Attention Deficit Predicts Intellectual Functioning in Children with Neurofibromatosis Type 1

Aims. Attention deficit hyperactivity disorder (ADHD) is one of the most frequent neurocognitive impairments in neurofibromatosis type 1 (NF1) and a well-known risk factor for intellectual dysfunction in general. Since NF1 is per se associated with intellectual difficulties, this comorbidity may be crucial for the cognitive development of affected patients. In our study, we investigated if attention deficits are associated with intellectual functioning in NF1 and if children with NF1 plus ADHD differ in their intellectual and attention profiles from children affected by NF1-only or ADHD only. Methods. 111 children aged between 6 and 12 years (53 NF1 plus ADHD, 28 NF1-only, 30 ADHD-only) performed the German version of the intelligence test WISC-IV and a continuous performance test (T.O.V.A.) to assess attention functions. Parents completed questionnaires about everyday attention and executive functions (Conners 3®, BRIEF). Results. Children with NF1 plus ADHD showed significantly lower intelligence test scores (full-scale IQ: 89.39 [1.40]) than patients with NF1-only (full-scale IQ: 101.14 [1.98]; ), and intellectual functioning correlated significantly with attention performance in NF1 ( ). As compared to NF1-only, attention, and executive functioning were impaired on several dimensions (T.O.V.A., Conners 3® and BRIEF) in NF1 plus ADHD. ADHD-only was associated with significantly higher problem scores regarding hyperactivity/impulsivity and inattention (Conners 3®). NF1-only was associated with inattentiveness when compared to the normative sample of the T.O.V.A. Conclusion. NF1 is associated with variable attention problems. Severe attention deficits appear to be a risk factor for intellectual dysfunction in NF1, more than NF1 without attention deficit. NF1 plus ADHD presents a specific cognitive profile, which differs from that of NF1 and from neurotypical ADHD

Motor dysfunction in NF1: Mediated by attention deficit or inherent to the disorder?

AIM Attention deficit and compromised motor skills are both prevalent in Neurofibromatosis type 1 (NF1), but the relationship is unclear. We investigated motor function in children with NF1 and in children with Attention Deficit/Hyperactivity Disorder (ADHD), and explored if, in patients with NF1, attention deficit influences motor performance. METHODS Motor performance was measured using the Movement Assessment Battery for Children (M-ABC) in 71 children (26 with NF1 plus ADHD, 14 with NF1 without ADHD, and 31 with ADHD without NF1) aged 6-12 years. RESULTS There was a significant effect of group on motor performance. Both NF1 groups scored below children with ADHD without NF1. Attention performance mediated motor performance in children with ADHD without NF1, but not in children with NF1. CONCLUSIONS Motor function is not mediated by attention performance in children with NF1. While in ADHD, attention deficit influences motor performance, motor problems in NF1 seem to be independent from attention deficit. This argues for different pathomechanisms in these two groups of developmental disorders