Tic disorders

Tic disorder
Classification and external resources
ICD-10 9 DiseasesDB eMedicine MeSH D013981

Tic disorders are defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM) based on type (motor or phonic) and duration of tics (sudden, rapid, nonrhythmic movements).[1] Tic disorders are defined similarly by the World Health Organization (ICD-10 codes).[2]

Classification

The fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published in May 2013, classifies Tourette's and tic disorders as motor disorders listed in the neurodevelopmental disorder category.[3]

Tic disorders, in order of severity, are:[3]

  • 307.20 Other specified tic disorder (specify reason)
  • 307.20 Unspecified tic disorder
  • 307.21 Provisional tic disorder
  • 307.22 Persistent (chronic) motor or vocal tic disorder (specify motor or vocal)
  • 307.23 Tourette's disorder

ICD codes

ICD10 diagnosis codes are:[4]

  • F95.0 Transient tic disorder
  • F95.1 Chronic motor or vocal tic disorder
  • F95.2 Combined vocal and multiple motor tic disorder [de la Tourette]
  • F95.8 Other tic disorders
  • F95.9 Tic disorder, unspecified

DSM-IV-TR

In the fourth revision of the DSM (DSM-IV-TR), tic disorders were classified as follows:[5]

  • Transient tic disorder consisted of multiple motor and/or phonic tics with duration of at least 4 weeks, but less than 12 months.
  • Chronic tic disorder was either single or multiple motor or phonic tics, but not both, which were present for more than a year.
  • Tourette syndrome was diagnosed when both motor and phonic tics were present for more than a year.
  • Tic Disorder NOS was diagnosed when tics were present, but did not meet the criteria for any specific tic disorder.

From DSM-IV-TR to DSM-5

DSM-5 was published in 2013, updating DSM-IV-TR, which was published in 2000. The following changes were made:[3][6][7][8]

  • The word stereotyped was removed from tic definition: stereotypies and stereotypic movement disorder are frequently misdiagnosed as tics or Tourette syndrome.[9] The definition of tic was made consistent for all tic disorders, and the word stereotyped was removed to help distinguish between stereotypies (common in autism spectrum disorders) and tic disorders.[10]
  • Provisional tic disorder replaced transient tic disorder: because initially presenting tics may eventually be diagnosed as chronic tic disorder or Tourette's, transient can only be defined in retrospect and is not very useful to the clinician. The term provisional "satisfies experts with a more systematic epidemiological approach to disorders", but should not imply that treatment might not be called for.[10]
  • Differentiation of chronic motor or vocal tic disorder: DSM-5 added a specifier to distinguish between vocal and motor tics that are chronic. This distinction was added because higher rates of comordid diagnoses are present with vocal tics relative to motor tics.[10]
  • Stimulant use as a cause removed: there is no evidence that the use of stimulants causes tics.[10]
  • New categories, Other specified and Unspecified: for tic disorders that result in significant impairment to the individual yet do not meet the full criteria for other tic disorders.[3] The new categories account for tics with onset in adulthood,[3] or tics triggered by other medical conditions or illicit drug use.[10]

Diagnosis

Further information: Tic § Differential diagnosis

Tics should be distinguished from other causes of tourettism, stereotypies, chorea, dyskinesias, myoclonus, and obsessive-compulsive disorder.[3]

Treatment

Treatment of tic disorders, although not usually necessary, is similar to treatment of Tourette syndrome.

Epidemiology

Tic disorders are more common among males than females.[3]

A large, community-based study suggested that over 19% of school-age children have tic disorders;[11] the children with tic disorders in that study were usually undiagnosed.

As many as 1 in 100 people may experience some form of tic disorder, usually before the onset of puberty.[12] Tourette syndrome is the more severe expression of a spectrum of tic disorders, which are thought to be due to the same genetic vulnerability. Nevertheless, most cases of Tourette syndrome are not severe. Although a significant amount of investigative work indicates genetic linkage of the various tic disorders, further study is needed to confirm the relationship.[13]

References

Further reading

  • The Tourette Syndrome Classification Study Group. PMID 8215958. Retrieved on 2005-03-22
  • Walkup JT, Ferrão Y, Leckman JF, Stein DJ, Singer H. 10.1002/da.20711
ru:Нервный тик
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.