Breathing problems or a chronic lack of sleep early in life may double the risk that a child will be obese by age 15, according to research published Thursday in The Journal of Pediatrics.
December 11, 201410:54 AM ET
ALISON BRUZEK
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Breathing problems or a chronic lack of sleep early in life may double the risk that a child will be obese by age 15, according to research published Thursday in The Journal of Pediatrics.
Childhood obesity has been linked before with the number of hours a kid sleeps each night. But other early problems with nighttime breathing — like snoring, or the more serious sleep apnea — also seem to be predictive of significant weight gain among children, according to the research.
It's the first study to look at both sleep duration and breathing problems as separate risk factors for obesity, says Karen Bonuck, professor of family and social medicine at the Albert Einstein College of Medicine of Yeshiva University and lead author.
To examine sleep habits and how they might predict a child's body mass index, Bonuck and her colleagues used the Avon Longitudinal Study of Parents and Children, which tracked 1,900 children in England for 15 years.
They found that children who had multiple sleeping problems were twice as likely to be obese by age 7, 10 or 15 years, compared with those who had no problems. At age 15, 9.7 percent of teens with no sleep problems were obese, compared with 18.3 percent of those with multiple sleep problems.
In addition, children who slept less than 10 hours per night at ages 5 and 6 years were more likely to be obese at age 15.
While the study could only confirm an association, not causality, it makes sense that children who don't get enough solid sleep are tired, and may eat more, sleep scientists say. "Some of this actually might be related to certain hormones that regulate appetite," says Dr. Rakesh Bhattacharjee, a pediatric sleep medicine specialist at the University of Chicago Medicine Comer Children's Hospital.
Another theory holds that poor sleep quality or short duration may cause stress on the body that leads to inflammation.
Though many questions about sleep's effects and mechanisms remain, all agree it's important, especially in growing children, Bonuck says. Newborns should get around 16 to 18 hours per day, according to the Centers for Disease Control and Prevention, and preschoolers 11 to 12 hours.
Parents should look for early signals, Bonuck says. Noisy or halted breathing at night could mean something serious is amiss. "Watch your child," she says. "Does she or he snore more than three times a week?"
The American Academy of Pediatrics recommends that all children who snore regularly be screened for sleep apnea — partly because it's easier to prevent childhood obesity than to treat it. "As Benjamin Franklin once said, 'An ounce of prevention is worth a pound of cure,' " Bonuck says. "Pun intended."
Evidence Mounts for Poor Sleep/Pediatric Obesity Connection
Sleep-related breathing problems and chronic lack of sleep may each double the risk of a child becoming obese by age 15, according to new research from Albert Einstein College of Medicine of Yeshiva University. The good news is that both sleep problems can be corrected. The study, which followed nearly 2,000 children for 15 years, published online in The Journal of Pediatrics.
“In recent years, lack of sleep has become a well-recognized risk for childhood obesity,” said Karen Bonuck, Ph.D., professor of family and social medicine and of obstetrics & gynecology and women’s health at Einstein and lead author on the paper. “Sleep-disordered breathing, or SDB, which includes snoring and sleep apnea, is also a risk factor for obesity but receives less attention. These two risk factors had not been tracked together in children over time to determine their potential for independently influencing weight gain. Our study aimed to fill in that gap.”
Dr. Bonuck and her colleagues used data collected on 1,899 children by the Avon Longitudinal Study of Parents and Children (ALSPAC) based in Avon, England. ALSPAC collected parent questionnaire data on both child sleep duration and SDB symptoms from birth through 6.75 years and child BMI data from research ALSPAC clinics.
Sleep-disordered breathing
The researchers found that children with the most severe SDB had the greatest risk for obesity. Those children who fell into the “worst case” SDB category were twice as likely to become obese by 7, 10 and 15 years of age, compared to the asymptomatic group. Children considered “worst case” scored highest for SDB symptoms of snoring, sleep apnea or mouth-breathing.
Children whose SDB peaked later, around 5 to 6 years old, fared better but still had a 60 to 80 percent increased risk of becoming obese. Overall, one-fourth of children in this population-based cohort had an increased statistical risk of obesity that arose from SDB symptoms experienced earlier in life. Obesity was defined as BMI greater than the 95th percentile for age and gender, according to the International Obesity Task Force.
Sleep duration
With respect to sleep duration, children with the shortest sleep time at approximately 5 and 6 years of age had a 60 to 100 percent increased risk of being obese at 15 years. Children with short sleep duration at other ages saw no significant increase in risk. (In this study, children with short sleep duration were those who, in any given age group, slept less than 90 percent of their peers. For those aged 5 and 6 years old, this was 10.5 hours a night or less.)
Interestingly, SDB and lack of sleep were equally strong risk factors for obesity, but their effects were independent of each other. The researchers looked for associations between short-sleep-duration children and SDB children across all age groups included in the study but did not find clustering, i.e., there was little evidence that children with one risk factor were more likely to also be affected by the other. The study did not analyze whether children affected by both of the sleep-related risk factors were at greater risk for obesity than were children who had just one risk factor.
