A Controlled Family Study of Attention-Deficit/Hyperactivity Disorder and Tourette's Disorder

Harvard University, Cambridge, Massachusetts, United States
Journal of the American Academy of Child & Adolescent Psychiatry (Impact Factor: 7.26). 11/2006; 45(11):1354-62. DOI: 10.1097/01.chi.0000251211.36868.fe
Source: PubMed


Although attention-deficit/hyperactivity disorder (ADHD) is frequently comorbid with Tourette's disorder (TD), it is unclear whether they have a common genetic etiology. Familial relationships between DSM-IV ADHD and TD are studied in TD+ADHD, TD-only (TD-ADHD), ADHD-only (ADHD-TD), and control groups.
Case-control, direct-interview family study of 692 relatives of 75 TD+ADHD, 74 TD-only, 41 ADHD-only, and 49 control probands collected between 1999 and 2004. Age-corrected prevalence rates, odds ratios, and predictors of TD, ADHD, and OCD among relatives are estimated from blinded best-estimate diagnoses using survival Kaplan-Meier and generalized estimating equation regression analyses.
In relatives of the TD-only group, although ADHD exceeded control rates (p=.03), ADHD-TD (p=.51) rates were not increased. In the ADHD-only group, TD was increased (p=.004) but TD-ADHD rates were not increased (p=.18). Comorbid ADHD+TD diagnoses in relatives were elevated in all case groups (p<or=.03). TD in relatives predicted comorbid ADHD (p<.001), and ADHD in relatives predicted comorbid TD (p<.001). OCD in relatives predicted both ADHD (p=.002) and TD (p<.001) in relatives.
TD and ADHD are not alternate phenotypes of a single underlying genetic cause. There is an increased risk of comorbid ADHD and TD in affected families, possibly reflecting some overlapping neurobiology or pathophysiology.

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    • "Etiological studies have demonstrated a complex relationship between TS, OCD, and ADHD, both phenotypically and genetically (Davis et al., 2013; Gunther et al., 2012; Mathews and Grados, 2011; McGrath et al., 2014; O'Rourke et al., 2011; Stewart et al., 2006; Yu et al., 2015). Additionally, recent evidence suggests that TS, OCD, and ADHD are polygenic, meaning many genes contribute jointly to their symptom expression (Davis et al., 2013; Gratten et al., 2014). "
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    ABSTRACT: Collecting phenotypic data necessary for genetic analyses of neuropsychiatric disorders is time consuming and costly. Development of web-based phenotype assessments would greatly improve the efficiency and cost-effectiveness of genetic research. However, evaluating the reliability of this approach compared to standard, in-depth clinical interviews is essential. The current study replicates and extends a preliminary report on the utility of a web-based screen for Tourette Syndrome (TS) and common comorbid diagnoses (obsessive compulsive disorder (OCD) and attention deficit/hyperactivity disorder (ADHD)). A subset of individuals who completed a web-based phenotyping assessment for a TS genetic study was invited to participate in semi-structured diagnostic clinical interviews. The data from these interviews were used to determine participants׳ diagnostic status for TS, OCD, and ADHD using best estimate procedures, which then served as the gold standard to compare diagnoses assigned using web-based screen data. The results show high rates of agreement for TS. Kappas for OCD and ADHD diagnoses were also high and together demonstrate the utility of this self-report data in comparison previous diagnoses from clinicians and dimensional assessment methods. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    Psychiatry Research 05/2015; 228(3). DOI:10.1016/j.psychres.2015.05.017 · 2.47 Impact Factor
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    • "The most frequent conditions are attention deficit disorders (ADHDs) in about 20% of the children, followed by obsessive compulsive disorder (OCD), self-injurious behavior, anxiety, depression, personality disorders, oppositional defiant disorder, and conduct disorders.7 ADHDs generally occur before tic onset and tend to decrease in 20% of children during adolescence, yet later than tics.8 OCD symptoms associated with tic disorders usually begin at a somewhat later age than tics (i.e., at around 10 years of age), and tend to remit in only about 40% of patients.9 Persistence of ADHD and OCD is associated with poorer psychosocial functioning.10 "
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    ABSTRACT: Tic disorders are neurodevelopmental disorders of childhood associated with psychiatric comorbidity and academic problems. Estimating the prevalence and understanding the epidemiology of tic disorders is more complex than was once thought. Until fairly recently, tic disorders were thought to be rare, but today tics are believed to be the most common movement disorder, with 0.2-46.3% of schoolchildren experiencing tics during their lifetime. Tentative explanations for differing prevalence estimates include the multidimensional nature of tics with a varied and heterogeneous presentation, and the use of different epidemiological methods and study designs. Literature review and analysis of methodological issues pertinent to epidemiological studies of tic disorders. Epidemiological studies of tic disorders were reviewed, and the main elements of epidemiological studies, including sample selection, case ascertainment strategy, definition of tic disorders, and the degree of coverage of the eligible population (i.e., the response rate) were examined. In order to improve the quality of epidemiological studies of tic disorders, a number of recommendations were made, including but not limited to a review of the diagnostic criteria for tic disorders, and inclusion of new tic disorder categories for those with tics of secondary etiology.
    05/2012; 2.
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    • "This could be an effect of differences in data acquisition , sample size, age of participants, recruitment sources, and inclusion/exclusion criteria in the considered studies. As already noted, both OCD and ADHD are highly comorbid with TS, a tic disorder with a prevalence of 0.5–1% (Gaze et al., 2006; Stewart et al., 2009). Patients with the attentive subtype of ADHD (also called ADD) frequently develop compulsive coping styles. "
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    ABSTRACT: Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder affecting approximately 1-3% of the population. OCD is probably an etiologically heterogeneous condition. Individuals with OCD frequently have additional psychiatric disorders concomitantly or at some time during their lifetime. Recently, some authors proposed an OCD sub-classification based on comorbidity. An important issue in assessing comorbidity is the fact that the non-response to treatment often involves the presence of comorbid conditions. Non-responsive patients are more likely to meet criteria for comorbid axis I or axis II disorders and the presence of a specific comorbid condition could be a distinguishing feature in OCD, with influence on the treatment adequacy and outcome.
    Frontiers in Psychiatry 12/2011; 2:70. DOI:10.3389/fpsyt.2011.00070
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