title: Neonatal levels of inflammatory markers and later risk of schizophrenia.
abstract: BACKGROUND
  There is a long-standing interest in investigating the impact of early-life immune abnormalities on later onset of psychosis. The aim of this study was to assess inflammatory marker levels in neonatal dried blood spots and their association with later risk of schizophrenia.
  
  
  METHODS
  This nested case-control study included 995 cases and 980 control subjects. Cases were identified using the Danish Psychiatric Central Register. Control subjects of same age and sex were identified using the Danish Civil Registration System. Samples for the identified individuals were retrieved from the Danish Neonatal Screening Biobank. Concentrations of 17 inflammatory markers were measured in eluates from dried blood spots using a bead-based multiplex assay. Incidence rate ratios were calculated using conditional logistic regression. Principal component analysis was used to capture the overall variation in the inflammatory markers' concentrations.
  
  
  RESULTS
  No significant differences were found for any of the analyzed interleukins. We did not find any association with schizophrenia for any of the other examined inflammatory markers.
  
  
  CONCLUSIONS
  Our results suggest that persons who develop schizophrenia do not have higher or lower levels of the examined inflammatory markers at the time of birth. Our findings differ from the studies of maternal inflammatory changes during the antenatal period for which associations with schizophrenia have previously been demonstrated.
authors.affiliation: National Centre for Register-Based Research, iPSYCH, Aarhus University, Aarhus, Denmark; Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus University, Aarhus, Denmark. Electronic address: prn@ncrr.dk.
authors.forename: Philip Rising
authors.initials: PR
authors.lastname: Nielsen
authors.affiliation: National Centre for Register-Based Research, iPSYCH, Aarhus University, Aarhus, Denmark; Centre for Integrated Register-Based Research, iPSYCH, Aarhus University, Aarhus, Denmark; Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus University, Aarhus, Denmark.
authors.forename: Esben
authors.initials: E
authors.lastname: Agerbo
authors.affiliation: Centre for Neonatal Screening, Department of Clinical Biochemistry, Immunology and Genetics, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Kristin
authors.initials: K
authors.lastname: Skogstrand
authors.affiliation: Centre for Neonatal Screening, Department of Clinical Biochemistry, Immunology and Genetics, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: David Michael
authors.initials: DM
authors.lastname: Hougaard
authors.affiliation: Physiology and Behavior Laboratory, Swiss Federal Institute of Technology Zurich, Schwerzenbach, Switzerland.
authors.forename: Urs
authors.initials: U
authors.lastname: Meyer
authors.affiliation: National Centre for Register-Based Research, iPSYCH, Aarhus University, Aarhus, Denmark; Centre for Integrated Register-Based Research, iPSYCH, Aarhus University, Aarhus, Denmark; Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus University, Aarhus, Denmark.
authors.forename: Preben Bo
authors.initials: PB
authors.lastname: Mortensen
mesh_terms: D001774:Blood Chemical Analysis; D016022:Case-Control Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007378:Interleukins / Q000097:blood; D016015:Logistic Models; D008297:Male; D025341:Principal Component Analysis; D012042:Registries; D012306:Risk; D012559:Schizophrenia / Q000453:epidemiology* / Q000276:immunology*; D055815:Young Adult
chemical_list: D007378:Interleukins
keywords: Blood; Cytokines; Denmark; Epidemiology; Etiology; Schizophrenia