EDNOS: A Catch-All Diagnosis?

Binge eating followed by compensatory behaviors such as self-induced vomiting and use of laxatives and diuretics provides the most common symptoms of full- and subthreshold eating disorders. Such behaviors, with or without binge eating, form the basis for a diagnosis of eating disorders not otherwise specified (EDNOS).

According to Dr. Dawit Shawel Abebe and colleagues of the Norwegian Social Research organization, the broad category identified as EDNOS has become a catch-all category for patients, and needs to be better defined. That is, future diagnostic categories in the DSM-5 may need to be better defined to reflect combinations of binge eating with compensatory behaviors, whether these include purging or not. According to the researchers, those who purge are at special risk.

Dr. Abebe and colleagues gathered data from a Norwegian national representative longitudinal study, “Young in Norway,” which followed individuals from 14 to 34 years of age and was conducted at four time points: 1992, 1994, 1999, and 2005 (BMC Public Health 2012; 12:32). The study was conducted in 67 representative schools in Norway and sampled thousands of students 12 to 20 years of age, in grades 7 to 12. At each of the 4 time points, students who responded to the earlier study were invited to participate once more, and a 67% overall response rate was recorded.

At each point, students completed self-report questionnaires that examined items such as binge eating and compensatory behaviors (Bulimic Investigatory Test, Edinburgh, or BITE), eating problems (the BITE test and the Eating Attitude Test12), satisfaction with appearance, depressive symptoms (Depressive Mood Inventory), anxiety symptoms (Hopkins Symptom Checklist), and measures of general self-worth, alcohol consumption, relationship with parents, self-concept (Rosenberg’s Stability of Self scale), social support, and loneliness. Body mass index (BMI, kg/m²) was computed from self-reported measures of height and weight.

Females were at higher risk

The researchers found that subclinical groups of individuals with differing combinations of eating disorder symptoms showed distinct age- and gender-related trends. For example, females were at significantly higher risk for purging behaviors than were males. The prevalence of binge eating and compensatory behaviors in females and compensatory behaviors in males gradually declined with the transition from adolescence to young adulthood. Individuals with subclinical forms of eating disorders differed significantly on measures of general eating and psychosocial problems.

Purging emerged as the most serious type of behavior, compared with compensatory behaviors, binging-compensatory behaviors, and non-purging compensatory behaviors. Individuals who purged, mostly by using self-induced vomiting, had significantly higher levels of appearance dissatisfaction, anxiety and depressive symptoms, drank larger amounts of alcohol, and were more unstable and lonelier than other participants. For both males and females, the prevalence of compensatory behaviors decreased from age 14 to 16 to 23 years and over. However, for binge eating, a significant decrease was found only for females, whose binge eating also declined more markedly over time than did that of males.

The authors concluded that a substantial proportion of teens report binge eating and using inappropriate weight control methods. As they transition to young adulthood, the risk declines somewhat. According to the authors, early preventive interventions could potentially decrease the likelihood that the inappropriate behaviors will progress to full-threshold eating disorders.