BY: Melissa Munn-Chernoff, PhD

DATE: September 3, 2015

Although psychiatric disorders and their symptoms can occur at any time in someone’s life, adolescence is a high-risk developmental period for the onset of many problem behaviors including substance use and psychiatric disorders such as depression. Eating disorders and their symptoms are no exception. In some ways, this makes changes that emerge from societal pressures like peer influences, which can lead to unhealthy thoughts and behaviors about oneself. Therefore, it may not be surprising that many psychiatric disorders and their symptoms tend to occur together and can unfortunately persist for some time past adolescence.

An article published by Micali and colleagues in the August issue of the Journal of the American Academy of Child and Adolescent Psychiatry examined the association between past year eating disorder diagnoses/symptoms and psychiatric disorders, substance use, and weight status approximately 2 years later. The authors included information from 5,000-6,000 boys and girls from the United Kingdom. The boys and girls participated in the study up to 3 different times—when they were 14, 16, and 18 years old. The goal of the study was to examine whether eating disorder diagnoses/symptoms predicted the later onset of psychiatric disorders, substance use, and weight status.

The eating disorders were examined when adolescents were 14 and 16 years old. They included: anorexia nervosa, bulimia nervosa, binge-eating disorder, purging disorder, subthreshold bulimia nervosa (monthly instead of weekly binge eating and purging), subthreshold binge-eating disorder (monthly instead of weekly binge eating), and other specified feeding and eating disorder (OSFED) (monthly or less than monthly binge eating, purging, excessive exercising, or fasting). Questions about psychiatric disorders and substance use were asked at ages 16 and 18 years. They included: anxiety disorder, depression, drug use in the past year, binge drinking (having 6 or more alcoholic beverages on a single occasion at least monthly in the past year), and deliberate self-harm. Weight status was also asked when the adolescents were 16 and 18 years old, and individuals were grouped as underweight, overweight, or obese.

Key findings about the prevalence of eating disorders are:

• The prevalence of eating disorders was 2 to 3 times higher at age 16 than age 14: 18.95% of adolescents at age 14 and 36.87% of adolescents at age 16 reported any eating disorder in the past year.
• In general, anorexia nervosa was more prevalent than bulimia nervosa, binge-eating disorder, and purging disorder in both girls and boys. However, purging disorder was the most prevalent eating disorder in girls at age 16 (2.45%).

The authors then examined whether eating disorders/symptoms at age 14 predicted psychiatric disorders, substance use, and weight status at age 16. They also explored whether eating disorders/symptoms at age 16 predicted psychiatric disorders, substance use, and weight status at age 18. The authors took into account the age, gender, mom’s education level (as an indirect measure of socio-economic status), and the number of pregnancies the mom had, as well as prior depression, anxiety, and substance use in the adolescents in their analyses. Adjusting for psychiatric disorders and substance use is important to make sure that earlier depression, for example, is not solely responsible for any observed association in later adolescence. Here’s what they found:

• Anorexia nervosa in adolescence predicted depression and anxiety disorders approximately 2 years later. Individuals with anorexia nervosa at either age 14 or 16 were also more likely to be underweight at age 16 or 18 than those without anorexia nervosa.
• Boys and girls with bulimia nervosa were more likely to report depression, anxiety disorders, and drug use in the past year, and deliberate self-harm 2 years later. These adolescents were also more likely to be obese at a later assessment than adolescents without bulimia nervosa.
• Binge-eating disorder was associated with later onset of depression, anxiety disorders, and drug use in boys and girls. Similar to bulimia nervosa, adolescents with binge-eating disorder were also more likely to be obese at a later assessment than adolescents without binge-eating disorder.
• Purging disorder and subthreshold bulimia nervosa predicted later onset of anxiety disorders, drug use, and deliberate self-harm in both genders. There was no association with weight outcome 2 years later.
• In boys and girls, subthreshold binge-eating disorder and OSFED were associated with later onset of depression, anxiety disorders, drug use, and deliberate self-harm. OSFED was significantly associated with being overweight or obese at the next assessment.
• There were no associations between any of the eating disorders and binge drinking 2 years later.

This study highlights the fact that eating disorders are serious illnesses, even in adolescents, that can lead to other psychiatric disorders and substance use later in adolescence. They can also predict one’s weight status a couple years later. If we can prevent eating disorders from occurring during this important period in one’s life, or at least treat the disorders early on, then we may also be able to alleviate or reduce the risk for other problem behaviors that may result from the eating behaviors in the first place.

Reference

1. Micali, N., Solmi, F., Horton, N.J., Crosby, R.D., Eddy, K.T., Calzo, J.P., Sonneville, K.R., Swanson, S.A., and Field, A.E. (2015). Adolescent eating disorders predict psychiatric, high-risk behaviors and weight outcomes in young adulthood. Journal of the American Academy of Child & Adolescent Psychiatry, 54, 652-659.