The prevalence of Gilles de la Tourette syndrome in children and adolescents with autism: a large scale study

Psychol Med. 1999 Sep;29(5):1151-9. doi: 10.1017/s003329179900896x.


Background: An earlier small-scale study of children with autism revealed that 8.1% of such patients were co-morbid for Gilles de la Tourette syndrome (GTS). The present study is a large scale test of whether this result replicates.

Method: Four hundred and forty-seven pupils from nine schools for children and adolescents with autism were screened for the presence of motor and vocal tics.

Results: Subsequent family interviews confirmed the co-morbid diagnosis of definite GTS in 19 children, giving a prevalence rate of 4.3%. A further 10 children were diagnosed with probable GTS (2.2%).

Conclusions: These results indicate that the rate of GTS in autism exceeds that expected by chance, and the combined rate (6.5%) is similar to the rates found in the smaller-scale study. Methodological considerations and alternative explanations for an increased prevalence are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Autistic Disorder / complications*
  • Autistic Disorder / psychology
  • Child
  • Child, Preschool
  • Comorbidity
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Prevalence
  • Tourette Syndrome / epidemiology*