New info on eating disorders in two Stanford/Packard children's studies

December 3, 2006

One study, to be published in the December issue of Pediatrics, is the first to confirm that pro-eating disorder Web sites may promote dangerous behaviors in adolescents with eating disorders.

One study, to be published in the December issue of Pediatrics, is the first to confirm that pro-eating disorder Web sites may promote dangerous behaviors in adolescents with eating disorders. The second, which appears in the December issue of the Journal of Adolescent
Health, indicates that pre-teens with eating disorders tend to lose weight more quickly than adolescents with the condition and weigh comparatively less at diagnosis. Packard Children's adolescent medicine and eating disorder specialist Rebecka Peebles, MD, and
Jenny Wilson, a Stanford medical student, collaborated on both studies.

"If parents wouldn't let their kids go out to dinner or talk on the phone with someone they don't know, they should ask themselves what their child might be up to on the computer," Peebles, a medical school pediatrics instructor, said of the findings in the first study. She pointed out that, unlike adults, teens make few distinctions between "real" friends and people they know only online.

In this study, Peebles and Wilson surveyed families of patients who were diagnosed at Packard Children's with an eating disorder between 1997 and 2004. Seventy-six patients, who were between the ages of 10 and 22 at diagnosis, and 106 parents returned an anonymous survey
asking about Internet use - including parental restrictions on it - and health outcomes.

About half of the patients surveyed said they had visited Web sites about eating disorders. Ninety-six percent of teens who visited pro-eating disorder Web sites reported learning new dieting and
purging techniques. The researchers also found that pro-eating disorder site visitors tended to have a longer duration of disease, spent less time on schoolwork and spent significantly more time
online each week than did those who never visited the sites.

Even those sites ostensibly dedicated to helping people recover from eating disorders (pro-recovery sites) aren't harmless. Nearly 50 percent of patients visiting such sites reported learning about new
methods to lose weight or to purge.

"Parents and physicians need to realize that the Internet is essentially an unmonitored media forum," said Peebles. "It's just not possible to completely control the content of an interactive site."

While about 50 percent of parents were aware of the existence of pro-eating disorder sites, only 28 percent had discussed these sites with their child. Fewer still, only about 20 percent, reported
placing limits on either the time their child spent online or on the sites they visited.

Parents aren't the only ones who may not recognize trouble brewing. Peebles and Wilson found in their second study that younger eating disorder patients may be at risk for more rapid weight loss than adolescents and frequently have atypical presentations that may make diagnosis more difficult.

"We were very surprised and concerned to find that younger patients lost weight significantly faster than adolescent patients," said Peebles, who pointed out that growth before puberty is critical to
future development. "Children should be growing rapidly during pre-adolescence. But these kids had not only stopped gaining, they'd even lost weight."

Adult-specific diagnostic criteria for such eating disorders as anorexia and bulimia muddy the issue, said Peebles, by referring to missed menses and ideal body weight percentages, neither of which are applicable to prepubescent girls who may have already stunted their height by denying themselves needed calories.

"They may not be less than 85 percent of their ideal body weight according to a standard growth chart," she said, "but it's very possible that, without their eating disorder, they would have been
significantly taller and heavier." It's also sometimes difficult to tell whether young children display the same kind of disordered body image disturbance as older children with eating disorders, who often proclaim themselves "fat" or "disgusting."

"Young kids may truly not know why they don't want to eat," said Peebles. "They just don't want to be bigger." As a result, more than 60 percent of patients younger than 13 are diagnosed with an "Eating Disorder Not Otherwise Specified," or EDNOS.

Other surprises of the research include the facts that younger patients were more likely to be male than those older than 13, and that one in five patients younger than 13 had experimented with
vomiting as a weight-loss technique.

"Pediatricians and parents shouldn't think of weight loss, or even lack of weight gain in a pre-teen, as a phase," cautioned Peebles. "If a child expresses wanting to lose weight, take it seriously."

Source: Stanford University Medical Center