Being surrounded by green space in childhood may improve mental health of adults
February 26, 2019
Science Daily/Aarhus University
Children who grow up with greener surroundings have up to 55 percent less risk of developing various mental disorders later in life. This is shown by a new study emphasizing the need for designing green and healthy cities for the future.
A larger and larger share of the world's population now lives in cities and WHO estimates that more than 450 millions of the global human population suffer from a mental disorder. A number that is expected to increase.
Now, based on satellite data from 1985 to 2013, researchers from Aarhus University have mapped the presence of green space around the childhood homes of almost one million Danes and compared this data with the risk of developing one of 16 different mental disorders later in life.
The study, which is published today in the Journal PNAS, shows that children surrounded by the high amounts of green space in childhood have up to a 55% lower risk of developing a mental disorder -- even after adjusting for other known risk factors such as socio-economic status, urbanization, and the family history of mental disorders.
The entire childhood must be green
Postdoc Kristine Engemann from Department of Bioscience and the National Centre for Register-based Research at Aarhus University, who spearheaded the study, says: "Our data is unique. We have had the opportunity to use a massive amount of data from Danish registers of, among other things, residential location and disease diagnoses and compare it with satellite images revealing the extent of green space surrounding each individual when growing up."
Researchers know that, for example, noise, air pollution, infections and poor socio-economic conditions increase the risk of developing a mental disorder. Conversely, other studies have shown that more green space in the local area creates greater social cohesion and increases people's physical activity level and that it can improve children's cognitive development. These are all factors that may have an impact on people's mental health.
"With our dataset, we show that the risk of developing a mental disorder decreases incrementally the longer you have been surrounded by green space from birth and up to the age of 10. Green space throughout childhood is therefore extremely important," Kristine Engemann explains.
Green and healthy cities
As the researchers adjusted for other known risk factors of developing a mental disorder, they see their findings as a robust indication of a close relationship between green space, urban life, and mental disorders.
Kristine Engemann says: "There is increasing evidence that the natural environment plays a larger role for mental health than previously thought. Our study is important in giving us a better understanding of its importance across the broader population."
This knowledge has important implications for sustainable urban planning. Not least because a larger and larger proportion of the world's population lives in cities.
"The coupling between mental health and access to green space in your local area is something that should be considered even more in urban planning to ensure greener and healthier cities and improve mental health of urban residents in the future," adds co-author Professor Jens-Christian Svenning from the Department of Bioscience, Aarhus University.
https://www.sciencedaily.com/releases/2019/02/190226112426.htm
Split and continuous sleep in teens impact cognition and glucose levels differently
February 22, 2019
Science Daily/Duke-NUS Medical School
Under conditions of insufficient sleep, effects on cognitive performance and morning glucose levels vary depending on how sleep is distributed.
Many adolescent students sleep less than the recommended duration of 8-10 hours a night. It is unclear; however, whether short night sleep combined with an afternoon nap is as good as having the same amount of sleep continuously during the night without a nap. Researchers at Duke-NUS Medical School have demonstrated for the first time that different sleep schedules with the same total sleep opportunity over 24 hours may have dissimilar effects on cognition and glucose levels. This is the first study to gather experimental evidence on the notion that 'what may be appropriate sleep for one health goal may not be for another'.
The handful of studies that examined split sleep schedules with normal total sleep duration in working-age adults found that both schedules yield comparable brain performance. However, no study has looked at the impact of such schedules on brain function and glucose levels together, especially when total sleep is shorter than optimal. The latter is important because of links between short sleep and risk for diabetes.
The researchers measured cognitive performance and glucose levels following a standardized load in students, aged 15-19 years, during two simulated school weeks with short sleep on school days and recovery sleep on weekends. On school days, these students received either continuous sleep of 6.5 hours at night or split sleep (night sleep of 5 hours plus a 1.5-hour afternoon nap).
"We undertook this study after students who were advised on good sleep habits asked if they could split up their sleep across the day and night, instead of having a main sleep period at night," said Prof. Michael Chee, Director of the Centre for Cognitive Neuroscience, Professor of Neuroscience and Behavioral Disorders Programme, Duke-NUS Medical School and one of the study's senior authors. "We found that compared to being able to sleep 9 hours a night, having only 6.5 hours to sleep in 24 hours degrades performance and mood. Interestingly, under conditions of sleep restriction, students in the split sleep group exhibited better alertness, vigilance, working memory and mood than their counterparts who slept 6.5 hours continuously. This finding is remarkable as the measured total sleep duration over 24 hours was actually less in the former group," Prof. Chee added.
However, for glucose tolerance, the continuous schedule appeared to be better. "While 6.5 hours of night sleep did not affect glucose levels, the split sleep group demonstrated a greater increase in blood glucose levels to the standardized glucose load in both simulated school weeks," noted Dr. Joshua Gooley, Associate Professor of Neuroscience and Behavioral Disorders Programme, Principal Investigator at the Centre for Cognitive Neuroscience, Duke-NUS Medical School and the senior co-author of this study.
Although further studies are necessary to see if this finding translates to a higher risk of diabetes later in life, the current findings indicate that beyond sleep duration, different sleep schedules can affect different facets of health and function in directions that are not immediately clear.
Professor Patrick Casey, Senior Vice Dean of Research, Duke-NUS Medical School, commented, "Recent sleep surveys show that Singaporeans are among the world's most sleep deprived people. This is the latest in a series of studies from a team of researchers from the Neuroscience and Behavioural Disorders Programme and Centre for Cognitive Neuroscience that have provided valuable insights into the importance of good sleep."
https://www.sciencedaily.com/releases/2019/02/190222101312.htm
Student likeability might be link between academic success and risk of depression
Children struggling in elementary school are less liked by their teachers and peers, opening them up to higher risk of depression
February 21, 2019
Science Daily/University of Missouri-Columbia
A new study suggests that children doing well in classrooms are more popular and emotionally secure than their peers who are having trouble academically.
The research from the University of Missouri directly challenges the common stereotype that academically gifted children are considered less popular than their peers. The findings also confirm the significant impact academic performance can have on a student's mental and social well-being.
"Plenty of research before this study has shown that children who struggle in elementary school are more likely to experience feelings of frustration and worthlessness, which can put them at greater risk for depression," said Keith Herman, a professor in the MU College of Education. "Now we're finding that there is a link, with clues that a child's social life can be impacted by their success in class."
Herman's team studied 380 elementary school children and their teachers to examine how early academic struggles can lead to future depressive symptoms. Teachers in first and second grade rated how well-liked a student seemed to be by their peers. Findings from the study indicated that academic problems in first grade led to lower levels of likeability in second grade, which in turn predicted depression in third grade.
Herman says teachers and students can use this knowledge to find ways to help students address academic and social challenges before they have a lasting negative impact. He suggests that teachers and parents be wary of any subtle messages and judgements they might be sending to children who are experiencing troubles in class or with peers, while finding ways to identify and help children experiencing difficulties with math and reading.
"Teachers and parents should also think about giving as much encouragement and positive attention to children on other areas in which they excel," Herman said. "Maybe they struggle with math, but they excel at art. If a child feels like their passions and talents are valued, they are more likely to have a positive outlook on their self-worth."
https://www.sciencedaily.com/releases/2019/02/190221095113.htm
Study affirms self-reported sleep duration as a useful health measure in children
Results show agreement between sleep measures reported by children and their parents
February 14, 2019
Science Daily/American Academy of Sleep Medicine
While sleep questionnaires are commonly completed by children and their parents, there has been a lack of data comparing the validity of these self-reported sleep parameters. A new study indicates that these sleep characteristics are relatively accurate compared to one another, and they vary only slightly from objective sleep measures.
Results show that when compared with objective sleep characteristics recorded during overnight polysomnography, there was strong agreement between both child report and parent report: Children overestimated their sleep duration by a median of 32 minutes, and parents overestimated their child's sleep duration by 36 minutes. Similarly, children overestimated the time it took them to fall asleep -- known as "sleep latency"- by four minutes, and parents overestimated their child's sleep latency by two minutes.
According to the authors, similar variances have been found in previous studies that used actigraphy to estimate sleep parameters in comparison with overnight polysomnography. In prior research, adults also have been found to overestimate their own sleep duration.
"Simple sleep measures such as sleep duration have been shown to be important predictors of health in children and adults," said Dr. Daniel Combs, lead author and assistant professor of pediatrics at the University of Arizona College of Medicine -- Tucson and Banner -- University Medical Center Tucson. "Our results suggest that while not perfect, parent or child report of sleep is a useful and very inexpensive tool to measure sleep in children."
The study results are published in the Jan. 15 issue of the Journal of Clinical Sleep Medicine.
The study involved 285 children in the Tucson Children's Assessment of Sleep Apnea community cohort study. They ranged in age from about 9 to 17 years, with a mean age of 13 years. Fifty-two percent of participants were boys, 68 percent were Caucasian, and 32 percent were Hispanic.
Objective measures were gathered using full polysomnography during one night of sleep at home. Children and their parents completed sleep questionnaires the following morning. Eighty-seven percent of parent questionnaires were filled out by mothers.
The authors noted that in cases with high disagreement between parent report and child report, the child report tended to be more accurate for sleep duration. In contrast, the parent report was more accurate for sleep latency.
The authors also performed a stratified analysis of children from 9 to 12 years of age, compared to children 13 to 17 years of age.
"We expected that for teenagers, parent report of sleep would be less accurate compared to parent report for younger children," said Dr. Combs. "Surprisingly, there was no difference in parent versus child report about sleep in teenagers."
https://www.sciencedaily.com/releases/2019/02/190214093413.htm
Teens too low on sleep, activity, and too high on screen time
February 4, 2019
Science Daily/University of Texas Health Science Center at Houston
Only 1 in 20 U.S. adolescents is meeting national recommendations for sleeping, physical activity, and screen time, according to new research.
The study, published today in JAMA Pediatrics, also revealed differences in the findings between females and males, with just 3 percent of girls reaching all three guideline targets, compared to 7 percent of boys.
"There is plenty of evidence to show how teenagers aren't getting enough physical activity, or sufficient sleep, or keeping their screen time in check. But this is the first time these three factors, which have a crucial bearing on a child's health, have been analyzed together among a nationally representative sample of U.S. adolescents," said first author Gregory Knell, PhD, a postdoctoral research fellow at UTHealth School of Public Health in Dallas. "The results are a wake-up call for everyone who wants to make sure our children have a healthy future."
It is recommended by the National Sleep Foundation that children ages 14-18 sleep eight to 10 hours a night. The U.S. Department of Health and Human Services recommends at least an hour of moderate or vigorous physical activity daily, and limiting screen time to less than two hours.
The research involved nearly 60,000 American high school students, using data from the 2011-2017 Youth Risk Behavior Surveillance Survey.
"By far the most startling finding was how few adolescents across the board are meeting all three recommendations," Knell said. "I expected the percentage of adolescents meeting all three requirements concurrently to be low, but not this low.
The combined effect on children's overall health could be considerable in terms of their physical health, emotional well-being, and academic performance."
The study further examined other attributes of the child -- age, race or ethnicity, weight, and mental health -- and how these were linked to sleep, physical activity, and screen time.
Findings showed older teenagers, non-Hispanic black children, Asian children, those classified as obese, and those who showed signs of depression were the least likely to meet all recommendations when compared to their counterparts.
The paper calls for more research to better understand the relationship among sleep, physical activity, and screen time by exploring the effect these behaviors have on each other and their wider implications over time. It also urged doctors to ask patients about these behaviors, provide them and their parents with advice, and make any necessary specialist referrals.
"These findings are only scratching the surface and demonstrate a need to learn more about the role parenting style and home environment may play in increasing or curtailing these behaviors," Knell said. "Although the study confirms and further reveals how few children are leading optimal lifestyles, it also raises many questions about what can be done to reverse that trend and improve their health."
https://www.sciencedaily.com/releases/2019/02/190204114643.htm
Time parents spend with children key to academic success
Study used parental death, divorce to measure impact
February 4, 2019
Science Daily/Ohio State University
The time parents spend with their children has a powerful effect on their educational achievement, according to a large study with a novel approach. Researchers analyzed data on children in Israel who lost a parent through death or divorce.
Researchers analyzed data on children in Israel who lost a parent through death or divorce.
They found that when it came to one measure of a child's academic success, the educational attainment of the surviving or custodial parent had more impact than the educational level of the parent who died or left the home.
And the longer the absence of a parent, the less impact his or her education had on the child's success and the greater the impact of the remaining parent.
"In the ongoing debate over what helps children succeed academically, we show that genetics is not the only major factor," said Bruce Weinberg, co-author of the study and professor of economics at The Ohio State University.
"It is also about the time that parents spend with their children."
The research was conducted by Eric Gould and Avi Simhon of Hebrew University in Israel, as well as Weinberg. The study has been accepted for publication in the Journal of Labor Economics and will be published Feb. 4, 2018 on the website of the National Bureau of Economic Research.
The study involved more than 22,000 children in Israel who lost a parent before age 18, more than 77,000 whose parents divorced and more than 600,000 who did not experience parental death or divorce.
The researchers looked at whether these children passed the "matriculation exam," a high-stakes test required to attend college. About 57 percent of high-school students in the country pass the test.
The researchers started the study by looking at children who experienced the death of one parent, Weinberg said.
"We found that if a mother dies, her education becomes less important for whether her child passes the test, while at the same time the father's education becomes more important. If a father dies, the reverse happens," he said.
"These relationships are stronger when the parent dies when the child is younger."
In other words, Gould said, parenting matters.
"Student success is not coming just from smart parents having smart kids," he said.
Study results rejected the argument that the parents' income is really what helps the children of the highly educated succeed academically.
If that were so, then losing a father should hurt children academically more than losing a mother because fathers tend to earn more.
"That's not what we found. The loss of a mother -- who tends to spend more time than the father with her children -- had a bigger effect than loss of a father in our study," Weinberg said.
But what about parents who remarry after losing a spouse? The study found that the negative effect on academic success of losing a mother can at least be partially minimized if the child gains a stepmother. If the father does not remarry, the effect of the loss is more acute: No one can compensate for the loss of the mother except for the father.
The study didn't find any differences in academic success for children whose mothers remarried after their father died, versus those who did not. That may be because mothers' education levels generally had more impact on their children's success than that of fathers because of the more time moms spend with their kids.
Results also showed that mothers' education was more closely linked to children's academic success in larger families. The researchers believe that was because women with more children spent more time with their kids and less time working outside the home, according to findings.
Overall, the effects of losing a parent were stronger on girls than on boys, the study showed.
Similar results were also found with children whose parents had divorced. The educational level of the mother -- whom the child typically lived with -- had a larger effect on academic success than did the education of the other parent, Weinberg said.
"We found similar results in those children who experienced parental death and parental divorce. That provides strong evidence that our results are more general than just for children who suffered a parental death," Weinberg said.
"Other studies show that highly educated parents tend to spend more time with their children. Our results may suggest one reason why they do: It has a strong impact on academic success."
https://www.sciencedaily.com/releases/2019/02/190204085926.htm
Children looking at screens in darkness before bedtime are at risk of poor sleep
January 29, 2019
Science Daily/University of Lincoln
Preteens who use a mobile phone or watch TV in the dark an hour before bed are at risk of not getting enough sleep compared to those who use these devices in a lit room or do not use them at all before bedtime.
The study by researchers from the University of Lincoln, Imperial College London, Birkbeck, University of London and the Swiss Tropical and Public Health Institute in Basel, Switzerland is the first to analyse the pre-sleep use of media devices with screens alongside the impact of room lighting conditions on sleep in pre-teens.
It found that night-time use of phones, tablets and laptops is consistently associated with poor sleep quality, insufficient sleep, and poor perceived quality of life. Insufficient sleep has also been shown to be associated with impaired immune responses, depression, anxiety and obesity in children and adolescents.
Data was collected from 6,616 adolescents aged between 11 and 12 and more than 70 per cent reported using at least one screen based device within one hour of their bedtime. They were asked to self-report a range of factors including their device use in both lit and darkened rooms, their weekday and weekend bedtimes, how difficult they found it to go to sleep and their wake up times.
The results showed that those who used a phone or watched television in a room with a light on were 31 per cent more likely to get less sleep than those who didn't use a screen. The likelihood increased to 147 per cent if the same activity took place in the dark.
It has been reported that globally, 90 per cent of adolescents are not sleeping the recommended nine to 11 hours per night, which has coincided with an increase in the use of screen-based media devices. In the UK alone, it is estimated that 98 per cent of 12 to 15 year olds watch television and over 90 per cent use mobile phones at home.
Previous studies have shown that sufficient sleep duration and quality are vital in childhood to maintain physical and mental development. Sleep is also crucial for cognitive processes and a lack of sufficient sleep has been directly related to poor academic performance.
Lead author, Dr Michael Mireku, a researcher at the University of Lincoln's School of Psychology said: "While previous research has shown a link between screen use and the quality and length of young people's sleep, ours is the first study to show how room lighting can further influence this.
"Our findings are significant not only for parents but for teachers, health professionals and adolescents themselves. We would recommend that these groups are made aware of the potential issues surrounding screen use during bedtime including insufficient sleep and poor sleep quality."
https://www.sciencedaily.com/releases/2019/01/190129101904.htm
How teens deal with stress may affect their blood pressure, immune system
December 13, 2018
Science Daily/Penn State
Most teens get stressed out by their families from time to time, but whether they bottle those emotions up or put a positive spin on things may affect certain processes in the body, including blood pressure and how immune cells respond to bacterial invaders, according to researchers.
The researchers explored whether the strategies adolescents used to deal with chronic family stress affected various metabolic and immune processes in the body. Strategies could include cognitive reappraisal -- trying to think of the stressor in a more positive way -- and suppression, or inhibiting the expression of emotions in reaction to a stressor.
The team found that when faced with greater chronic family stress, teens who used cognitive reappraisal had better metabolic measures, like blood pressure and waist-to-hip ratio. Teens who were more likely to use suppression tended to have more inflammation when their immune cells were exposed to a bacterial stimulus in the lab, even in the presence of anti-inflammatory signals.
Hannah Schreier, assistant professor of biobehavioral health at Penn State, said the results suggest that the coping skills teens develop by the time they are adolescents have the potential to impact their health later in life.
"These changes are not something that will detrimentally impact anyone's health within a week or two, but that over years or decades could make a difference," Schreier said. "That may be how small changes in metabolic or inflammatory outcomes may become associated with poorer health or a greater chance of developing a chronic disease later in life."
Emily Jones, graduate student in biobehavioral health at Penn State, said the results -- recently published in Psychosomatic Medicine -- help therapists and counselors better work with children and adolescents who live in stressful environments.
"Exposure to chronic stress doesn't always lead to poorer health outcomes, in part because of differences among people," Jones said. "As our study findings suggest, there may be ways to help someone be more resilient in the face of stress by encouraging certain emotion regulation strategies. For children in stressful living situations, we can't always stop the stressors from happening, but we may be able to help youth deal with that stress."
Although previous research has linked chronic stress during childhood with such conditions as depression, autoimmune disorders and cardiovascular disease, the researchers said less is known about why some people under chronic stress develop these conditions while others do not. While it was thought that emotional regulation may play a role, the researchers were not sure exactly how.
To better explore how different ways of regulating emotions can affect different aspects of physical health, the researchers gathered data from 261 adolescents between the ages of 13 and 16 years.
The researchers interviewed the participants about the relationships and chronic stress within their families, as well as measured the participants' waist-to-hip ratios and blood pressure. The adolescents also completed questionnaires about how they regulated their emotions.
To measure immune function, the researchers took blood samples from each participant and exposed the blood to a bacterial stimulus -- both with and without the anti-inflammatory substance hydrocortisone -- to see how the immune cells would respond.
The researchers found that under conditions of greater chronic family stress, the immune cells of adolescents who were more likely to use suppression also tended to produce more pro-inflammatory cytokines, molecules that signal to other cells that there is a threat present and that the body's immune system needs to kick into gear.
The cells of these teens produced more cytokines even in the presence of hydrocortisone, an anti-inflammatory substance that usually tells the body to slow down on producing cytokines.
"Cytokines are like messengers that communicate to the rest of the body that added support is needed," Jones said. "So when you have a high level of these pro-inflammatory cytokines, even in the presence of anti-inflammatory messages from cortisol, it may suggest that your body is mounting an excessive inflammatory response, more so than necessary. It suggests that the immune system may not be functioning as it should be."
Meanwhile, the researchers found that adolescents who tended to use cognitive reappraisal while under more family stress had smaller waist-to-hip ratios -- a measurement used as an indicator of health and chronic disease risk -- and lower blood pressure.
"While we would have to follow up with more studies, the results could lend support to the idea that reappraising a situation during times of stress could be beneficial," Jones said. "For a mild stressor, this could be as simple as reframing a bad situation by thinking about it as a challenge or an opportunity for growth."
The researchers added that opportunities for future studies could include looking at the effects of emotion regulation strategies on these metabolic and immune measures over time to tease apart how the family environment shapes emotion regulation, how emotion regulation may itself influence stress exposure, and how chronic family stress and emotion regulation together can affect chronic disease risk in the long run.
https://www.sciencedaily.com/releases/2018/12/181213131236.htm
Teens get more sleep with later school start time
December 12, 2018
Science Daily/University of Washington
In 2016, Seattle Public Schools pushed back start times for its 18 high schools by 55 minutes. Researchers have now announced that, as a result, teens at two Seattle high schools got more sleep on school nights -- a median increase of 34 minutes of sleep each night -- and showed improved attendance and grades.
When Seattle Public Schools announced that it would reorganize school start times across the district for the fall of 2016, the massive undertaking took more than a year to deploy. Elementary schools started earlier, while most middle and all of the district's 18 high schools shifted their opening bell almost an hour later -- from 7:50 a.m. to 8:45 a.m. Parents had mixed reactions. Extracurricular activity schedules changed. School buses were redeployed.
And as hoped, teenagers used the extra time to sleep in.
In a paper published Dec. 12 in the journal Science Advances, researchers at the University of Washington and the Salk Institute for Biological Studies announced that teens at two Seattle high schools got more sleep on school nights after start times were pushed later -- a median increase of 34 minutes of sleep each night. This boosted the total amount of sleep on school nights for students from a median of six hours and 50 minutes, under the earlier start time, to seven hours and 24 minutes under the later start time.
"This study shows a significant improvement in the sleep duration of students -- all by delaying school start times so that they're more in line with the natural wake-up times of adolescents," said senior and corresponding author Horacio de la Iglesia, a UW professor of biology.
The study collected light and activity data from subjects using wrist activity monitors -- rather than relying solely on self-reported sleep patterns from subjects, as is often done in sleep studies -- to show that a later school start time benefits adolescents by letting them sleep longer each night. The study also revealed that, after the change in school start time, students did not stay up significantly later: They simply slept in longer, a behavior that scientists say is consistent with the natural biological rhythms of adolescents.
"Research to date has shown that the circadian rhythms of adolescents are simply fundamentally different from those of adults and children," said lead author Gideon Dunster, a UW doctoral student in biology.
In humans, the churnings of our circadian rhythms help our minds and bodies maintain an internal "clock" that tells us when it is time to eat, sleep, rest and work on a world that spins once on its axis approximately every 24 hours. Our genes and external cues from the environment, such as sunlight, combine to create and maintain this steady hum of activity. But the onset of puberty lengthens the circadian cycle in adolescents and also decreases the rhythm's sensitivity to light in the morning. These changes cause teens to fall asleep later each night and wake up later each morning relative to most children and adults.
"To ask a teen to be up and alert at 7:30 a.m. is like asking an adult to be active and alert at 5:30 a.m.," said de la Iglesia.
Scientists generally recommend that teenagers get eight to 10 hours of sleep each night. But early-morning social obligations -- such as school start times -- force adolescents to either shift their entire sleep schedule earlier on school nights or truncate it. Certain light-emitting devices -- such as smartphones, computers and even lamps with blue-light LED bulbs -- can interfere with circadian rhythms in teens and adults alike, delaying the onset of sleep, de la Iglesia said. According to a survey of youth released in 2017 by the U.S. Centers for Disease Control and Prevention, only one-quarter of high school age adolescents reported sleeping the minimum recommended eight hours each night.
"All of the studies of adolescent sleep patterns in the United States are showing that the time at which teens generally fall asleep is biologically determined -- but the time at which they wake up is socially determined," said Dunster. "This has severe consequences for health and well-being, because disrupted circadian rhythms can adversely affect digestion, heart rate, body temperature, immune system function, attention span and mental health."
The UW study compared the sleep behaviors of two separate groups of sophomores, all enrolled in biology classes at Roosevelt and Franklin high schools. One group of 92 students, drawn from both schools, wore wrist activity monitors all day for two-week periods in the spring of 2016, when school still started at 7:50 a.m. The wrist monitors collected information about light and activity levels every 15 seconds, but no physiological data about the students. In 2017, about seven months after school start times had shifted later, the researchers had a second group of 88 students -- again drawn from both schools -- wear the wrist activity monitors. Researchers used both the light and motion data in the wrist monitors to determine when the students were awake and asleep. Two teachers at Roosevelt and one at Franklin worked with the UW researchers to carry out the study, which was incorporated into the curriculum of the biology classes. Students in both groups also self-reported their sleep data.
The information obtained from the wrist monitors revealed the significant increase in sleep duration, due largely to the effect of sleeping in more on weekdays.
"Thirty-four minutes of extra sleep each night is a huge impact to see from a single intervention," said de la Iglesia.
The study also revealed other changes beyond additional shut-eye. After the change, the wake-up times for students on weekdays and weekends moved closer together. And their academic performance, at least in the biology course, improved: Final grades were 4.5 percent higher for students who took the class after school start times were pushed back compared with students who took the class when school started earlier. In addition, the number of tardies and first-period absences at Franklin dropped to levels similar to those of Roosevelt students, which showed no difference between pre- and post-change.
The researchers hope that their study will help inform ongoing discussions in education circles about school start times. The American Academy of Pediatrics recommended in 2014 that middle and high schools begin instruction no earlier than 8:30 a.m., though most U.S. high schools start the day before then. In 2018, California lawmakers nearly enacted a measure that would ban most high schools from starting class before 8:30 a.m. In 2019, Virginia Beach, home to one of the largest school districts in Virginia, will consider changes to its school start times.
https://www.sciencedaily.com/releases/2018/12/181212140741.htm
Regular bedtimes and sufficient sleep for children may lead to healthier teens
December 6, 2018
Science Daily/Penn State
Having a regular, age-appropriate bedtime and getting sufficient sleep from early childhood may be important for healthy body weight in adolescence, according to researchers.
The researchers identified groups of children by bedtime and sleep routines and tested longitudinal associations for each group with adolescent body mass index (BMI). Results are published Dec. 4 in the journal SLEEP.
The findings suggest that childhood bedtime and sleep routine groups predict adolescent sleep patterns and BMI.
In a national study of urban households, one-third of children consistently adhered to age-appropriate bedtimes for ages 5 through 9. Those who had no bedtime routine at age 9 had shorter self-reported sleep duration and higher BMI at age 15, when compared to those children with age-appropriate bedtimes (after adjusting for age 3 BMI).
"Parenting practices in childhood affect physical health and BMI in the teenage years. Developing a proper routine in childhood is crucial for the future health of the child," said co-author Orfeu Buxton, professor of biobehavioral health at Penn State, and director of the Sleep, Health, and Society Collaboratory at Penn State. "We think sleep affects physical and mental health, and the ability to learn."
Bedtimes should be determined by various factors, such as when the child has to wake up based on the time it takes for that child to get ready for school, and the time it takes to get to school, as well as the school start time. School start times aren't determined by parents, but bedtimes and bedtime routines can be adjusted by parents, suggests Buxton.
"Giving children the time frame to get the appropriate amount of sleep is paramount," Buxton said, as achieving recommended duration of sleep can have an impact on BMI in adolescent years, according to the findings.
Bedtime should provide enough of a "window" for the child to get an appropriate amount of sleep, even if the child doesn't fall asleep right away, said Buxton.
This study supports existing pediatric recommendations that having a regular and age-appropriate bedtimes is important for children's health, said lead author Soomi Lee, now assistant professor of aging studies in the College of Behavioral and Community Sciences at the University of South Florida. Lee, who was at Penn State at the time of the study, received her graduate degree in human development and family studies, and her post-doctoral degree in biobehavioral health, at Penn State.
Additionally, the study shows continuity in sleep behaviors, Lee said, in that those who had most optimal bedtime and sleep routines during childhood also had sufficient sleep duration in adolescence, whereas those with suboptimal bedtime and sleep routines had insufficient sleep duration in adolescence, she said.
Researchers analyzed longitudinal data from the Fragile Families and Child Wellbeing Study, a national cohort from 20 United States cities, with 2,196 subjects.
Childhood bedtime and sleep routines were assessed by mothers' reports of their children's presence and timing of bedtimes, adherence to bedtimes, and habitual sleep duration at ages 5 and 9. At age 15, these adolescents reported their height and weight, which were used to calculate BMI.
Lee said the study highlights the importance of educating parents in bedtime parenting, especially for those in low-income households.
"In our sample that includes a large proportion of low-income, low-education, and ethnic minority households, only less than one third of children had age-appropriate bedtime routines at age 5 and 9," Lee said. "This raises a concern about development and health of children in disadvantaged households. Future family interventions may need to include parental educations about sleep health, particularly focusing on parents with low income and low education."
Additionally, future studies should focus on whether childhood sleep behavior interventions promote healthier sleep and weight in later life course stages, said Lee.
This research was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health.
https://www.sciencedaily.com/releases/2018/12/181206114752.htm