SEATTLE — Sizable proportions of adolescents progress along a spectrum of eating-disordered behavior over time, highlighting the importance of early detection and intervention, Diann M. Ackard, Ph.D., said at an international conference sponsored by the Academy for Eating Disorders.
Dr. Ackard, a psychologist in private practice in Golden Valley, Minn., and her colleagues assessed the stability of eating disorder classifications among a population-based sample of adolescents in Project EAT (Eating Among Teens). In the project, the same adolescents completed surveys about eating behaviors and body image in 1999 and again in 2004, and the survey items were mapped onto DSM-IV criteria.
Analyses were based on 2,516 adolescents in middle school or high school at the first assessment, Dr. Ackard reported at the conference, which was cosponsored by the University of New Mexico. Those in middle school were a mean age of 12.8 years and those in high school were a mean age of 15.8 years in 1999. Fifty-five percent were female.
At the first assessment, 10% of the adolescents met full-threshold criteria for a clinical eating disorder (anorexia nervosa, bulimia nervosa, or binge eating disorder), 39% had some subthreshold symptoms (compensatory behaviors or body image disturbance), and 50% were asymptomatic.
Five years later, considerable flux in the eating disorder groups was evident, Dr. Ackard reported. Among female adolescents who were asymptomatic at the first assessment, 63% remained so at follow-up—but 36% had developed symptoms and 1% had developed full clinical disorders. About 61% of those who initially had some symptoms still had them; another 37% had improved, becoming asymptomatic, but 3% had worsened and developed clinical disorders.
Among male adolescents who were asymptomatic at the first assessment, 74.5% remained so at the second assessment, but 25% had developed some symptoms and 0.4% had developed clinical disorders. And 38.8% of those who initially had some symptoms still had them; an additional 59.9% no longer had any symptoms, but 1.4% had progressed to a clinical disorder. Finally, all of the male adolescents who initially had a clinical disorder had improved to the point of having only some symptoms.
The study's good news, Dr. Ackard said, is that after 5 years, most asymptomatic youth (68.9% overall) remained symptom free, most with subclinical symptoms (52.4%) did not worsen to full clinical eating disorders and in fact 45.2% became asymptomatic.
In addition, most with clinical eating disorders improved to having only some subclinical symptoms (74%) or no symptoms (18%), said Dr. Ackard, also of the University of Minnesota, Minneapolis, and a research scientist at the Eating Disorders Institute at Park Nicollet Methodist Hospital, St. Louis Park, Minn.
On the flip side, some asymptomatic adolescents worsened to the point of having subclinical symptoms (30%) or clinical disorders (1%), others with symptoms progress to clinical disorders (2%), and a considerable proportion with clinical disorders still had them 5 years later (9%).
She reported that she had no conflicts of interest in association with the study.
Among females who were asymptomatic at the first assessment, 36% had developed symptoms. DR. ACKARD