(09-20) 08:05 PDT SAN FRANCISCO -- When adolescents are hospitalized with anorexia nervosa, feeding their malnourished young bodies is of urgent importance. On the complicated path to recovery, gaining weight is a critical step.
But how hospitals approach that first step, called refeeding, has in recent years been subject to rethinking.
Now a quartet of studies to be published in the November issue of the Journal of Adolescent Health offers evidence in favor of a new approach - and suggests an emerging shift in the way hospitals approach treating the disorder.
Anorexia, an eating disorder typified by relentless pursuit of thinness, affects about 1 percent of adolescent girls in the United States, by some estimates. Weight gain is crucial in reversing medical complications of anorexia, such as confusion, sensitivity to cold and even failing organs, and in enabling the difficult psychological recovery that must accompany a physical one.
In refeeding, calories traditionally are doled out with caution, new patients starting with a low number that is then gradually increased. Pushing too much, too quickly could be dangerous, so the old wisdom goes, the sudden surge of nutrients putting a malnourished body at risk for a potentially fatal metabolic imbalance.
The standard is rooted in post-World War II studies of Americans held by the Japanese as prisoners of war and reinforced in clinical guidelines from organizations like the American Psychiatric Association. It is typical for initial calorie intake to begin somewhere around 1,200 calories a day, about half of the recommended daily intake for an average healthy teenager.
Then in 2011, researchers at UCSF Benioff Children's Hospital issued a challenge to that long-standing standard, suggesting instead that the "start low, go slow" method was inefficient, unnecessary and out of date. They proposed instead that most patients can start at much higher calorie levels.
"Those old guidelines are based on consensus, but they are not based on clinical evidence," said Andrea Garber, lead author of the 2011 study and an associate professor of pediatrics in UCSF's adolescent medicine division.
And, now, a new study from UCSF, published online Wednesday, took the initial findings one step further, enrolling a group of adolescents in a higher-calorie diet to compare with the first study's low-calorie diet. The new group gained weight faster and its members were released from the hospital sooner, with no cases of refeeding syndrome.
The study compared 56 adolescents, some starting at an average of about 1,800 calories while the other participants started at about 1,100.
The main difference: Those in the higher-calorie group left the hospital an average of six days sooner, were able to eat more and more each day and, therefore, gained weight at a faster clip. The old approach, the 2011 paper found, failed to produce necessary weight gains in the first days of hospitalization and resulted in lengthy hospital stays.
Another study from Stanford reached similar conclusions in an examination of electronic medical records from 310 adolescents admitted to Stanford's Lucile Packard Children's Hospital.
A third study examined a more aggressive refeeding program at a Canadian children's hospital and determined it was "effective, efficient and safe." Yet another, also from Canada, found retrospectively that a higher-calorie approach achieved fast, safe results when feeding patients with a feeding tube.
"I think what's really important here is before, there really hasn't been much research on how to refeed people with anorexia," said Dr. Walter Kaye, director of UC San Diego's eating disorder program, who was not associated with the studies.
Road to recovery
The new approach allowed Alexis McIsaac, to get out of the hospital and on the path to recovery sooner.
McIsaac, 17, of Petaluma was in and out hospitals, including UCSF's eating disorder program, five times between October 2011 and January 2013.
The experience was grueling. Eating again made her body reel and her emotions surge.
"It was one of the hardest things I've done," she said. "There's this voice in your head telling you not to eat."
But she did eat, the higher-calorie prescription no more a challenge than eating any amount of food would have been. Her body began to heal. She left the hospital stabilized, ready to tackle the months of work in therapy and at home that helped put her where she feels she is now, in grasp of recovery.
"UCSF didn't cure my eating disorder, but it did save my life," she said.
The new UCSF study only examined patients that were "moderately" malnourished. The Stanford study, though, looked at those who were severely malnourished and found that while risks of refeeding syndrome depend on the degree of malnutrition, they had nothing to do with the particular number of calories consumed.
At UCSF, the higher-calorie approach was first introduced in 2008. Since the 2011 study, increasingly other hospitals, like Lucile Packard, have begun to buck the standard.
"With this swirl of new studies," said Dr. Neville Golden, chief of adolescent medicine at Lucile Packard, "I think we will be able to change the existing recommendations out there."