Disentangling the Overlap between Tourette's Disorder and ADHD

Abstract

These findings confirm previously noted associations between Tourette's syndrome and OCD but suggest that disruptive behavioral, mood, and anxiety disorders as well as cognitive dysfunctions may be accounted for by comorbidity with ADHD. However, Tourette's syndrome plus ADHD appears to be a more severe condition than ADHD alone.

Chronic tic disorders in children with ADHD

“…Consistent with a previous study, children with ADHD+TS and ADHD-only were comparable across all academic testing subscales 25. These findings are also supported by the extensive literature on children with tics, which suggests that tics are not significant predictors of academic problems 31…”

Clinical Characteristics of Children and Adolescents with a Primary Tic Disorder

“…The percentage of participants meeting DSM-IV diagnostic criteria for co-occurring ADHD was much lower than clinically-ascertained case series (Scahill et al 2009; Spencer et al 1998; Sukhodolsky et al 2003) but was still the most common co-occurring condition in this sample. ADHD was the most common concomitant condition in the 9–13-year-old participants, was more common in 9–13 year-olds than 14–17 year olds, and appeared to contribute to poorer global psychosocial functioning, poorer adaptive/social functioning, and perceived strain on family members when tic severity and other Axis I conditions were statistically controlled.…”

“…The emergence of social phobia as the prominent co-occurring condition in late adolescence likely reflects the later age of onset for this condition. The somewhat higher than expected rates of social phobia in comparison to prior reports (e.g., Spencer et al 1998) likely results from our use of the ADIS-RLV which, by design, provides a systematic assessment of anxiety disorders including social phobia.…”

The familial association of tourette's disorder and ADHD: The impact of OCD symptoms

“…This analysis also revealed an association between proband OCD/OCDsub diagnosis and increased rate of TD/ADHD comorbidity in the relatives, regardless of whether the proband had TD or ADHD or both. These results suggest that there may be a TD/OCD/ADHD familial subtype, which could represent a more severe form of TD (Spencer et al, 1998). …”

“…In a prospective study of children at risk for TD, children of two TD-affected parents had three times greater risk of developing ADHD compared to the children of one affected parent, and two times greater risk of developing either tics, ADHD, or OCD (McMahon et al, 2003). TD appearing in the context of ADHD is likely to represent a more severe form of TD than TD without ADHD (Spencer et al, 1998). Patients with comorbid TD and ADHD perform less on cognitive tasks than patients with TD alone (Brand et al, 2002; Ozonoff et al, 1998; Pennington and Ozonoff, 1996), have significantly increased rates of anger control problems (Budman et al, 2000; Freeman, 2007; Stephens and Sandor, 1999; Sukhodolsky et al, 2003) and tic severity (Mol Debes et al, 2008).…”