Is attention deficit hyperactivity disorder over-represented among HIV-seronegative boys with haemophilia?...

Haemophilia care providers report anecdotally that many boys under their care bear the diagnosis of attention deficit hyperactivity disorder (ADHD). This study investigated the hypothesis that ADHD is over-represented among boys with haemophilia. All the boys with haemophilia, aged 5-14 years, who receive their comprehensive care at our centre were solicited to participate in this study. Of the 78 eligible boys, 34 (44%) were successfully contacted and agreed to participate. All participants were HIV-negative on both serological and PCR-based assays. The presence of ADHD symptoms was established via a parent- and teacher-completed standardized rating instrument. On the parent-rating scale, 26% of the participants exceeded the cut-off for inattentive ADHD, 18% for hyperactive/impulsive ADHD, and 18% for combined. On the teacher rating scale, 4% of the participants exceeded the cut-off for inattentive ADHD, but no participants were rated as having extreme hyperactive/impulsive or combined ADHD symptoms. Retrospectively, 29% of the participants had previously been diagnosed with ADHD, all treated with stimulant medications. Of note, 38% of our participants were enrolled in special education programmes. All of the above were more common in boys with haemophilia compared with national controls. A chart review of non-participating patients from the same clinic suggested that sampling bias is unlikely to account for these differences. These results provide the first empirical evidence that ADHD may be over-represented among boys with haemophilia.