Lifetime prevalence, age of risk, and genetic relationships of comorbid psychiatric disorders in Tourette syndrome.

JAMA Psychiatry
Authors
Keywords
Abstract

IMPORTANCE: Tourette syndrome (TS) is characterized by high rates of psychiatric comorbidity; however, few studies have fully characterized these comorbidities. Furthermore, most studies have included relatively few participants (

OBJECTIVE: To characterize the lifetime prevalence, clinical associations, ages of highest risk, and etiology of psychiatric comorbidity among individuals with TS.

DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional structured diagnostic interviews conducted between April 1, 1992, and December 31, 2008, of participants with TS (n = 1374) and TS-unaffected family members (n = 1142).

MAIN OUTCOMES AND MEASURES: Lifetime prevalence of comorbid DSM-IV-TR disorders, their heritabilities, ages of maximal risk, and associations with symptom severity, age at onset, and parental psychiatric history.

RESULTS: The lifetime prevalence of any psychiatric comorbidity among individuals with TS was 85.7%; 57.7% of the population had 2 or more psychiatric disorders. The mean (SD) number of lifetime comorbid diagnoses was 2.1 (1.6); the mean number was 0.9 (1.3) when obsessive-compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD) were excluded, and 72.1% of the individuals met the criteria for OCD or ADHD. Other disorders, including mood, anxiety, and disruptive behavior, each occurred in approximately 30% of the participants. The age of greatest risk for the onset of most comorbid psychiatric disorders was between 4 and 10 years, with the exception of eating and substance use disorders, which began in adolescence (interquartile range, 15-19 years for both). Tourette syndrome was associated with increased risk of anxiety (odds ratio [OR], 1.4; 95% CI, 1.0-1.9; P = .04) and decreased risk of substance use disorders (OR, 0.6; 95% CI, 0.3-0.9; P = .02) independent from comorbid OCD and ADHD; however, high rates of mood disorders among participants with TS (29.8%) may be accounted for by comorbid OCD (OR, 3.7; 95% CI, 2.9-4.8; P 

CONCLUSIONS AND RELEVANCE: This study is, to our knowledge, the most comprehensive of its kind. It confirms the belief that psychiatric comorbidities are common among individuals with TS, demonstrates that most comorbidities begin early in life, and indicates that certain comorbidities may be mediated by the presence of comorbid OCD or ADHD. In addition, genetic analyses suggest that some comorbidities may be more biologically related to OCD and/or ADHD rather than to TS.

Year of Publication
2015
Journal
JAMA Psychiatry
Volume
72
Issue
4
Pages
325-33
Date Published
2015 Apr
ISSN
2168-6238
DOI
10.1001/jamapsychiatry.2014.2650
PubMed ID
25671412
PubMed Central ID
PMC4446055
Links
Grant list
K23 MH085057 / MH / NIMH NIH HHS / United States
R01 MH096767 / MH / NIMH NIH HHS / United States
R01 MH096767 / MH / NIMH NIH HHS / United States
U01 NS40024 / NS / NINDS NIH HHS / United States