title: Low serum sphingolipids in children with attention deficit-hyperactivity disorder.
abstract: BACKGROUND
  Attention deficit-hyperactivity disorder (ADHD) is the most prevalent neuropsychiatric condition in childhood. ADHD is a multifactorial trait with a strong genetic component. One neurodevelopmental hypothesis is that ADHD is associated with a lag in brain maturation. Sphingolipids are essential for brain development and neuronal functioning, but their role in ADHD pathogenesis is unexplored. We hypothesized that serum sphingolipid levels distinguish ADHD patients from unaffected subjects.
  
  
  METHODS
  We characterized serum sphingolipid profiles of ADHD patients and two control groups: non-affected relatives and non-affected subjects without a family history of ADHD. Sphingolipids were measured by LC-MS/MS in 77 participants (28 ADHD patients, 28 related controls, and 21 unrelated controls). ADHD diagnosis was based on the Diagnostic and Statistical Manual of Mental Disorders (DSM IV-TR). Diagnostic criteria were assessed by two independent observers. Groups were compared by parametrical statistics.
  
  
  RESULTS
  Serum sphingomyelins C16:0, C18:0, C18:1, C24:1, ceramide C24:0, and deoxy-ceramide C24:1 were significantly decreased in ADHD patients at 20-30% relative reductions. In our sample, decreased serum sphingomyelin levels distinguished ADHD patients with 79% sensitivity and 78% specificity.
  
  
  CONCLUSIONS
  Our results showed lower levels of all major serum sphingomyelins in ADHD. These findings may reflect brain maturation and affect neuro-functional pathways characteristic for ADHD.
authors.affiliation: Department of Pediatrics, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University New York, NY, USA ; Department of Clinical Laboratories, School of Medicine, Pontificia Universidad Católica de Chile Santiago, Chile.
authors.forename: Marcela P
authors.initials: MP
authors.lastname: Henríquez-Henríquez
authors.affiliation: Department of Clinical Laboratories, School of Medicine, Pontificia Universidad Católica de Chile Santiago, Chile.
authors.forename: Sandra
authors.initials: S
authors.lastname: Solari
authors.affiliation: Department of Clinical Laboratories, School of Medicine, Pontificia Universidad Católica de Chile Santiago, Chile.
authors.forename: Teresa
authors.initials: T
authors.lastname: Quiroga
authors.affiliation: Department of Pathology and Cell Biology, Columbia University New York, NY, USA.
authors.forename: Benjamin I
authors.initials: BI
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University New York, NY, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Deckelbaum
authors.affiliation: Department of Pathology and Cell Biology, Columbia University New York, NY, USA.
authors.forename: Tilla S
authors.initials: TS
authors.lastname: Worgall
keywords: ADHD; biomarker; ceramides; endophenotype; sphingolipids; sphingomyelins