Celiac disease is markedly overrepresented among patients presenting with attention deficit/hyperactivity disorder (ADHD), and a gluten-free diet significantly improved ADHD symptoms in patients with celiac disease, according to the results of a recent study.
“The results of this study suggest that … untreated celiac disease may predispose patients to mental and behavioral disorders such as ADHD. The results also indicate that celiac disease, which has a prevalence rate of 4%, should be included in the list of symptoms of ADHD,” the researchers wrote in the study, which was published in The Primary Care Companion for CNS Disorders. The lead author of the study was Helmut Niederhofer, MD, PhD, of the department of child psychiatry at the Psychiatric Hospital of Rodewisch in Germany.
The researchers cited previous research showing that a gluten-free diet improved mood and behavioral disturbances in some patients, possibly with concomitant elevations in plasma concentrations of tryptophan, which is a precursor of serotonin.
“Impaired availability of tryptophan in the central nervous system predisposes to disturbances in central serotonergic function associated with depressive disorders and aggression dysregulation. Significantly lower levels of whole blood tryptophan have been found in prepubertal children with a recent history of a suicide attempt compared with normal controls,” they wrote.
Niederhofer and colleagues enrolled 67 subjects aged 7 to 42 years (mean=11.4 years) with ADHD in the study in South Tyrol, Italy, from 2004 to 2008. They used Hypescheme, an operational criteria checklist that incorporates DSM-IV and ICD-10 criteria, to assess ADHD-like symptomatology.
The blood serum levels of symptomatology subjects were assessed for possible celiac disease by examining antigliadine and antiendomysium antibodies. A gluten-free diet was initiated for at least six months in the 10 celiac disease-positive patients with ADHD.
“After initiation of the gluten-free diet, patients or their parents reported a significant improvement in their behavior and functioning compared to the period before celiac diagnosis and treatment, which was evident in the overall mean score on the Hypescheme questionnaire (t = 4.22, P = .023),” the authors wrote.
“A limitation of the study is that the sample size was quite small. Nevertheless, the results strongly suggest that a diagnosis of celiac disease should be included in the ADHD symptom checklist to avoid unnecessary stimulant treatment. Further research is urgently required.”
SourceAssociation of Attention-Deficit/Hyperactivity Disorder and Celiac Disease: A Brief Report [The Primary Care Companion for CNS Disorders]