What Is the Relationship Between Sleep, Respiratory Health Among Adolescents?

The impact of impaired sleep, which is more frequent among adolescents, was associated with a greater risk of asthma and allergies among this age group, but association does not equal causation. As a result, these associations warrant greater investigation, as well as the potential effects of social determinants of health such as race and socioeconomic status, said Lakiea Wright, MD, practicing physician at Brigham and Women's Hospital in Boston and the medical director at Thermo Fisher Scientific.

Transcript

AJMC®: Hello, I'm Matthew Gavidia. Today on the MJH Life Sciences’ Medical World News, The American Journal of Managed Care® is pleased to welcome Dr Lakiea Wright, a practicing physician at Brigham and Women's Hospital in Boston and the medical director at Thermo Fisher Scientific. Can you just introduce yourself and tell us a little bit about your work?

Wright: Thank you! Again, my name is Dr. Lakeia Wright. I'm a board certified allergist, immunologist and also have board certification in internal medicine. For my work, I am a full time medical director at Thermo Fisher in the amino diagnostics division, so that's allergy and autoimmune testing. So, I speak to the clinical relevance of that and then I also see patients part time.

AJMC®:Sleep duration and quality among adolescents and teens has become a growing issue in recent years due to issues such as technology usage and even early school start times. What implications does impaired sleep have on teens, and how may they be affected differently compared with adults?

Wright: Yes, you know the Sleep Foundation describes sleep as a sort of food for the brain and based on studies, inadequate sleep can impact your mood, your performance, your ability to concentrate, and even your immune system. So, teens, according to the academy of sleep, need about 8 to 10 hours of sleep.

Adolescents do tend to trend towards later sleep times and later wake up times, but adequate sleep is essential for your health. With teens still actively growing and developing, it's really important. It's important for adults, but especially for teens too because they're actively growing and developing.

AJMC®: Can you explain why the prevalence of asthma and allergic diseases is increasing among children and adolescents?

Wright: So, we think that this reason may be multifactorial. When we think about asthma, we think about things like air pollution playing a key role, also exposure to environmental allergens. We see also with climate change these swings in climate, these warmer climates, that the pollen season can go a little longer and the pollen appears to be more potent sort of year by year with patients reporting more sort of intense symptoms and then symptoms that are lasting longer, so it's likely multifactorial.

AJMC®: In study findings published in ERJ Open Research, teens who prefer to stay up late and wake later were associated with a greater risk of asthma and allergies. Can you explain these findings, especially the relationship between sleep and respiratory health?

Wright: Yes, so, an association does not equal causation. We know that the development of asthma is multifactorial with environmental exposures playing a huge role. We have allergens on the one hand like the pollens I mentioned, but then things like dust mites, cockroaches, mold, even animal dander from our pets. I mentioned air pollution, diet, we have family history of environmental tobacco, smoke exposure.

Some of these risk factors were controlled for, like the pet dander and the family history and then the environmental smoke exposure, but not all of them were controlled for this study. So, again, that relationship between sleep and asthma is an important one to examine, but it's not well established as a risk factor. We know that there is nocturnal asthma, and this is well established and likely explained by the body having sort of decreased levels of cortisol at night. Since your natural steroid production goes down, then your asthma may flare that may cause more inflammation in the lungs. So, that is 1 of sort of the mechanisms that's well established when it comes to sort of sleep and nocturnal asthma–sort of the pathophysiology of it all.

We know that there's association, which is not as well studied between sleep disordered breathing, which can range from snoring to obstructive sleep apnea and asthma–moderate to severe asthma, there's an association there.

In this study, I don't think they sort of investigated or didn’t highlight snoring or that potential for some sort of sleep disordered breathing. In the literature now, we can see that with sleep disordered breathing that upper airway inflammation and the lower airway inflammation of asthma, they're sort of bi-directional inflammation that can lead to worsening respiratory symptoms.

So, with this topic of later sleep time as a risk factor for asthma, we will need to investigate it a little bit more to sort of figure out what could be going on there and sort of control for the well known risk factors in a more robust way to see if we could pull out how strong this association is and also replicate it in other populations as this study is coming out of India.

AJMC®: Just to build off that, I know you just pointed out that the study findings are from India–are these findings applicable to the general population of teens? Are there increased risk levels based on sex or social determinants of health such as race or location?

Wright: Yes, so that's a very important factor which I'm very passionate about. Asthma disparities–sort of looking at the social determinants of health and race to sort of tease apart what could be underlying here to sort of affect change and to pinpoint how we can make a difference.

So, I would say that these findings are not generalizable at this point, because again, association does not equal causation and there are many factors including sociodemographic factors, for example, you mentioned sex and race.

As far as sex, they did control for that in this study. We do see some differences, with regards to sex in the US where boys are more likely to sort of have asthma and then sort of grow out of it, and then females may have a tendency to sort of hold on to the asthma. When I say grow out of it, it means sort of the asthma goes a little quiescent. Then, we do see studies where females are getting adult onset asthma perhaps at a higher rate. So, there are differences in sex here.

Then when we look at race in the United States, we see racial health disparities in regards to asthma. We see that people of African ancestry, they’re African American or self identifying as black or Puerto Rican, we see that they have a higher prevalence of asthma, as well as higher morbidity and mortality. So, if you look at stats for black Americans compared to whites, or people who self identify as black, we see that they are 3 times more likely to die of asthma. So, we see those racial disparities there.

So that's really important to take into consideration when we're trying to sort of generalize things, we have to look for those sort of racial and ethnic differences, because they may exist as we see them here in the United States.

Then, also, when we're talking about sociodemographics, we also have to consider the socioeconomic status. As part of those social determinants of health it can also affect sort of this relationship between prevalence, morbidity, and mortality with regards to asthma. So, we see here that lower income individuals in both urban and rural communities have higher prevalence, as well as morbidity and mortality, and then often link to the social determinants of health.

We know that the social determinants of health are very important with access to care and education, and even food. There were some studies, which I participated in 1 study, where we looked at–of course, association doesn't need causation, but we looked at the amount of sugar intake and risk of asthma development and we saw that higher sugar intake compared to lower sugar intake actually correlated with a higher or greater odds of developing asthma.

So there's so many risk factors, and especially when we look at housing conditions, substandard housing conditions–with those sort of conditions, you often have a greater likelihood of exposures to allergens like mouse and cockroach, which can also influence the development of asthma. So, even though I cited a lot of US based data, we also see that in other parts of the world we see this correlation between lower socioeconomic status and asthma, but of course in the US, we have a lot of data regarding this phenomenon.

AJMC®: I know you just touched on this, but how can these study findings warrant greater research into teen sleep and respiratory health? And what data is still needed to better understand this relationship?

Wright: So, I think that this is a very important topic. Further investigating sleep timing and asthma or duration of sleep and sleep activity–sleep quality, that's very important in asthma and it's an area that's sort of not as well developed as some of the sort of other areas. So I think it's an important topic, and it's very intriguing, but we need to tease apart that potential, plausible mechanism.

The authors did cite melatonin in relation to asthma, but that's not sort of well established. Not many studies are investigating that. So, we would need to see more of those studies, perhaps in mouse models that they can cite to see what is the pathobiology? What is the relationship between sleep, timing of sleep, and quality of sleep with the development of asthma, and how that relates to the inflammation of asthma.

So, we just need to sort of have more information that further investigates that. Then, I mentioned the mouse studies, but also, of course, in humans, we would need to see some sort of biomarker–something to strengthen that association that's based on or gets at the pathophysiology or sort of the causation. We need to further develop that and perhaps a biomarker could serve as that bridge.

AJMC®: Lastly, do you have any other concluding thoughts?

Wright: Yes, so I would say that asthma is a very complex disease with many risk factors that can intermingle. We see this classic paradigm of sort of the Atopic March where kids who have eczema and food allergies then go on to have allergic rhinitis and asthma. There aren’t very many primary prevention methods so it's very important to sort of continue to study those risk factors so that we can come up with whether it's behavioral interventions or pharmacological interventions. Especially as a backdrop that we do see a rise or we are seeing a rise in asthma and allergies and we have to continue to acknowledge the importance of the allergic sort of backdrop in which it happens, especially with children and adolescents.

Up to 80% of their asthma can be allergic and so when we talk about sort of trying to stop that progression. On that Atopic March, 1 of the primary prevention methods is allergy shots, which sort of retrains that immune system. You have to know testing, whether it's skin testing or blood testing, to sort of look at what's going on, whatever they're allergic to, and then when it's appropriate, you could put them on allergy shots if they're at the point of sort of allergic rhinitis to try to prevent them from going on to asthma.

So, I think that's also important to note, while we're looking at risk factors, also looking at how can we change things and there are ongoing studies now to look at–sort of primary prevention as well. So, it’s a very exciting time.

AJMC®: To learn more, visit our website at ajmc.com. I’m Matthew Gavidia, thanks for joining us!