EBD Blog

Individuals with Tourette Syndrome and comorbid Learning Disabilities differ from those who have Tourette Syndrome alone in eight specific ways, according to research by Lawrence Burd and colleague that was published in 2005.

BMC Pediatr. 2005 Sep 1;5:34.

Tourette Syndrome and learning disabilities.

Burd L, Freeman RD, Klug MG, Kerbeshian J.

Department of Pediatrics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota, USA. laburd@medicine.nodak.edu

BACKGROUND: Tourette Syndrome (TS) is a neurodevelopmental disorder of childhood. Learning disabilities are frequently comorbid with TS. Using the largest sample of TS patients ever reported, we sought to identify differences between subjects with TS only and subjects with TS and a comorbid learning disability. METHODS: We used the Tourette Syndrome International Consortium database (TIC) to compare subjects with comorbid Tourette Syndrome and learning disabilities (TS + LD) to subjects who did not have a comorbid learning disability (TS-LD). The TIC database contained 5,500 subjects. We had usable data on 5,450 subjects. RESULTS: We found 1,235 subjects with TS + LD. Significant differences between the TS + LD group and the TS-LD group were found for gender (.001), age onset (.030), age first seen (.001), age at diagnosis (.001), prenatal problems (.001), sibling or other family member with tics (.024), two or more affected family members (.009), and severe tics (.046). We used logistic modeling to identify the optimal prediction model of group membership. This resulted in a five variable model with the epidemiologic performance characteristics of accuracy 65.2% (model correctly classified 4,406 of 5,450 subjects), sensitivity 66.1%, and specificity 62.2%. CONCLUSION: Subjects with TS have high prevalence rates of comorbid learning disabilities. We identified phenotype differences between the TS-LD group compared to TS + LD group. In the evaluation of subjects with TS, the presence of a learning disability should always be a consideration. ADHD may be an important comorbid condition in the diagnosis of LD or may also be a potential confounder. Further research on etiology, course and response to intervention for subjects with TS only and TS with learning disabilities is needed.

Link to PUBMED abstract.