Adolescent Sleep

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March 5, 2017 – MCAT CARS Passage

Question: What is your summary of the author’s main ideas. Post your own answer in the comments before reading those made by others.

A new study from the University of Alabama at Birmingham indicates that adolescents who experience sleep problems and longer sleep duration are more reactive to stress, which could contribute to academic, behavioral and health issues.

Existing studies show that nearly 70 percent of U.S. adolescents do not receive sufficient sleep. It is also known that insufficient sleep and sleep problems contribute to cognitive problems and poor physical health over time, possibly because of disruptions in a key part of the neuroendocrine system that controls reactions to stress and regulates many body processes — the hypothalamic-pituitary-adrenal axis, or the HPA axis.

The relationship between sleep and the HPA axis has been studied in both children and adults; but little is known about this link during adolescence, which is a key period of time, as both sleep and the HPA axis are undergoing significant developmental changes related to puberty.

Sylvie Mrug, a psychology professor in UAB’s College of Arts and Sciences, and her colleagues from UAB and Arizona State University sought to further explore the relationship between sleep and reactivity to stress, specifically as it relates to HPA-axis activity, in adolescents.

The researchers examined two dimensions of sleep — sleep duration and sleep problems from the perspectives of adolescents and their parents, as well as cortisol levels before and after social stress. The team also looked at how the results varied based on gender.

“We chose to look at sleep patterns in urban African-American adolescents, due to information we understood from earlier research in the field,” Mrug said. “This particular population is more likely to experience insufficient sleep, and their functioning is more negatively affected by lower sleep quality, so we knew that finding results for this demographic could be especially important.”

Eighty-four adolescents with an average age of approximately 13 took part in the study. During their visit to the research lab, participating adolescents were given the children’s version of a common stress test, called the Trier Social Stress Test, to measure their physiological responses to stress. This test involves speaking and computing mental math problems in front of an audience. Saliva samples were taken from each participant in order to test cortisol levels before and after the stress test.

Participants then reported on their bed times and wake times and any sleep problems, such as insomnia, daytime sleepiness and general sleep quality, during a regular week. Parents of the adolescents were asked to report on their children’s sleep as well.

The adolescents most commonly reported the following sleep problems: the need for multiple reminders to get up in the morning, not having a good night’s sleep, feeling tired or sleepy during the day, and not being satisfied with their sleep.

The researchers looked at the cortisol levels of the adolescent participants. Cortisol release during and after the stressful lab test was higher for adolescents who reported more sleep problems and longer sleep duration, and whose parents reported longer sleep duration.

“The result of higher cortisol levels in adolescents experiencing sleep problems was exactly what we expected to see,” Mrug said. “We were, however, surprised that longer sleep duration predicted a stronger cortisol response, because previous studies linked shorter sleep duration with higher cortisol levels. Generally, less sleep is related to poor outcomes, not the other way around. In this case, this unexpected result could be explained by considering that longer sleep duration does not necessarily reflect higher-quality sleep, but instead may serve as another indicator of sleep problems, at least among urban adolescents.”

The effects of sleep problems on greater cortisol release during stress were stronger in females than in males, suggesting that adolescent girls may be more sensitive to disrupted and poor quality sleep.

“Overall, the results of our study confirm what we originally hypothesized — that sleep problems induce greater response to stress in adolescents,” Mrug said. “It’s important that we know this, because the enhanced and prolonged activation of the HPA axis in response to stress could contribute to more health problems. The urban African-American youth whom we studied may be particularly negatively affected by poor sleep because they are more likely to experience uncontrollable stress related to community and school violence. We want to do all that we can to understand ways we can help ensure better cognitive, emotional and physical health outcomes for these adolescents.”

Adapted from sciencedaily

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This was an article on Population Health.

Have a great day.
Jack Westin
MCAT CARS Instructor.
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36 Comments


  1. MI: more sleep problems = more cortisol

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  2. The importance of sleep patterns (duration and dispruptions) on behavior. Bad sleep habits = bad social reactions (high stress)

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  3. Sleep problems and long duration of sleep results in higher cortisol” contrary to previous research

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  4. Surprisingly longer sleep duration correlated with more stress. Researchers believe that sleep quality is more important than duration.

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  5. More sleep + More sleep problems leads to higher reactivity to stress. Reevaluate more sleep for adolescents (not kid not adult) claim.

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  6. Higher sleep problems is related to higher stress hormone levels in adolescents, and specially more in females than in males.

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  7. sleep duration and problems affect stress responses in African American adolescence

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  8. MIP: high sleep problems in adolescents = high stress levels = high activation HPA (Mrug)

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  9. Researchers have shown in a single study of African-American urban teenagers that poor sleep (of any duration) leads to a higher stress response as measured by serum cortisol levels. Higher stress (serum cortisol) plays an important role in a host of other health problems.

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  10. higher sleep probs = higher stress and other issues (in African American youth) (Mrug)

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  11. Sleep problems in adolescents (esp African-American) causes more stress (Mrug)
    Study proved that high cortisol = more sleep problem & longer sleep duration

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  12. MI: up sleep prob=up cortisol in AA adols (increased risk to sleep probs)
    tone: neut

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  13. Sleep issues=bad: ^ stress response

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  14. sleep problems + longer sleep = high stress + HPA problems
    neutral tone

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  15. MI: Sleep problems, like too much or too little = Increased stressed in Adolescents

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  16. not enough known, sleep problems = increased cortisol

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  17. Less sleep=stress=less cognition
    study shows increased sleep duration unexpectedly increases cortisol + could reflect poor sleep quality

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  18. Sleep problem + increase sleep duration = increased stress + cognitive and health problems in adolescents due to prolonged and enhanced activation of their HPA axis

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  19. Sleep problems + longer sleep = prone to stress + increased level of cortisol (may be due to lower quality of sleep).

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  20. stress=sleep problems+long sleep, stress=High cortisol

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  21. poor sleep —-> stress + cognitive dysfunction in urban adolescents, HPA likely involved

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  22. Sleep problem in adolescence affects mental functioning. Authors tone is favaorable with great emphasis on ways to finding solutions to end sleep problems

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  23. long duration of sleep = high cortisol levels; more research must be done to find proper relations between sleep and HPA axis

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  24. More sleep problems = more cortisol

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  25. sleep problems and long sleep duration increase reactivity to stress in adolescents

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  26. Sleep prob= Increased stress response + important to know for AA youth

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  27. Sleep problems = increase stress/cortisol ; long sleep =/= good sleep quality

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  28. sleep problems + longer sleep negatively affect cognitive development + reactivity to stress in adolescents via HPA system (increased cortisol)

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  29. MIP: Sleep issues = inc stress
    Tone: Neutral

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  30. MIP: sleep problems = ^ stress response –>health problems

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  31. MIP: sleep problems/longer sleep –> stress; tone = neutral

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  32. MIP: sleep problems lead to stress in adolescents.

    Reply

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