BY: Melissa Munn-Chernoff, PhD

DATE: December 11, 2015

A recent article published online in the Journal of the American Academy of Child & Adolescent Psychiatry examined the association between high achievement in school and risk for eating disorders in nearly 900,000 males and 900,00 females born in Sweden between 1972 and 1990. The authors also gathered information about whether these individuals had first-cousins, half-siblings, and full-siblings in the sample, as well as whether there were any identical twins, to determine if familial factors (which include genetic risks and/or environmental risks shared by family members) impacted the association. The goal of the study was to not only see whether there was an association between school achievement and eating disorders in adolescence and young adulthood, but also whether this high achievement in school could be a “causal” factor for the development of anorexia nervosa and bulimia nervosa, or at the very least, was due to non-familial risk factors.

Some of the highlights from the article included:

• The mean age of diagnosis was similar in males and females: 20.7 years for anorexia nervosa and 23.5 years for bulimia nervosa.
• High achievement in school was significantly associated with risk for anorexia nervosa in both males and females.
• High achievement in school was significantly associated with risk for bulimia nervosa in females only.
• These associations were not accounted for by parental education or year of birth.
• In addition, the association between high achievement in school and anorexia nervosa was strongest closer to the graduation year, particularly for males. On the other hand, the association between high achievement in school and bulimia nervosa remained the same over time in both males and females.
• There was little evidence that high achievement in school was a “causal” factor in the development of eating disorders. The association between school achievement and risk for anorexia nervosa and bulimia nervosa may be best explained by genetic and/or environmental factors shared by family members.

What may be the genetic or environmental factors that contribute to the association between high achievement in school and eating disorders? The authors suggest that family values or role modeling may be important. Personality traits, such as perfectionism, which are also influenced by genetic and environmental factors, could also play a role. Nevertheless, it is highly likely that the genetic and environmental factors contributing to the school achievement and eating disorder association would interact with each other. Examining these additional characteristics will provide important clues into why individuals with high achievement in school are at increased risk for anorexia nervosa and bulimia nervosa.

Reference:

Sundquist, J., Ohlsson, H., Winkleby, M.A., Sundquist, K., Crump, C. (in press). School achievement and risk of eating disorders in a Swedish national cohort. Journal of the American Academy of Child & Adolescent Psychiatry. doi: 10.1016/j.jaac.2015.09.021.