Pérez-Vigil A, et al. - Researchers examined the relationship of Tourette syndrome and chronic tic disorders with objectively measured educational outcomes, adjusting for measured covariates and unmeasured factors shared amongst siblings and accounting for common psychiatric comorbidities. They reported that treatment-seeking people with Tourette syndrome or chronic tic disorders seen in specialist settings experienced substantial academic underachievement across all educational levels, spanning from compulsory school to university, even after accounting for multiple confounding factors and psychiatric comorbidities.

Methods

• A population-based birth cohort comprising of all people born in Sweden from 1976 to 1998 was followed up until December 2013.
• People with organic brain disorders, mental retardation, and 2 foreign-born parents were excluded.
• Families with at least 2 singleton full siblings and families with siblings discordant for Tourette syndrome or chronic tic disorders were identified.
• Eligibility to access upper secondary school after compulsory education, finishing upper secondary school, starting a university degree, and finishing a university degree were the main outcomes measured.

Results

• As per data, of the 2,115,554 people in the cohort, 3,590 had a registered diagnosis of Tourette syndrome or a chronic tic disorder in specialist care (of whom 2,822 [78.6%] were male; median [interquartile] age at first diagnosis, 14.0 [11-18] years).
• It was noted that of 726,198 families with at least two singleton full siblings, 2,697 included siblings discordant for these disorders.
• Findings revealed that people with Tourette syndrome or chronic tic disorders were significantly less likely to pass all core and additional courses at the end of compulsory school (odds ratios ranging from 0.23 [95% CI, 0.20-0.26] for the handcraft textile/wood course to 0.36 [95% CI, 0.31-0.41] for the English language course) and to access a vocational program (adjusted OR [aOR], 0.31; 95% CI, 0.28-0.34) or academic program (aOR, 0.43; 95% CI, 0.39-0.47) in upper secondary education vs unexposed individuals.
• In addition, people with these disorders were less likely to finish upper secondary education (aOR, 0.35; 95% CI, 0.32-0.37), start a university degree (aOR, 0.41; 95% CI, 0.37-0.46), and finish a university degree (aOR, 0.39; 95% CI, 0.32-0.48).
• In the fully adjusted sibling comparison models, the results were only marginally weakened.
• Excluding patients with neuropsychiatric comorbidities, especially attention-deficit/hyperactivity disorder and pervasive developmental disorders, resulted in attenuated estimates, however, patients with Tourette syndrome or chronic tic disorders were still significantly impaired across all outcomes.