Washington: Although you think you're in good shape, you may be at serious risk from the inside, says a study of atypical anorexia. Traditionally, individuals had to be below 85% of their ideal body weight to be diagnosed with anorexia nervosa, a disorder characterized by restrictive eating, over-exercise, distorted body image, and intense fear of weight gain.
But in 2013, a new category of eating disorder was formally recognized: atypical anorexia nervosa.
Individuals with this condition meet all other diagnostic criteria for anorexia nervosa but have normal body weight. "This group of patients is under-recognized and undertreated," said senior study author Neville Golden, MD, professor of pediatrics at the Stanford School of Medicine.
"Our study showed that they may be as clinically and psychologically ill as underweight patients with anorexia nervosa," Golden added. The study published in Pediatrics shows that rapid and large weight loss is the best predictor of medical and psychological problems in patients with atypical anorexia, not body weight at diagnosis.
Dangerously low heart rate and blood pressure, as well as severe electrolyte imbalances and psychological problems, are common in patients with atypical anorexia whose weight is within the normal range, the study found.
"The larger context is that over the past 30 years, the prevalence of obesity in adolescence has quadrupled, and adolescents are being instructed to lose weight without having the tools to do so in a healthy way," said Golden.
Obese adolescents who engage in unhealthy behaviors – such as severe dietary restriction and extreme exercise – may initially be praised for weight loss or instructed not to worry about eating disorder problems because they are underweight.
"When they see us, they have lost a tremendous amount of weight, their vital signs are unstable and need to be hospitalized," said Golden. The researchers used statistical modeling to determine which factors predicted disease severity. The amount, speed and duration of weight loss were associated with worse illnesses; Body weight at diagnosis was not, they found.
"If a patient was obese, the goal is not to regain lost weight," Golden said, adding that a mix of metabolic, hormonal and psychological measures may be needed to define a healthy weight. "If someone gains a little weight, regains menstruation and is doing well socially, emotionally and cognitively, this may indicate that they are in a recovery place," he said.