title: Paternal age at birth and high-functioning autistic-spectrum disorder in offspring.
abstract: BACKGROUND
  Previous studies have reported the association between advanced paternal age at birth and the risk of autistic-spectrum disorder in offspring, including offspring with intellectual disability.
  
  
  OBJECTIVE
  To test whether an association between advanced paternal age at birth is found in offspring with high-functioning autistic-spectrum disorder (i.e. offspring without intellectual disability).
  
  
  METHODS
  A case-control study was conducted in Japan. The participants consisted of individuals with full-scale IQ>or=70, with a DSM-IV autistic disorder or related diagnosis. Unrelated healthy volunteers were recruited as controls. Parental ages were divided into tertiles (i.e. three age classes). Odds ratios and 95% confidence intervals were estimated using logistic regression analyses, with an adjustment for age, gender and birth order.
  
  
  RESULTS
  Eighty-four individuals with autistic-spectrum disorder but without intellectual disability and 208 healthy controls were enrolled. Increased paternal, but not maternal, age was associated with an elevated risk of high-functioning autistic-spectrum disorder. A one-level advance in paternal age class corresponded to a 1.8-fold increase in risk, after adjustment for covariates.
  
  
  CONCLUSIONS
  Advanced paternal age is associated with an increased risk for high-functioning autistic-spectrum disorder.
authors.affiliation: Osaka Hamamatsu Joint Research Center for Child Mental Development (OHJRC-CMD), Hamamatsu University School of Medicine, Hamamatsu 431-3192, Japan.
authors.forename: Kenji J
authors.initials: KJ
authors.lastname: Tsuchiya
authors.forename: Kaori
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Taishi
authors.initials: T
authors.lastname: Miyachi
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Tsujii
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakamura
authors.forename: Shu
authors.initials: S
authors.lastname: Takagai
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawai
authors.forename: Atsuko
authors.initials: A
authors.lastname: Yagi
authors.forename: Kimie
authors.initials: K
authors.lastname: Iwaki
authors.forename: Shiro
authors.initials: S
authors.lastname: Suda
authors.forename: Genichi
authors.initials: G
authors.lastname: Sugihara
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Iwata
authors.forename: Hideo
authors.initials: H
authors.lastname: Matsuzaki
authors.forename: Yoshimoto
authors.initials: Y
authors.lastname: Sekine
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Suzuki
authors.forename: Toshirou
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Norio
authors.initials: N
authors.lastname: Mori
authors.forename: Nori
authors.initials: N
authors.lastname: Takei
mesh_terms: D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000209:etiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007360:Intelligence; D008297:Male; D008423:Maternal Age; D010331:Paternal Age; D010641:Phenotype; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult