NOTE: This page is under construction. See www.tics-r.us for links to other, more complete sources. /kjb 28 Feb 2012

Tourette syndrome and tics

Definition and nosology

Tourette syndrome and chronic tic disorder are essentially the same

  1. Vocal tics are after all movements of the muscles of phonation and respiration
  2. Different tics come and go over time
  3. Family studies and phenotype studies suggest few differences between TS and CTD. Differences are mostly in the directly that TS is more associated with higher severity and with higher rates of OCD (e.g., Spencer et al 1995; Saccomani et al 2005; Grados and Matthews 2009). However, note that rating scales such as the total tic score of the YGTSS are constructed so that the addition of even one mild vocal tic raises the total severity score by several points, whereas adding another motor tic may not change the score.

People with tics often—perhaps usually—also have ADHD or OCD

Comings et al 1992 (but note the comments about persecutory symptoms have not panned out in subsequent studies)

Childhood-onset OCD is very often an indicator of a tic disorder

  1. Follow-up after 2 to 7 years of 54 children with OCD, excluded at baseline for Tourette syndrome, showed that most (59%) had tics at some time in life. Almost all (57%) had them at baseline. Leonard et al 1992

Etiology


Pathophysiology

Tics occur during all stages of sleep

"At all stages of sleep, body movements during sleep were more frequent in cases of GTS than those in normal controls." Hashimoto et al 1980