PROVIDENCE, RI – A pilot study conducted in a small private high school confirms what many have been touting for years: the benefits of a delayed school start time. Judy Owens, MD, a sleep expert with Hasbro Children’s Hospital, reports that a modest delay in school start time of only 30 minutes was associated with significant improvements in adolescent alertness, mood and health. Her findings are published in the July issue of the Archives of Pediatric and Adolescent Medicine.

Inadequate sleep in adolescents, defined as less than nine hours per night, is a known problem and a major public health concern. Owens and other pediatric sleep experts have been encouraging delayed school start times to address the concern. To prove the benefits of a delayed start time in doing so, Owens conducted a study at a small private high school in Rhode Island, which delayed their start time from 8 a.m. to 8:30 a.m.

Biological changes in adolescents can cause what is known as a “phase delay,” which calls for later sleep onset and wake times due to a shift in circadian rhythms. The optimal sleep amount for adolescents is nine to 9 1/4 hours per night, despite the shift in their preferred wake/sleep times. Owens, who is also an associate professor at The Warren Alpert Medical School Brown University says, “On a practical level, this means that the average adolescent has difficulty falling asleep before 11 p.m., so the ideal wake time is around 8 a.m.”

She also notes, “In addition to these biological factors, adolescents are exposed to multiple environmental and lifestyle factors such as extracurricular activities, homework and after-school jobs, which can all significantly impact their sleep patterns. As a result of sleep loss during the week, adolescents often “sleep in” on the weekends, further contributing to a disruption of their circadian rhythm and decreased daytime alertness levels.” Owens comments further, “It’s not surprising that a large number of studies have now documented that the average adolescent is chronically sleep-deprived and pathologically sleepy.”

The consequences of sleep deprivation are far-reaching: impairments in mood, attention and memory, behavior control and quality of life; lower academic performance and a decreased motivation to learn; and health-related effects including increased risk of weight-gain, lack of exercise and use of stimulants.

During the winter term, the start time at St. George’s School was delayed by 30 minutes, to 8:30 a.m. In order to avoid extending the length of the school day, small schedule changes (five to 10 minutes) were made across both academic and non-academic periods. For boarding students, lights out procedures and restrictions on use of electronics did not change.

Students who received parental permission and who agreed to participate in the study responded to an e-mail survey that was conducted both before and after the start time change. The Sleep Habits Survey (SHS) is a comprehensive 8-page self-report survey that has been administered to over 3,000 high school students in RI, as well as in a number of other countries, and is used to evaluate typical sleep and wake behaviors. It also includes scales measuring sleepiness, sleep-wake behavior problems and depression. Of the 278 students who agreed to the survey and received consent, 225 completed the first survey and 201 completed the second survey.

The study found that there was a significant average increase in sleep duration on school nights of 45 minutes across all grades (nine to 12) after the change in the school start time. The self report showed drastic declines in the percent of students who felt they “rarely/never” got enough sleep (69 percent to 34 percent), and those reporting “never” being satisfied with their sleep (37 to 9 percent).

Other findings of note are that fewer students reported being impacted by fatigue or lack of motivation, and the percent of students rating themselves as “at least somewhat unhappy” or depressed decreased significantly, from 66 percent to 45 percent. Also, there was a considerable reduction in the number of students who reported visiting the school’s health center for “fatigue-related complaints,” dropping from 15 percent to only five percent. Meanwhile, the health center also reported a 56 percent decrease in requests for “rest passes.” Another finding supporting the benefits of the delayed start time is that teachers reported a 36 percent reduction in absences or tardiness for the first class of the day.

Overall the percent of students getting less than seven hours of sleep after the change in school start time decreased by 80 percent. Still, only a small minority of the students (11 percent) reported getting the recommended nine or more hours of sleep. Owens sums up the findings, “A modest start time delay was associated with a significant increase in self-reported sleep duration and a decrease in a number of ratings of daytime sleepiness. Perhaps most importantly, students rated themselves as less depressed and more motivated to participate in a variety of activities.”

The researchers conclude, “The ongoing debate regarding the more widespread institution of later school start times is a controversial one with many logistical considerations. It is particularly important to continue to assess outcomes in schools that have implemented such a change.” They also comment, “The results of this study add to the growing literature that supports the potential benefits of such an adjustment to better support adolescents’ sleep needs and circadian rhythm in order to improve the learning environment and their overall quality of life.”

Source: Jessica Grimes, Lifespan via EurekAlert

Earlier bedtimes were linked to higher scores in most of the developmental measures.

Children who slept less than 11 hours per night, the AASM’s recommended minimum for preschoolers, scored lower on phonological awareness, literacy and early math skills. Insufficient sleep may hurt a child’s development and school achievement.

The findings were based on a sample of 8,000 children assessed in the Early Childhood Longitudinal Study – Birth Cohort. The longitudinal study sponsored by the U.S. Department of Education and the National Center for Education Statistics followed children’s health, development, care and education from birth to the start of kindergarten.

In the government study parents reported usual bedtime and wake time. The children took a shortened set of items from standardized assessments to determine developmental outcomes.

The principal author of the study recommends parents help their preschooler get healthy sleep and encourage development by setting a regularly bedtime and establishing routines such as bedtime readings or stories.

Source: American Academy of Sleep Medicine

Results indicate that the rate of persistence after 5 years was 29% for children with bedwetting and 27% for children with sleepwalking. The overall prevalence for these parasomnias was 2.6% and 3.1%, respectively. The study also found that the incidence rate for new cases of sleepwalking was 3.2% during the follow-up period, while the incidence rate for new cases of bedwetting was less than 1%.

“Current wisdom was that most of these behaviors remitted by adolescence,” said principal investigator Stuart F. Quan, MD, professor emeritus of medicine at the University of Arizona in Tucson. “Our data indicate that in a number of children, they will persist. Because parasomnias such as sleepwalking can be injurious as children grow older, parents need to be cognizant and be prepared to protect them from injury.”

The study involved 310 children in the Tucson Children’s Assessment of Sleep Apnea Study (TuCASA), a prospective cohort study that enrolled children between the ages of 6 and 11 years for an initial assessment. The children were studied again after a mean interval of 4.6 years. At both time points, parents were asked to complete comprehensive sleep habit surveys.

Results also show that all cases of sleep terrors remitted by adolescence. The most common problem was sleep talking, which had a prevalence rate of 22.3% and persisted into adolescence in 46% of cases. However, Quan noted that sleep talking typically is a minor hindrance that requires no treatment.

Source: Sleep Review

In a study of young children, researchers showed that insomnia symptoms were consistently associated with impaired heart variability measures. They also found a significant but less consistent pattern with shortened sleep duration and decreased heart rate variability.

Heart rate variability is the beat-to-beat variations of heart rate. In a healthy person, beat-to-beat intervals change slightly in response to automatic functions like breathing.

The study included 612 elementary school children in the first to fifth grades. The children were average age 9, and 25 percent were non-white and 49 percent were boys. All were generally in good health. Their parents completed the Pediatric Behavior Scale, including two questions that focused on symptoms of insomnia.

Researchers examined the children overnight in a sleep laboratory with polysomnography (PSG), a standardized method for measuring sleep disorders. The researchers measured sleep duration, trouble falling asleep, the number of wake-ups and problems going back to sleep if awakened. They also measured cardiac autonomic modulation (CAM), the balance of the sympathetic and the parasympathetic control of the heart rate rhythm.

A balance is needed between the sympathetic modulation that “excites” the heart and the parasympathetic modulation that “calms” the heart, said Mr. Fan He, the lead-author of the study and a graduate student at Penn State University College of Medicine in Hershey, Pa. “The balance between the sympathetic and the parasympathetic provides a favorable profile for the heart.”

The study showed:

• Children with reported insomnia had impaired CAM with a shift towards more sympathetic or excitable activation of the heart rhythm. There was a 3 percent to 5 percent reduction in the parasympathetic modulation of heart rhythm in children with insomnia.
• Children with longer sleep duration had a slower heart rate indicative of a balance of heart rhythm, with a shift towards more parasympathetic modulation. The heart rate of children who slept eight hours was two beats per minute slower than that of kids who slept only seven hours.
• Insomnia and short sleep duration, even in young children, resulted in a physiological activation of the sympathetic modulation.

“Kids who sleep a longer duration have a healthier heart regulation profile compared to kids who sleep shorter durations,” said Duanping Liao, M.D., Ph.D., co-author of the study and professor of epidemiology at Penn State University College of Medicine in Hershey, Pa. “Their hearts are more excitable if they have insomnia. If the heart is too excited, that means it is beating too fast and usually that isn’t good. These data indicate that among young children with insomnia symptoms reported by their parents, there already is an impairment of cardiovascular autonomic regulation, long before they reach the traditional high-risk period for cardiovascular disease.”

Parents should encourage their children to have healthy bedtime habits that encourage sleep, Liao said. “Watching television before going to bed and waking up to return text messages are examples of activities that could have a harmful affect on healthy sleep patterns in children.”

Liao called for further studies in children to determine the impact of sleep deprivation and stress and the possible long-term risk of cardiovascular disease and obesity. “Previous studies have shown a strong association of heart rhythm regulation and heart risk in adults. It’s quite possible that this kind of stress can have a long-term impact even at a young age.”

The study was funded by the National Heart, Lung, and Blood Institute.

Other co-authors are: Xian Li, M.D., M.S.; Sol Rodriguez-Colon, M.S.; Alexandros N. Vgontzas, M.D.; Chuntao Wu, M.D., Ph.D.; and Edward O. Bixler, Ph.D. Author disclosures are on the abstract.

Source: Karen Astle, American Heart Association

“We found that in the tonsil tissues of children with OSA, certain genes and gene networks were over expressed,” said David Gozal, M.D., professor and chair of the Department of Pediatrics, who led the study. “We believe that the results of this gene overexpression is increased proliferation of the adenotonsillar tissues, which in turn can cause partial or complete obstruction of the upper airways during sleep.”

The findings have been published online ahead of print publication in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.

In the United States, two to three percent of children have OSA. The current standard of treatment is surgical removal on the tonsils, but surgery is not without risks and potential complications. Currently, about 600,000 tonsillectomies are performed each year in children, primarily to treat OSA.

Dr. Gozal and colleagues have been studying potential non-surgical alternatives to treat OSA in children. To identify potential pharmacological targets, they recruited 18 children with OSA and 18 age-, gender-, and ethnicity-matched children with recurrent tonsillar infections (RI), all of who underwent surgery to have their tonsils removed.

The tonsil tissue from each subject was analyzed for relative expression of the 44,000 known genes in the human genome. The researchers then further analyzed the gene pathways to determine which changes may represent differences with a high likelihood of impact on cellular proliferation.

“We wanted to find the most important and functionally pertinent genes, those with the most connectivity,” explained Dr. Gozal. “We identified 47 genes and among those, two specific genes, both phosphatases, which are known to be very important at regulating communication in cells. Then we looked at the expression of the phosphatase protein and found that children with OSA have higher level of phosphatases in the tonsils.” In particular, they focused on one protein called phosphoserine phosphatase (PSPH) that was expressed in children with OSA, but almost never expressed in the children with RI.

“We asked, ‘What happens if we block this phosphatase?’” said Dr. Gozal. “Is this a potential target for pharmacological therapy?” Indeed, they found that introducing calyculin, a phosphatase inhibitor, reduced the cell proliferation and increased programmed cell death, or apoptosis, a process by which cells self-regulate, in the tonsils of OSA patients. “Together, these observations suggest that PSPH is a logical therapeutic target in reversing adenotonsillar enlargement in pediatric OSA,” Dr. Gozal wrote.

“The next direction is to identify if selective clones of proliferating cells that may be affected by PSPH or by another of the discovered target genes with the intent of developing a non-surgical alternative treatment to surgery for OSA in children,” said Dr. Gozal. “If there is a subgroup of cells that have specific markers, then we may be able to develop a therapy that could be specifically targeted to these cells.”

“Phosphatases such as PSPH are an exciting prospective target for therapy in children with OSA,” said Dr. Gozal. “We believe if we had effective non-surgical alternatives to tonsillectomies, it would be of great benefit.”

Source: Keely Savoie, American Thoracic Society

The five-year grant will allow pediatric researchers, led by Daphne Koinis-Mitchell, PhD, to evaluate the connection between asthma and allergic rhinitis symptoms (such as sneezing, congestion or a runny nose), sleep quality, and school functioning in urban, elementary school children between the ages of 7 and 9. Working in collaboration with school districts in the greater Providence area, the investigators will also look at how family and cultural risks, such as family management of asthma and allergic rhinitis and asthma-related fear, may contribute to these associations.

“We know that asthma can affect how children perform in school. However, studies have not specifically shown how asthma and allergic rhinitis symptoms influence school functioning,” said Koinis-Mitchell, a child psychologist with the Bradley Hasbro Children’s Research Center. “We propose that asthma-related sleep interruptions and/or frequent school absences due to asthma symptoms may make a difference in how well these children do in school.”

As part of this longitudinal study, researchers will monitor children’s sleep quality, nasal peak flow (to capture changes in rhinitis symptoms) and lung function (to document changes in asthma symptoms) for one month, three times a year. They also will collect academic performance indicators from the children’s schools, based on reports from teachers and school nurses, over the course of the year.

“We’re excited to work with schools here in Providence to try and better explain the relationship between persistent asthma and academic achievement,” said Koinis-Mitchell, who is also an assistant professor of psychiatry (research) at The Warren Alpert Medical School of Brown University.

According to the Centers for Disease Control and Prevention, asthma has now become the most common pediatric chronic illness in the United States, affecting an estimated 4.8 million children. It is also the leading cause of school absences due to chronic illness among children ages 5 to 17, the Asthma and Allergy Foundation of America reports.

Study co-investigators include Robert Klein, MD, of Hasbro Children’s Hospital and Alpert Medical School; Gregory K. Fritz, MD; Elizabeth McQuaid, PhD; Ronald Seifer, PhD; Jack Nassau, PhD; and Julie Boergers, PhD, all of the Bradley Hasbro Children’s Research Center and Alpert Medical School; and Monique Lebourgeois, PhD, of Brown University.

Source: Jessica Collins Grimes, Lifespan

The study, which appears online in the Journal of Adolescent Health, evaluated responses from 12,000 students in grades 9 through 12 who participated in the 2007 national Youth Risk Behavior Survey.

The authors found that 10 percent of adolescents sleep only five hours and 23 percent sleep only six hours on an average school night. More females than males have sleep deficits as do more African-Americans and whites compared to Hispanics. Nearly 20 percent more 12th-grade students have sleep deficits than do those in ninth grade.

The findings of this study were consistent with those reported from the National Sleep Foundation’s 2006 Sleep in America Poll, the authors say, adding that that although no formally accepted sleep guidelines exist, the foundation defines nine hours a night as optimal for adolescents, eight hours as borderline and anything under eight hours as not enough.

“The natural sleep-wake pattern shifts during adolescence, making earlier bed time and wake times more difficult. The result for students with early school start-times is a chronic sleep deficit,” said lead study author Danice Eaton, Ph.D., of the Centers for Disease Control and Prevention.

As students progress through high school, demands on their time from hectic social activities, jobs, homework and family obligations increase and they sleep less to fit them in, as the study shows. Compounded with their delayed sleep-wake pattern, many students are getting up for school when their bodies tell them it is still the middle of the night.

National Sleep Foundation research shows that delaying school start-times by an hour or more increases the amount of sleep adolescents get and improves their performance in school. However, to promote optimal sleep, Eaton said that adolescents should have set bedtimes before 10 p.m. on school nights and consistent wake-sleep times every night.

Brandy Roane, an expert in adolescent sleep patterns at the Munroe-Meyer Institute of Genetics and Rehabilitation of the University of Nebraska Medical Center, said, “Given adolescents’ downward spiraling tendency of depriving themselves of sleep during the week and playing catch-up on the weekend, more research exploring ways to intervene would be beneficial.”

Eaton DK, et al. Prevalence of insufficient, borderline, and optimal hours of sleep among high school students United States, 2007. J Adolesc Health online, 2010.

Source: Health Behavior News Service

Researchers found that exposure to secondhand smoke can be associated with sleep problems among children with asthma, including difficulties falling asleep, more sleep-disordered breathing and increased daytime sleepiness. Sleep efficiency has been shown to improve with effective asthma treatment, but study authors feel that the reduction or elimination of secondhand smoke can have significant impact on physical and emotional health and school performance among the pediatric population.

Source: American Academy of Pediatrics

Results show that over the two-year course of the study, sleep onset was significantly delayed by an average of 50 minutes, and sleep time was significantly reduced by an average of 37 minutes. Girls had higher sleep efficiency and reported fewer night wakings than boys. Initial levels of sleep predicted an increase in pubertal development over time, whereas there was no similar prediction in the opposite direction. According to the authors, this suggests that the neurobehavioral changes associated with puberty may be seen earlier in measures of sleep organization than in bodily changes.

Lead author Avi Sadeh, D.Sc, professor of psychology at Tel Aviv University in Israel, said that biological factors have a significant influence on sleep during puberty; however, psychosocial issues such as school demands, social activities and technological distractions can lead to the development of bad sleep habits. Therefore, parents and educators can play an important role in helping children understand how to prioritize sleep as they grow and mature.

“It is very important for parents to be aware of the importance of sleep to their developing teenager and to maintain their supervision throughout the adolescent years,” said Sadeh. “School health education should also provide children with compelling information on how insufficient sleep compromises their well-being, psychological functioning and school achievements.”

According to the authors, sleep-wake organization undergoes significant reorganization during the transition to adolescence. The main changes include a delayed sleep phase, which involves a tendency for later bedtimes and rise times; shorter sleep, which is associated with increased levels of daytime sleepiness; and irregular sleep patterns, which involve sleeping very little on weekdays and sleeping longer during weekends to partially compensate for this sleep loss. During maturation adolescents also develop greater tolerance to sleep deprivation or extended wakefulness.

Data from 94 children (41 boys and 53 girls) were collected from a larger study on sleep and neurobehavioral functioning during the transition to puberty. Children were recruited from regular classes of five different elementary schools in the Tel Aviv area. At first assessment the age range was about 10 years to 11 years. Each child completed a number of questionnaires, including the Sexual Maturation Scale (SMS) and the Puberty Development Scale (PDS) for pubertal development assessment. All children were healthy with no chronic medical or psychological problems.

Sleep-wake patterns were observed subjectively with a sleep diary and objectively using an actigraph, which the children wore on their wrist. The same assessment was repeated, at a similar time of year, for two successive years. Eighty-two children completed the second assessment, and 72 completed the third assessment.

The authors noted that Israel has a six-day school week, with Friday being the only day that is not followed by school. As expected, significant differences were found between sleep on Friday nights and sleep on school nights. On Fridays, sleep onset was delayed, sleep time was extended and sleep quality was poorer in comparison with school nights. These differences were not associated with puberty status or gender, suggesting that the tendency for weekend compensatory sleep is relatively steady over the period of early adolescence.

According to the authors, a deeper understanding of the interrelationships between sleep and pubertal maturation may provide new insights into the emergence of vulnerabilities for behavioral and emotional health problems in early adolescence, which could improve prevention and early intervention efforts.

Source: Kelly Wagner, American Academy of Sleep Medicine

A study in the Aug. 1 issue of the journal SLEEP indicates that children have an increased risk of developing obstructive sleep apnea (OSA) if they have at least one sibling who has been diagnosed with the sleep disorder.

Results indicate that after accounting for socioeconomic status, age, and geographic region, the sibling risk of pediatric OSA was extremely high, with a standardized incidence ratio of 33.2 in boys and 40.5 in girls who had at least one sibling with an OSA diagnosis. A total of 854 boys and 627 girls who were 18 years of age or younger had a first hospital diagnosis of pediatric OSA during the study period; there was no significant gender difference in the incidence rate of OSA among those with a sibling history of the sleep disorder.

According to principal investigator Danielle Friberg, MD, senior surgeon in the ENT department at Karolinska Institute in Stockholm, Sweden, early intervention can help prevent the potentially severe consequences of OSA in children.

“Early diagnosis and treatment is important to avoid complications such as learning difficulties, ‘failure to thrive,’ serious cardiovascular complications and even death,” said Friberg.

The individual study population was siblings born between 1978 and 1986, and the study included hospital data on all children in Sweden – 2.7 million individuals – during the study follow-up period between 1997 and 2004. Children 18 years of age and younger were divided into sibling groups, and the presence or absence of a primary hospital diagnosis of pediatric OSA during the follow-up period was determined for each individual. Then children were categorized as positive or negative for sibling OSA based on the presence of the disorder in at least one of their siblings. The incidence rates were computed using standardized incidence ratios with 95-percent confidence intervals. Reference groups were boys and girls with two or more unaffected siblings.

The study also examined the sibling risk of adenotonsillar hypertrophy, an important risk factor for pediatric OSA. A total of 13,656 boys and 11,648 girls had a first hospital diagnosis of hypertrophy of the tonsils, or hypertrophy of the adenoids and tonsils. The overall standardized incidence ratios for adenotonsillar hypertrophy among those who had at least one affected sibling were 4.53 for boys and 4.94 for girls. Although this familial risk was much lower than in the group with OSA, the authors report that the increase was highly significant and the numbers of children were much larger than in the OSA group.

The American Academy of Sleep Medicine reports that the prevalence of OSA is approximately two percent in otherwise healthy young children. OSA occurs when soft tissue in the back of the throat collapses and blocks the airway during sleep. Most children with OSA have a history of snoring that tends to be loud and may include obvious pauses in breathing and gasps for breath. Parents often notice that the child seems to be working hard to breathe during sleep.

According to the authors, the increased risks for both OSA and adenotonsillar hypertrophy could be an expression of genetic or shared environmental mechanisms. Recent genetic studies of both adult and pediatric patients with OSA indicate that genetic mechanisms do play an important role. Possible environmental factors include the increased medical awareness of sleep disordered breathing over time, both among parents and doctors.

The authors recommend that medical providers ask about sleep-related symptoms in siblings when children present with clinical signs or symptoms of OSA.

Source: Kelly Wagner, American Academy of Sleep Medicine