Abstract
Background and Objective Tourette Syndrome (TS) and Persistent Motor or Vocal Tic Disorders (PMVT) are more prevalent in males (vs. females). Females with TS may have a delay in diagnosis, and more complex tic features (vs. males). With respect to comorbidities, obsessive-compulsive disorder (OCD) is more prevalent in females; attention-deficit hyperactivity disorder (ADHD) is more prevalent in males. Less is known about sex differences in PMVT. This study analyzes sex differences in outcomes among individuals with TS and PMVT in the Tourette Association of America International Consortium for Genetics dataset (TAAICG).
Design/Methods Data from 2403 individuals (N=2109 TS; N=294 PMVT) from the TAAICG were analyzed to explore the relationship between sex and TS or PMVT outcomes: age at tic onset; age at diagnosis; time-to-diagnosis; tic severity; and comorbidity rates. Regression models were adjusted for age and family relationships to examine the impact of sex on outcomes.
Results Females with TS (25.5% of the sample) had a later age of symptom onset (6.5±2.8 vs. 6.0±2.7; p=0.001), later age at diagnosis (13.3±11.2 vs. 10.7±8.1; p=0.0001), and a longer time-to-diagnosis [3 (1,7) vs. 2 (1,5), p=0.01] than males. The total Yale-Global Tic Severity Scale (YGTSS) was lower in females with TS (28.4±9.1 vs. 30.7±8.7); p<0.0001); OCD was slightly more prevalent in females (55% vs. 48.7%; p=0.01) although OCD severity did not differ by sex; ADHD was more prevalent in males (55.7% vs 38.9%; p<0.001). Females with TS had 0.46 lower odds of being diagnosed with TS (p<0.00001). Females with PMVT (42.9% of the sample) had an earlier age of symptom onset (7.9±3.3 vs. 8.9±3.7; p=0.05). Motor or vocal tic severity (YGTSS) was not significantly different. OCD, but not ADHD, was more prevalent in females (OCD: 41.9% vs. 22.2%; p<0.001: ADHD:16.5% vs 21.0%; p=0.4).
Conclusion Females with TS are less likely to be formally diagnosed and have a later age of symptom onset, later age at diagnosis, longer time-to-diagnosis, higher prevalence of OCD, and lower prevalence of ADHD (vs. males). Females with PMVT have an earlier age of symptom onset, higher prevalence of OCD, but similar ADHD prevalence rates (vs. males). Females with TS and PMVT may be clinically different than males with TS. Future research is needed to understand differences longitudinally in TS and PMVT.
Competing Interest Statement
Financial Disclosures: Marisela E. Dy-Hollins has received research support from NIH grant K12NS098482. Lori B. Chibnik has no financial disclosures. Natasha A Tracey has no financial disclosures. Lisa Osiecki has no financial disclosures. Cathy L. Budman reports no disclosures relevant to the manuscript. Danielle C. Cath has no financial disclosures. She has been an unpaid member of the steering committee of the European Society for the Study of Tourette Syndrome (ESSTS), and is a member of the Dutch TS advisory board.. Marco A. Grados reports no disclosures relevant to the manuscript. Robert A. King reports no disclosures relevant to the manuscript. Gholson Lyon reports no disclosures relevant to the manuscript. Guy A. Rouleau reports no disclosures relevant to the manuscript. Paul Sandor reports no disclosures relevant to the manuscript. Harvey S. Singer receives royalties from the 3rd edition of book, Movement Disorders in Childhood, Elsevier. Nutan Sharma has received research support from NIH grants NIH P01 NS087997 and R21 NS118541. Dr. Sharma has received honoraria from John Wiley Publishing for serving as editor-in-chief for Brain and Behavior. Carol A. Mathews has received research support from NIH grants R01NS105746 and R01NS102371. She is an unpaid member of the International OCD Foundation Scientific and Clinical Advisory Board and the Family Foundation for OCD Research Advisory Board. Jeremiah Scharf has received research support from NIH grants R01NS102371 and R01NS105746. Dr. Scharf is also an unpaid member of the Tourette Association of America Scientific Advisory Board.
Funding Statement
This study was funded by K12NS098482, R01 NS102371, and R01 NS105746. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
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The institutional review board at the Massachusetts General Brigham System gave ethical approval for all aspects of this work.
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Data will be shared through collaborative arrangements with qualified investigators.