ADHD: An Associate of Bulimia Nervosa?

Attention-deficit/hyperactivity disorder (ADHD) is estimated to affect 5% to 10% of children and 4% of adults. Impulsivity is one of the key features of ADHD and also is an indicator of poor prognosis for persons with bulimia nervosa (BN). Could there be an association between ADHD and BN?

To answer this question, Craig B. H. Surman, MD and two colleagues at Massachusetts General Hospital, Boston, systematically identified rates of BN in individuals with and without ADHD among four groups, two large groups of children (522) and two large groups of adults (742) (J Clin Psychiatry 2006; 67:351).

An association is found

Among the two large pediatric groups, 1% of girls with ADHD and none without ADHD met diagnostic criteria for a history of BN. The ages at onset of BN for the two girls with ADHD and BN were 12 years and 14 years, respectively. No boys with or without ADHD had a diagnosis of BN.

Among the adult groups, a significantly higher proportion of women with ADHD met diagnostic criteria for a history of BN than did gender-matched control subjects (12% vs. 3% in one group, and 11% vs. 1% in the second group). The rates of BN were negligible among men with or without ADHD.

What does this mean?

The authors note that this is the first evaluation of the comorbidity between ADHD and BN. Their results show that BN was selectively overrepresented in women with ADHD but not in girls with this disorder. According to the authors, this suggests that symptoms of BN emerge in adulthood in women with ADHD. However, they also note that since BN commonly appears in late adolescence, the ability to fully assess BN was limited because only 20% of the girls with ADHD and 26% of the control girls in the study were 15 years of age or older.

Although the reasons for the overrepresentation of BN in women with ADHD remain unclear, there are several possible explanations, according to the authors. A factor common to both ADHD and BN may have mediated the apparent association between the two conditions in the authors’ clinical samples of adult women.

Also, common predisposing environmental or familial factors could have contributed to the manifestation of both conditions in persons with ADHD. For example, high rates of major depression and substance abuse have been described in studies of persons with BN (Clin Psychol Rev 2003; 23:57) and in subjects with ADHD.

Treatment with psychostimulants

In a small study of six patients with comorbid ADHD and BN, all patients reported complete abstinence from binge eating and purging after treatment with psychostimulants. All remained within a healthy weight range (J Women’s Health 2005; 14:345).