleep regular hours every night, and then seeing the quality of your sleep at night. So the depth of your sleep, but also how you feel when you wake up and how you function during the day. If you're just a little bit more attentive and attuned to how you feel, you might easily be able to tell, Oh yeah, I'm a seven, eight hour sleeper versus I'm a five, six hour sleeper versus I'm a nine, 10 hour sleeper. 

Christine Ko: Yeah. Christine and I are friends. I recently told her that I got an Oura ring, a wearable kind of device. She had some good advice for me on the Oura ring or really any wearable. Can you share that with everyone? 

Christine Won: Yeah, you were telling me how the ring was outputting sort of your sleep quality and telling you how many hours of sleep you're getting, what stage of sleep you're getting. I just cautioned you that these wearables, there's so many of them, wearables and nearables, [00:05:00] right? Like things that you don't actually put on your body, put next to your bed. They somehow measure your breathing, your heart rate, and calculate your sleeping, things like that. There are so many consumer products these days, and that's just speaks to our advanced technology as well as our understanding of sleep physiology. I just caution, people who do use those devices that they take it with a grain of salt because a lot of these devices are not FDA approved for any kind of medical decision making. Some of these devices aren't validated against real measurements. Just be cautious.

Christine Ko: Yeah. Okay. And so the gold standard would be like actually having a sleep study with someone like you, who's trained in sleep medicine. I go to like a sleep center, and I'm observed while I'm sleeping.

Christine Won: Yeah, technology that good, like diagnostics, medical grade, should be compared to gold standard, like a sleep laboratory measured sleep.

Christine Ko: I already know the wearable that I have is a little bit inaccurate because sometimes it thinks that I'm [00:06:00] sleeping, but I'm just watching TV. It'll say, you took a long time to fall asleep, my sleep latency, the time it takes me to go to sleep. Sometimes if I'm just sitting there, not even in bed, but I'm sitting in front of the TV, I guess I'm so inactive that it thinks I'm trying to sleep for that time. It'll say, Oh, you tried to fall asleep at 1030 and you didn't fall asleep until 1130. But I know that actually I was watching TV from 1030 to 1130. I get this data from the Oura ring, sleep latency, deep sleep, REM sleep, and light sleep. Can you talk about those things? 

Christine Won: Sure. Sleep latency refers to how long it takes you to fall asleep when you're trying to sleep. The longer your sleep latency, that just means it took you a long time to fall asleep. It's a useful metric to know if you're, for example, someone who suffers from insomnia and you want to [00:07:00] understand how bad is their insomnia. Are they up three hours at night trying to sleep or is it really 10 minutes and their perception is an hour or something? And that helps with treatment actually trying to address insomnia. That's sleep latency.

Deep sleep is our delta slow wave sleep. That's the stage of sleep that people are very heavily unresponsive. That's like the type of sleep children get; that child you can remove out of the car seat and carry up the stairs and wipe their face and put them in bed. They never wake up. They're likely in deep sleep or delta sleep. This stage of sleep is by these, you know, when we measure it on the EEG, these really big, slow waves, these Delta waves, we call it. This sleep is very important. It's the sleep that is predominant in the first half of the night. It's thought to be that restorative stage of sleep. That's the sleep where all the sort of chemicals and byproducts of your daytime function, metabolism [00:08:00] all are gotten rid of or recuperated during that sleep. That's the sleep that you're going to wake up, if you've got enough of that sleep, feeling pretty darn good. Alert. 

REM sleep is rapid eye movement sleep, and it tends to happen more in the second half of the night. It is that stage of sleep that is characterized by dreaming. It's actually a stage of your sleep where your brain is very active, and your brain is active presumably because it's processing a lot of the daytime memories that you've made. It's processing emotion. It's a very important part of sleep as well.

Christine Ko: Yeah. Going back to latency. The Oura ring told me that ideally I would have 20 minutes of sleep latency. That seems like a really long time.

Christine Won: Yes, so sleep latency. Really, it only matters in terms of how it affects you. So what I mean by that is if you're in bed and you're, you know, in a nice position and you're just reading or you're [00:09:00] closing your eyes, meditating, and it takes you an hour to fall asleep, but that doesn't bother you at all. Like you enjoy that part of your, um, time in bed. Then we don't call it a problem, even though technically your sleep latency is one hour. There's no need to intervene. There's nothing abnormal about it. We say, that's great. People on the contrary may just hit the bed and just fall asleep fall asleep like that, within seconds, right? Then their sleep latency is very short. It could be a manifestation of really very healthy sleep and regular sleep habits, that your body is just trained to turn off at a certain time. Or it could be an indication of some sleep deprivation. You're so tired, you just hit the bed and your body just needs to go to sleep. But even if it's short, it's not really a problem unless it's associated with something else like severe sleepiness during the day where, it's not just a short sleep latency during the night, but also during the day, you're dozing, falling asleep, can't keep awake. That's a sign of some level of sleepiness that should be addressed.

Christine Ko: [00:10:00] Okay, that's good. I do think you're right that sometimes when I fall asleep very quickly, it is because I'm overly tired. But sometimes actually when I'm overly tired, I actually can't fall asleep. It's like I'm overstimulated or something.

Christine Won: Yeah, that definitely can happen where you're so tired, your neural networks are a little bit confused, if you will, because you're probably fighting sleep all throughout the day. And then now you're going to bed and you're trying to turn that off and wind down and promote your sleep network. But, you just have too much adrenaline, too much, maybe irritation that you're so tired, things like that. In those cases, relaxation exercises like deep breathing, meditation, visualization, all these things help calm the brain and hopefully get you to sleep sooner. 

Christine Ko: Yeah. Sleep is so important for emotional regulation. Can you talk about that? It's totally true for me, but I would love to hear your take on it.

Christine Won: Yeah. Everyone anecdotally can attest to that, right? When we don't get a good night's sleep, we're all cranky, easily [00:11:00] triggered, not at our best, if you will. There definitely is a correlation between healthy sleep and mood and how you feel. From a research or scientific standpoint, that's been well shown. Sleep deprivation can lead to things like poor judgment, high risk taking, overestimation of threat, lack of empathy. It definitely plays a role in how we process emotions. That's really important for us as doctors in particular, because, we are, as a field, highly sleep deprived. But we have to deal with a lot of emotions related to people being ill. Difficult conversations, things like that. So empathy, emotional regulations. I think this is very important for us as a field.

Christine Ko: Yeah, and yet we definitely are sleep deprived, especially during training. 

Christine Won: Yeah. Like you said, it was a cultural thing where, the more we do the, it's the badge of honor. We don't really understand that it's putting people at risk actually, because we're not making our best [00:12:00] judgments and we're not making the best medical judgments.

Christine Ko: Yeah. Residents do have reduced work hours, like 80 hours per week. That still doesn't mean that they're necessarily sleeping enough. But I know that the old school generation is, oh, but the training isn't as good anymore because of a 80 hour work week cap. And yet I think the residents these days who have that cap still oftentimes feel like they're sleep deprived. And as you said, I think it does really affect patient care. And doctors being so sleep deprived and busy, patients know this doctor is tired, stressed out, maybe cranky. Is there any solution, do you think? 

Christine Won: Yeah, it's a tough call because our profession mandates these long hours, right? A hundred hours, 120 hours during training, that was totally normal, and sleep was definitely not valued.

The work restriction hours for our trainees. These are good measures. A lot of jobs require these vulnerable moments where we're sleep [00:13:00] deprived or not sleeping at the right time of day that make us perform less than we'd like to. One thing we can do besides reducing the work hours is fatigue mitigation strategies.

Christine Ko: What are some fatigue mitigation strategies? I've never heard of this. 

Christine Won: Yeah. Definitely one is ensuring that there's a good opportunity to sleep. Power naps, strategic caffeine use, the employer being sensitive to what kind of tasks at what part of the shift they're assigning to people. If you're a night shift worker, you wouldn't give someone a really difficult task at the end of their shift. You might give at the beginning of the shift, things like that. It is a lot of work, but I think the outcomes are beneficial for everyone. 

Christine Ko: Do power naps help?

Christine Won: Yeah, power naps are great. Speaking personally and then from a medical standpoint. Power naps are really a good idea to help with sleepiness during the day. We call them power naps because they're short [00:14:00] naps. They're on the shorter end, a 20 to 30 minute nap. That's just enough time to decrease some of that sleep drive, that sleep need, that sleep pressure, we call it. Just enough that you can function for a couple more hours. It's not a permanent solution by any means, but it's a good way to cope. A 20, 30 minute nap has shown to increase alertness by 50%. It lasts only two or three hours, but you'll get through two or three hours more.

Christine Ko: Okay. And when you said strategic caffeine, what does that mean? 

Christine Won: Caffeine is a reasonable tool to fight sleepiness. You don't want to be excessive about it. And you also build tolerance to it. So, you know, after a while might not be as effective. So you want to make sure you don't overdo it and you take some caffeine holidays because what happens is your brain has these receptors for caffeine that if you keep taking increasing doses then it's just going to upregulate the receptors. And so then the effect loses over [00:15:00] time. The effect of a cup of coffee, you might not feel it as much. So you want to give yourselves holidays so your receptors back off a little bit. And so the next time you drink coffee, then you're bright eyed.

It takes about 15, 30 minutes to kick in for most people. So if you're a night shift worker, for example, and you have a long drive home, and you're just going to be sleepy. You want to take maybe one cup 30 minutes before you get on the road. You don't want to be again, excessive about it. Cause then when you try to go home and you try to fall asleep, that might impair your sleep. The timing of your caffeine is one strategy. 

And then there's this exercise that we sometimes do. It works differently for different people, but you might take a cup of coffee, for example, like 200 milligrams of caffeine right before a power nap. Again, it might take you 15, 30 minutes to actually feel the effects. So you fall asleep, cause you're so tired. You have that high sleep pressure. You sleep 20, 30 minutes, you wake up, and the caffeine on top of that has kicked in. And so that gives you much more of an impact [00:16:00] of alertness. It also prevents what's called sleep inertia, that kind of dragging, like even more tired kind of sensation. It might mitigate that as well.

Christine Ko: That's cool. Even now with the reduced hour work week, I think people often do feel sleep deprived, and medicine is so hierarchical. You don't really have control over that. You can't just leave and say, I'm going to go take a nap now. Or just go home. But I guess you could probably try to do that strategic caffeine. 

Also, you focus on how sleep disorders affect women, and I think an additional problem for women, and it wasn't true for me because I had kids after my training, but I see residents who have kids during training. And then, even more, they're sleep deprived, because even when they're not working in the hospital, they might have to be taking care of the baby multiple times a night.

Christine Won: That is a very important point you're saying because it's not just work. It's life that gets in the way of [00:17:00] sleep, right? And no matter how much you want to prioritize that, your life just doesn't allow you. So that's when you sort of use those strategies of trying to nap and mitigate the caffeine use and things like that. 

The hormonal changes in our milestones in our life, like pregnancy and menopause, there's definitely sleep changes that occur related to that and specifically relates to hormones. So, during pregnancy, you have high progesterone levels and progesterone is known to be one of those sleep inducing kind of hormone. And then, even after you deliver, you have high levels oxytocin, which is like that hormone that helps you let down milk and all that and makes you feel you love your baby, fall in love with your baby, and all that. And that could be also sedating. That hormone could also be sedating as well. 

Just a little side story that I remember. I don't know how it was with you, Christine. But I am such a heavy sleeper. Nothing can wake me up. I was to a point where I got nervous I thought, oh gosh, you know once I have this baby, how am I gonna wake [00:18:00] up? I was nervous after I had my newborn, like am I gonna hear her? Am I gonna wake up? But I totally did and even before my husband who's a very light sleeper who wakes up to anything. Like I could just hear a little bit of movement and I would be right up. It was just so different than how I was sleeping before I had my daughter. I was just thinking, this has got to be not just psychological but I think this is physiological. There are studies that suggest that that is true. Women have a much lower arousal threshold. And it might be somehow related to this this parenting role, this motherhood role, that we need to be more sensitive to, specifically my baby waking me up, not anything else, not construction outside, but just my baby. 

Hormones are definitely impactful in your quality of sleep. Even during menstruation, your sleep changes. Before you ovulate, you tend to have much better sleep because of the hormones, and then you ovulate, and then you have less REM sleep, more disturbed [00:19:00] sleep.

So a lot of hormones that are important in the woman's life cycle are affecting our sleep. Menopause obviously is a different kind of problem. A lot of people who enter menopause suffer from insomnia, not able to fall asleep, a lot of fragmented sleep. It could be related to many things. Vasomotor symptoms like hot flashes, night sweats, those are important things. But even just the hormonal changes probably change the sleep depth and quality. 

Christine Ko: Yeah, I agree with you. There's something different. I would wake up definitely much more easily when my kids were babies. I definitely felt like being a new mom was torture. Because of the sleep thing, I was so tired. I'm really envious of parents who are like, Oh, the baby's four weeks old and already sleeping like five hours. My first kid didn't sleep straight for 2. 5 years. So for 2. 5 years, I had bad sleep. I wasn't proud of it. I didn't wear it as a badge of honor. I felt really tortured by [00:20:00] it. I would do things like you said, take naps when I can. But I think at the same time when you work a lot, I did work a lot back then, it's really hard to get enough sleep. 

Christine Won: If anyone doubts the importance of sleep, they should be a new mother. 

Christine Ko: Yes, absolutely. So I think you already mentioned some of the signs of poor sleep health. You said being cranky. Sometimes it's not being able to fall asleep quickly, but sometimes it's being able to fall asleep quickly. Are there any signs that are really overlooked that people don't really think about? 

Christine Won: There's two ways to think about it. One is how do you sleep at night in terms of, do you wake up a lot? Do you feel like your sleep is light and shallow? Like, you can hear things and easily awoken. And then there's like the daytime stuff. Like, how do you feel during the day? How do you feel when you wake up? How do you function during the day?

Do you have a propensity to like doze when you're in a quiet room, dark room, things like that. And these should be alerting signs. I, I [00:21:00] would definitely first check. Am I getting enough sleep? That's usually the most common problem is people not getting enough sleep. And then secondly, I would say, am I getting regular sleep?

Cause it's actually important, the timing of your sleep. So making sure you're not doing big changes in your sleep schedule and then sort of entertain other ideas of why you're not sleeping well. 

Christine Ko: Yeah. When you are in training and you have this schedule that's set for you so you can't necessarily sleep on a regular schedule. Do you have recommendations on what to do then? 

Christine Won: A lot of things are changing. The field of medicine and the people who are leading education and training are more sympathetic and understanding and knowledgeable about the importance of sleep to the trainees. A lot of the educators work with me in terms of trying to promote sleep to their trainees. It's not a hard sell. So if somebody has to get their schedule changed or reduced, I think people understand. It's obviously a balance. There's probably going to be some [00:22:00] level of tiredness, sleepiness, sleep deprivation. But to a point, you just have to sort of understand where is that sweet spot where it's not impairing you. Not just your ability to take care of a patient or do a task, the well being of the trainee as well. You want them to not burn out. You want them to have resilience and go on and things like that. 

Christine Ko: Yeah, that's good advice. I think you're basically saying to ask, right?

Christine Won: Talk to supervisor. I don't think it's ignored as much anymore. Yeah. 

Christine Ko: Do you have any final thoughts?

Christine Won: No. Get some sleep. 

Christine Ko: Okay. Thank you so much for doing this with me. I really appreciate it. 

Christine Won: Yeah, it was so much fun. Thank you for having me, Christine.