Background: Reports on cognitive outcomes in long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD) are scarce. We present results from neuropsychological assessments of eight patients diagnosed with LCHADD prior to newborn screening with regard to clinical disease severity.
Methods: Intellectual ability and adaptive and executive functions were assessed using age-appropriate Wechsler Scales, Adaptive Behavior Assessment Scales (ABAS), and Behavior Rating Inventory of Executive Function (BRIEF).
Results: Five patients performed in the normal range on IQ tests but with lower scores on verbal working memory. In addition, they had lower parent-rated adaptive and executive functions.Three patients had intellectual disabilities with IQs below normal and/or autism spectrum disorders. In addition, they had low results on parent-rated adaptive functions. (Two of these patients had epilepsy.) Conclusions: Patients with LCHADD seem to have a specific cognitive pattern, with presentation as intellectual disability and specific autistic deficiencies or a normal IQ with weaknesses in auditive verbal memory and adaptive and executive functions. Future studies are warranted to investigate whether newborn screening programs and early treatment may promote improved neuropsychological development and outcomes.
Keywords: Beta-oxidation disorder; Children; Cognitive outcome; Cognitive profile; Fatty acid oxidation disorder; Inborn error of metabolism; LCHAD; Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency; Neuropsychological development.