|Classification and external resources|
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). Tic disorders are defined similarly by the World Health Organization (ICD-10 codes).
|Video clips of tics|
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.
Tic disorders, in order of severity, are:
- 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
- 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
- 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
- The word stereotyped was removed from tic definition: stereotypies and stereotypic movement disorder are frequently misdiagnosed as tics or Tourette syndrome. 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.
- 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.
- 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.
- 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. The new categories account for tics with onset in adulthood, or tics triggered by other medical conditions or illicit drug use.
Treatment of tic disorders, although not usually necessary, is similar to treatment of Tourette syndrome.
Tic disorders are more common among males than females.
A large, community-based study suggested that over 19% of school-age children have tic disorders; 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. 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.
- American Psychiatric Association (2000). DSM-IV-TR: Tourette's Disorder. Diagnostic and Statistical Manual of Mental Disorders, 4th ed., text revision (DSM-IV-TR), ISBN 0-89042-025-4. Available at BehaveNet.com Retrieved on August 10, 2009.
- Swain JE, Scahill L, Lombroso PJ, King RA, Leckman JF. "Tourette syndrome and tic disorders: a decade of progress". J Am Acad Child Adolesc Psychiatry. 2007 Aug;46(8):947–68 doi:10.1097/chi.0b013e318068fbcc PMID 17667475
- American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders (Fifth ed.). Arlington, VA: American Psychiatric Publishing. pp. 81–85. ISBN 978-0-89042-555-8.
- ICD Version 2006. World Health Organization. Retrieved on 2007-05-24.
- Evidente VG. "Is it a tic or Tourette's? Clues for differentiating simple from more complex tic disorders". Postgraduate medicine108 (5): 175-6, 179-82. PMID 11043089 Retrieved on 2007-05-24
- Neurodevelopmental disorders. American Psychiatric Association. Retrieved on December 29, 2011.
- Moran, M. "DSM-5 provides new take on neurodevelopment disorders". Psychiatric News. January 18, 2013;48(2):6–23. doi:10.1176/appi.pn.2013.1b11
- "Highlights of changes from DSM-IV-TR to DSM-5" (PDF). American Psychiatric Association. 2013. Retrieved on June 5, 2013.
- Ellis CR, Pataki C. "Background: Childhood Habit Behaviors and Stereotypic Movement Disorder". Medscape. Retrieved October 6, 2013.
- Plessen KJ. Tic disorders and Tourette's syndrome. Eur Child Adolesc Psychiatry. 2013 Feb;22 Suppl 1:S55–60. PMID 23224240 doi:10.1007/s00787-012-0362-x
- Kurlan R, McDermott MP, Deeley C, et al. "Prevalence of tics in schoolchildren and association with placement in special education". Neurology 57 (8): 1383-8. PMID 11673576
- Tourette Syndrome Fact Sheet. National Institutes of Health (NIH). Retrieved on 2005-03-23.
- Swerdlow NR. "Tourette syndrome: current controversies and the battlefield landscape". Current neurology and neuroscience reports. 5 (5): 329-31. doi:10.1007/s11910-005-0054-8 PMID 16131414
- The Tourette Syndrome Classification Study Group. "Definitions and classification of tic disorders". Arch Neurol. 1993 Oct;50(10):1013-6. PMID 8215958. Retrieved on 2005-03-22
- Walkup JT, Ferrão Y, Leckman JF, Stein DJ, Singer H. Tic disorders: some key issues for DSM-V (PDF). Depress Anxiety. 2010 Jun;27(6):600–10. PMID 20533370 doi:10.1002/da.20711