Long-Term Follow-up of Patients with Tourette Syndrome Larry Burd, PhD; Jacob Kerbeshain,MD; Amy Barth, BS; Marilyn G. Klug, PhD; Karilyn Avery, MD; Becky Benz, MD Department of Pediatric, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND

Abstract The goal of this study was to collect prospective longitudinal information on the development of an epidemiologically defined cohort of patients with Tourette syndrome (J Child Neurol 2001; 16: ).

Cohort established DSM – III criteria Statewide Study

Childhood Prevalence 5.2 per 10,000 Mean age 10.1 years

Results Thirty-nine of the 54 (72%) patients were located and interviewed. This sample was comprised of 30 males (77%) and nine females (23%). At the time of our initial evaluation or entry into the study cohort (between 1984 and 1985), the mean age was 122 months (10.1 years), with a minimum age of 35 months and a maximum age of 215 months. The mean age at the follow-up evaluation was 274 months (22.8 years); the youngest was 168 months, and the oldest was 336 months. This was a 507 person- years of follow-up, with a mean follow-up period of 13 years. The results are in the tables.

Mean age at follow up 22.8 years

Temporal Data on Tic Morphology from 39 Patients with Tourette Syndrome from North Dakota at Follow-up (Mean Age 22.8 Years) ___________________________________________________________________ Age When Tics PeakedMean SDRange (in months) Total (N = 35) Male (n = 27) Female (n = 8) – 180 ____________________________________________________________________

_______________________________________________ TotalMalesFemales Time of Peak TicsN(%)n(%)n(%) _______________________________________________________________________ Morning2(5)1(3)1(11) Noon1(3)0-1(11) Afternoon6(15)5(17)1(11) Stress6(15)6(20)0- Other6(15)5(17)1(11) Unknown18(46)13(43)5(56)

Most Common Comorbid Diagnosis at Initial Evaluation (Mean Age 10.1 Years) and Follow- up (Mean Age 22.8 Years) in 39 Patients with Tourette Syndrome from North Dakota. ___________________________________________________________________________ Initial EvaluationFollow-up Diagnosisn(%)n(%) ___________________________________________________________________________ Tourette syndrome39(100)18(46) ADHD8(21)11(28) Depression4(10)3(8) Seizures6(15)1(3) Learning Disabilities5(13)4(10) Depression4(10)3(8) Bipolar disorder3(8)1(3) Obsessive-compulsive2(5)3(8) disorder

Syndromal Severity Tic Severity (Global Severity Rating Scale), Comorbidity (Number of Comorbid Neuropsychiatric Conditions Identified), and Reversed Global Assesment of Functioning Scores at Initial Evaluation

Initial Evaluation Follow-up Mean MeanChange (%) ____________________________________________________________ Global Severity Rating Scale (GSR) Total (59) Male (53) Female (82) ____________________________________________________________

Initial Evaluation Follow-up Mean MeanChange (%) _____________________________________________________________ Comorbity Total (42) Male (42) Female (32) _____________________________________________________________

Initial Evaluation Follow-up Mean MeanChange (%) ___________________________________________________ Reversed Global Assessment of Function (GAF) Total (50) Male (49) Female (53) ______________________________________________________________________________

Differences in Mean Tic Severity (Global Severity Rating Scale), Number of Comorbidities, Reversed Global Assessment of Functioning Score, and Composite Score at Initial Evaluation (Mean Age 10.1 Years) and at Follow-up (Mean Age 22.8 Years) in 39 Patients with Tourette Syndrome from North Dakota. _________________________________________________________________________________ MeasureMeanSDRange _________________________________________________________________________________ GSR at intake GSR at follow-up Comorbity at intake Comorbity at follow-up Reversed GAF at intake – 75 Reversed GAF at follow-up Composite Score at intake Composite Score at follow-up

__________________________________________________________ Results of Paired t-tests (Measure)Mean SD T Prob>/T/ ________________________________________________________ Differences in GSR Scores < Differences in comorbity < Differences in Reversed < GAF Scores Difference in composite < scores ___________________ The composite score is a linear combination of the three severity measures.

Longitudinal Course for Subjects with Tourette Syndrome High Severity Low 5% 15% 80%

Course of Tourette Syndrome 4 % improvement per year

Conclusions Tourette Syndrome is a common developmental disorder with a definable course. Based on this information close monitoring of pharmacological and other interventions is warranted. Long term treatment is likely necessary for only a minority of affected people. Strategies for management of episodic problems in TS are needed. This would be especially important for children six to thirteen years of age.