title: Cognitive ability in Down syndrome and its relationship to urinary neopterin, a marker of activated cellular immunity.
abstract: Neopterin is an unconjugated pteridine that is secreted in large quantities by activated macrophages and can be used as a clinical marker of activated cellular immunity and oxidative stress. We aimed to investigate whether urinary neopterin levels are associated with cognitive function in people with Down syndrome (DS).
  
  
  
  Out of 32 adults with DS who originally participated in a longitudinal study, 25 were followed up at 4 years. Informants rated their adaptive behavior (ABAS) and the adults with DS attempted assessments of language skills and memory at both baseline and follow-up time points (Modified Memory Object Task, MOMT), and receptive vocabulary (British Picture Vocabulary Scale, BPVS).
  
  
  
  Neopterin/creatinine levels were negatively correlated with change in the MOMT total score (Spearman's Rho=-0.517, p=0.020) and change in the MOMT delayed recall score (Spearman's Rho=-0.577, p=0.008) over time, i.e. higher neopterin/creatinine level was associated with worse performance on a test of cognitive ability over time.
  
  
  
  Urine neopterin may have potential as a biomarker for memory decline in Down syndrome, and could potentially also help to track progression of mild cognitive impairment (MCI) to Alzheimer's disease in other high risk populations.
authors.affiliation: University College London, Division of Psychiatry, London, United Kingdom; Sheffield Teaching Hospitals NHS Trust, Department of Neurology, Sheffield, United Kingdom. Electronic address: takiszis@gmail.com.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Zis
authors.affiliation: University College London, Division of Psychiatry, London, United Kingdom; The LonDowns Consortium, United Kingdom.
authors.forename: André
authors.initials: A
authors.lastname: Strydom
authors.affiliation: Centre for Biomarker Research, School of Applied Sciences, University of Huddersfield, Huddersfield, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Buckley
authors.affiliation: Centre for Biomarker Research, School of Applied Sciences, University of Huddersfield, Huddersfield, United Kingdom.
authors.forename: Daniel
authors.initials: D
authors.lastname: Adekitan
authors.affiliation: Centre for Biomarker Research, School of Applied Sciences, University of Huddersfield, Huddersfield, United Kingdom.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: McHugh
mesh_terms: D000328:Adult; D000544:Alzheimer Disease; D003071:Cognition / Q000502:physiology*; D018450:Disease Progression; D004314:Down Syndrome / Q000150:complications / Q000503:physiopathology* / Q000652:urine; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000503:physiopathology / Q000652:urine; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D019798:Neopterin / Q000652:urine*
chemical_list: D019798:Neopterin
keywords: Aging; Alzheimer’s disease; Down syndrome; Memory; Neopterin; Oxidative stress