Josef Isung1, Kayoko Isomura1, Henrik Larsson2,3, Anna Sidorchuk1, Lorena Fernández de la Cruz1, David Mataix-Cols1. 1. Centre for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet, & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden. 2. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. 3. School of Medical Sciences, Örebro University, Örebro, Sweden.
Abstract
Importance: Severe forms of Tourette syndrome or chronic tic disorder (TS/CTD) may involve repeated head jerking. Isolated case reports have described a spectrum of severe neck disorders in individuals with TS/CTD. However, the nature and prevalence of cervical spine disorders in TS/CTD are unknown. Objective: To establish if TS/CTD are associated with an increased risk of cervical spine disorders and related neurological complications compared with individuals from the general population. Design, Setting, and Participants: All individuals born from 1973 to 2013 and living in Sweden between 1997 and 2013 were identified. Individuals with a record of TS/CTD diagnosed in specialist settings were matched on age, sex, and county of birth with 10 unexposed individuals randomly selected from the general population. Cox proportional hazards regression models were used to estimate the risk of vascular and nonvascular cervical spine disorders among exposed individuals, compared with unexposed individuals. Models were adjusted for other known causes of cervical spine injury. Data were analyzed from March 19 to May 16, 2021. Exposures: International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnoses of TS/CTD in the Swedish National Patient Register. Main Outcomes and Measures: Records of cervical vascular disorders (ie, aneurysm, cerebral infarction, transitory cerebral ischemia) and cervical nonvascular disorders (ie, spondylosis, cervical disc disorders, fractures of the cervical spine, cervicalgia) and cervical surgeries. Covariates included rheumatic disorders, traffic injuries, fall- or sport-related injuries, and attention-deficit/hyperactivity disorder comorbidity. Results: A total of 6791 individuals with TS/CTD were identified (5238 [77.1%] were male; median [interquartile] age at first diagnosis, 15.6 [11.4-23.7] years) and matched to 67 910 unexposed individuals. Exposed individuals had a 39% increased risk of any cervical spine disorder (adjusted hazard ratio, 1.39; 95% CI, 1.22-1.59). Adjusted hazard ratios for cervical vascular and nonvascular disorders were 1.57 (95% CI, 1.16-2.13) and 1.38 (95% CI, 1.19-1.60), respectively. Risks were similar among men and women. Conclusions and Relevance: Individuals with severe TS/CTD are at increased risk of cervical spine disorders. These outcomes are relatively rare but may lead to persistent disability in some individuals and thus require close monitoring to facilitate early interventions.
Importance: Severe forms of Tourette syndrome or chronic tic disorder (TS/CTD) may involve repeated head jerking. Isolated case reports have described a spectrum of severe neck disorders in individuals with TS/CTD. However, the nature and prevalence of cervical spine disorders in TS/CTD are unknown. Objective: To establish if TS/CTD are associated with an increased risk of cervical spine disorders and related neurological complications compared with individuals from the general population. Design, Setting, and Participants: All individuals born from 1973 to 2013 and living in Sweden between 1997 and 2013 were identified. Individuals with a record of TS/CTD diagnosed in specialist settings were matched on age, sex, and county of birth with 10 unexposed individuals randomly selected from the general population. Cox proportional hazards regression models were used to estimate the risk of vascular and nonvascular cervical spine disorders among exposed individuals, compared with unexposed individuals. Models were adjusted for other known causes of cervical spine injury. Data were analyzed from March 19 to May 16, 2021. Exposures: International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnoses of TS/CTD in the Swedish National Patient Register. Main Outcomes and Measures: Records of cervical vascular disorders (ie, aneurysm, cerebral infarction, transitory cerebral ischemia) and cervical nonvascular disorders (ie, spondylosis, cervical disc disorders, fractures of the cervical spine, cervicalgia) and cervical surgeries. Covariates included rheumatic disorders, traffic injuries, fall- or sport-related injuries, and attention-deficit/hyperactivity disorder comorbidity. Results: A total of 6791 individuals with TS/CTD were identified (5238 [77.1%] were male; median [interquartile] age at first diagnosis, 15.6 [11.4-23.7] years) and matched to 67 910 unexposed individuals. Exposed individuals had a 39% increased risk of any cervical spine disorder (adjusted hazard ratio, 1.39; 95% CI, 1.22-1.59). Adjusted hazard ratios for cervical vascular and nonvascular disorders were 1.57 (95% CI, 1.16-2.13) and 1.38 (95% CI, 1.19-1.60), respectively. Risks were similar among men and women. Conclusions and Relevance: Individuals with severe TS/CTD are at increased risk of cervical spine disorders. These outcomes are relatively rare but may lead to persistent disability in some individuals and thus require close monitoring to facilitate early interventions.