Obese teenagers who don't get the proper amount of sleep may have disruptions in insulin secretion and blood sugar (glucose) levels, say pediatric researchers. Their study suggests that getting a good night's sleep may stave off the development of type 2 diabetes in these adolescents.
"We already know that three out of four high school students report getting insufficient sleep," said study investigator Dorit Koren, M.D., a pediatric endocrinologist at The Children's Hospital of Philadelphia. "Our study found to keep glucose levels stable, the optimal amount of sleep for teenagers is 7.5 to 8.5 hours per night." She added that this is consistent with research in adults showing an association between sleep deprivation and increased risk of type 2 diabetes.
The study appears online today in the journal Diabetes Care.
The researchers studied 62 obese adolescents with a mean age of 14 years at The Children's Hospital of Philadelphia. Over one and a half days, the children, who were white, African American and Hispanic teenagers, underwent glucose testing and an overnight sleep study. In addition to measuring total sleep time, the scientists studied "sleep architecture," analyzing stages of sleep such as slow-wave "deep" sleep and rapid eye movement (dream) sleep.
The optimal sleep duration was neither too little nor too much, said Koren; both insufficient and excessive sleep were linked to higher glucose levels. While sleep stages did not predict glucose levels, lower duration of N3 ("deep" sleep) correlated with decreased insulin secretion.
The current study was the first to associate sleep duration with glucose levels in children and to report a link between N3 sleep and insulin secretion.
"Reduced insulin secretion may lead to the higher glucose levels that we found in subjects who had insufficient sleep," said Koren. "We will seek to confirm these findings with home-based studies of sleep patterns in obese teenagers. In the meantime, our study reinforces the idea that getting adequate sleep in adolescence may help protect against type 2 diabetes."
Funding support for the study came from the Pennsylvania State Tobacco Settlement Fund and the National Center for Research Resources, (part of the National Institutes of Health). Koren's co-authors were Lorraine E. Levitt Katz, M.D., Paul R. Gallagher, M.A., Robert I. Berkowitz, M.D., and Lee J. Brooks, M.D., all of Children's Hospital; and Preneet C. Brar, M.D., of New York University School of Medicine. Koren, Levitt Katz, Berkowitz and Brooks are also from the Perelman School of Medicine at the University of Pennsylvania.
"Sleep Architecture and Glucose and Insulin Homeostasis in Obese Adolescents," Diabetes Care, published online Sept. 20, 2011, to appear in November 2011 print edition.
About The Children's Hospital of Philadelphia: The Children's Hospital of Philadelphia was founded in 1855 as the nation's first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children's Hospital has fostered many discoveries that have benefited children worldwide. Its pediatric research program is among the largest in the country, ranking third in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 516-bed hospital recognition as a leading advocate for children and adolescents. For more information, visit http://www.chop.edu.