title: Increasing exposure to antibody-stimulating proteins and polysaccharides in vaccines is not associated with risk of autism.
abstract: OBJECTIVE
  To evaluate the association between autism and the level of immunologic stimulation received from vaccines administered during the first 2 years of life.
  
  
  METHODS
  We analyzed data from a case-control study conducted in 3 managed care organizations (MCOs) of 256 children with autism spectrum disorder (ASD) and 752 control children matched on birth year, sex, and MCO. In addition to the broader category of ASD, we also evaluated autistic disorder and ASD with regression. ASD diagnoses were validated through standardized in-person evaluations. Exposure to total antibody-stimulating proteins and polysaccharides from vaccines was determined by summing the antigen content of each vaccine received, as obtained from immunization registries and medical records. Potential confounding factors were ascertained from parent interviews and medical charts. Conditional logistic regression was used to assess associations between ASD outcomes and exposure to antigens in selected time periods.
  
  
  RESULTS
  The aOR (95% CI) of ASD associated with each 25-unit increase in total antigen exposure was 0.999 (0.994-1.003) for cumulative exposure to age 3 months, 0.999 (0.997-1.001) for cumulative exposure to age 7 months, and 0.999 (0.998-1.001) for cumulative exposure to age 2 years. Similarly, no increased risk was found for autistic disorder or ASD with regression.
  
  
  CONCLUSIONS
  In this study of MCO members, increasing exposure to antibody-stimulating proteins and polysaccharides in vaccines during the first 2 years of life was not related to the risk of developing an ASD.
authors.affiliation: Immunization Safety Office, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. fxd1@cdc.gov
authors.forename: Frank
authors.initials: F
authors.lastname: DeStefano
authors.forename: Cristofer S
authors.initials: CS
authors.lastname: Price
authors.forename: Eric S
authors.initials: ES
authors.lastname: Weintraub
mesh_terms: D000906:Antibodies / Q000276:immunology*; D001321:Autistic Disorder / Q000209:etiology; D016022:Case-Control Studies; D002659:Child Development Disorders, Pervasive / Q000209:etiology*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011134:Polysaccharides / Q000009:adverse effects / Q000276:immunology*; D011506:Proteins / Q000009:adverse effects / Q000276:immunology*; D018570:Risk Assessment; D014612:Vaccines / Q000009:adverse effects / Q000276:immunology*
chemical_list: D000906:Antibodies; D011134:Polysaccharides; D011506:Proteins; D014612:Vaccines
keywords: AD; ADI-R; ADOS; ASD; Autism Diagnostic Interview–Revised; Autism Diagnostic Observation Schedule; Autism spectrum disorder; Autistic disorder; MCO; Managed care organization; SCQ; Social Communication Questionnaire