Doctors can miss eating disorders in teens who have been obese

The news is not always all good when obese teenagers lose weight. Such young people seem to be at risk for developing eating disorders that slip the attention of health professionals, scientists report.

“Physical complications of semistarvation and weight loss, which are red flags in a low-weight individual, are often misdiagnosed in these patients,” and referrals for eating disorder treatment get delayed as a result, the scientists wrote in this week’s issue of the journal Pediatrics.

Forty-five percent of the patients in their eating disorders clinic in the last year were adolescents with a history of obesity, wrote the scientists, who are from the Mayo Clinic College of Medicine.


In the journal, the scientists describe two teenagers in whom “despite regular medical check-ups and obvious signs of malnutrition, eating disorders were not identified as such and consequently worsened.” Both developed their eating disorders in the course of efforts to lose weight.

The problem comes amid nationwide concern over childhood obesity, which the researchers said affects 17% of children and adolescents. At the same time, they wrote, at least 6% have an eating disorder such as bulimia or anorexia nervosa. Fifty-five percent of high school girls and 30% of boys say they have had symptoms of disordered eating, which include fasting, using diet pills and vomiting to lose weight.

Daniel, 14, had lost about 80 pounds over two years after many years of being “well above” his peers in body mass index – a measure of weight and height often used to assess obesity. He began losing weight by eating healthfully and exercise but quickly developed severely restrictive habits. Daniel himself, the researchers wrote, did not recognize his situation, and although for most of his life doctors had focused on his weight, “during the 13 medical encounters that took place when he was losing weight, there was no discussion of concerns regarding weight loss.”

Daniel’s symptoms included difficulty concentrating, social withdrawal, cold intolerance, fatigue and chest pains.

The second teenager, 18-year-old Kristin, tried several diets and by 14 weighed about 170 pounds. At that point she began a diet and running seven miles a day. She went from the 97th percentile to the 10th percentile in three years. But after the first year, she saw a doctor for dizziness, lack of menstruation and other issues. In that meeting and others, she was given various kinds of advice but not referred for eating disorder treatment.

At visits to doctors, the teens were often thought to have various maladies other than eating disorders, despite parents’ concerns that were on the money.

Heavy teenagers are not only at risk for binge eating, the scientists said. In one study of more than 100 people with anorexia nervosa – characterized by severely restricted calorie intake, sometimes to the point of death—the majority had a history of obesity.

The scientists wrote that an eating disorder should be considered based on the patient’s deviation from the pattern of growth. They said, “Any weight loss, even if it takes a child from overweight to the ‘average’ range, should prompt eating disorder screening.”

As well, even if the patient is not low-weight, issues related to eating disorders – excessive exercise, extreme dietary restriction, binging and purging and other behaviors — should be red flags, the scientists wrote.

@mmacvean on Twitter