Severe ADHD hampers recovery from eating disorders

Patients with intense attention-deficit hyperactivity disorder (ADHD) symptoms have more trouble recovering from comorbid eating disorders (ED), according to a new study published in the European Eating Disorders Review.

“Better knowledge of the connection between ED and comorbid ADHD, both full-syndrome and subdiagnostic symptoms, is essential for understanding the interaction between the two conditions,” wrote corresponding author Nils Erik Svedlund, and colleagues at the Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.

Previous research indicated that people with ADHD are at greatest increased risk for binging/purging EDs like bulimia nervosa. Conversely, people with binging/purging EDs are at greatest risk for ADHD thus signifying a bidirectional relationship. Furthermore, ADHD symptoms in the anorexia nervosa binging/purging subtype are also more severe.

In addition, an increased severity of psychiatric comorbidity predicts poorer prognosis in bulimia nervosa and binge eating disorder. Nevertheless, the bearing of comorbid ADHD on ED outcomes has yet to be elucidated in a robust fashion.

“To explore if concurrent ADHD symptoms are important for treatment results in ED, we investigated how baseline ADHD symptoms affected the recovery rate in adult females 1 year after start of ED treatment,” the researchers wrote.

The team assessed 443 female subjects (average age: 27.5 years; average BMI 23.3) who presented to the Stockholm Centre for Eating Disorders, a large, highly specialized eating disorder clinic where patients can get help with a primary care referral. Researchers used prospectively gathered registry data spanning a full gamut of ED diagnoses, including results from the ADHD Self-Report Scale for Adults (ASRS-screener), demographic data, and ED symptom data. At a 1-year follow-up visit, they determined ED recovery follow-up visit.

More severe ADHD symptomatology (ie, higher ASRS scores) was significantly linked to decreased ED recovery at 1 year. As expected, inattentive symptoms of ADHD at baseline were specifically tied to nonrecovery, including binging, purging, and loss of control over eating. This finding implies that stimulants, which boost attention, could help patients with attention-deficit issues.

The team pointed out potential limitations of this study. Before the final analysis of 443 patients, 61% of the subjects in this study dropped out. Patients who dropped out of the study tended to be more depressed and shouldered increased social burden. Second, the team was unable to control for ADHD-esque conditions like borderline personality disorder or mental retardation, conditions which could thus serve as confounding variables. Third, the researchers were not privy to medication use by subjects during follow-up, and stimulant usage could have confounded results.

“Screening/diagnostic evaluation of ADHD in all loss of control over eating/binging/purging ED patients and studies of the effect of implementing ADHD-treatment strategies in this patient group are recommended,” the researchers concluded.