Tourette syndrome in youth with and without obsessive compulsive disorder and attention deficit hyperactivity disorder

Chronic tic disorders (TD) are consistently found to have high rates of comorbidity with obsessive-compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD). The purpose of this study is to compare the severity of TD only to TD with comorbid OCD or ADHD based on severity of tics, measures of psychopathology and additional comorbid diagnoses. Baseline data from 158 youth with a chronic TD who participated in two longitudinal studies were examined. Fifty-three percent (N = 85) of the youth also met criteria for a diagnosis of OCD, 38.6 % (n = 61) met criteria for ADHD and 24.1 % (N = 38) met criteria for both. Measures of interest addressed severity of tics, symptoms of anxiety, depression, ADHD, psychosocial stress, global functioning and the presence of comorbid diagnoses. Youth with comorbid TD and OCD were characterized by more severe tics, increased levels of depressive and anxious symptoms, heightened psychosocial stress and poorer global functioning. Youth with comorbid TD and ADHD did not differ from those with TD alone on measures of tic severity, but experienced greater psychosocial stress and poorer global functioning. Subjects with comorbid TD and OCD had more internalizing disorders than those without OCD, while those with comorbid ADHD were more likely to meet criteria for oppositional defiant disorder. TD with OCD is a more severe subtype of TD than TD without OCD. TD with ADHD is associated with higher psychosocial stress and more externalizing behaviors. Further research is needed into the underlying relationships between these closely associated conditions.     

Comorbidity of obsessive-compulsive disorder and attention-deficit/hyperactivity disorder in referred children and adolescents

OBJECTIVE: The aim of this study was to explore whether comorbid attention-deficit/hyperactivity disorder (ADHD) affects the clinical expression and outcome of obsessive-compulsive disorder (OCD) in a clinical sample. METHOD: A consecutive series of 94 children and adolescents (mean age, 13.6 +/- 2.8 years) with current diagnosis of OCD were included in the study. Twenty-four (25.5%) patients were diagnosed as having a comorbid ADHD. Subjects with OCD plus ADHD were compared with subjects with OCD but without ADHD. RESULTS: Comorbid ADHD with OCD was significantly associated with a higher rate of males, an earlier onset of OCD, a greater psychosocial impairment, and a heavier comorbidity, namely, with bipolar disorder, tic disorder, and oppositional defiant disorder/conduct disorder. Phenomenology of obsessions and compulsions and outcome were not affected by ADHD comorbidity. CONCLUSIONS: A screening for ADHD should be performed in patients with OCD, as these patients and their parents are frequently not aware that the impairment may be partly due to a comorbid ADHD.     

Comorbid behavioural problems in Tourette's syndrome are positively correlated with the severity of tic symptoms

OBJECTIVE: We studied the comorbid behavioural and mood problems in children with non-psychiatric Tourette's syndrome (TS) and their relationship with severity of tic disorder. METHOD: Sixty-nine TS children and 69 healthy controls were assessed by Child Behavior Checklist (CBCL) and Yale Global Tic Severity Scale (YGTSS). The relationships between behavioural problems and severity of tic symptoms were analysed statistically by comparison, correlation and multiple linear regression. RESULTS: Tourette's syndrome patients scored significantly lower (p<0.01) on the CBCL competency subscales and total score, and higher on all behavioural problem subscales and total score (p<0.01). Expectedly, the TS children had lower social competence than normal children. Among the TS children, the severity of tic symptoms is positively correlated with the severity of overall impairment in school and social competence. When the behavioural and mood problems commonly associated with TS were studied in detail, we found that delinquent behaviour, thought problems, attention problems, aggressive behaviour and externalizing are positively correlated with severity of tic symptoms. CONCLUSION: The findings indicated that children with TS-only also had a broad range of behavioural problems, and some of these were related to the severity of tic symptoms.     

Clinical correlates of quality of life in Tourette syndrome

Tourette syndrome (TS) is a neurodevelopmental disorder involving tics, which is frequently accompanied by comorbid obsessive compulsive (OCD) or attention deficit hyperactivity disorder (ADHD). Individuals with TS often report poor quality of life (QoL) in comparison with the general population. This study investigated the clinical correlates of QoL in young people with TS using a self‐report multidimensional QoL measure, and a range of clinical scales used to assess tic severity and the symptoms of anxiety, depression, OCD, ADHD and other emotional and behavioral symptoms. Symptoms of depression, OCD, and ADHD appeared to have a widespread negative impact on QoL, but poorer QoL was not associated with increased tic severity. Greater emotional and behavioral difficulties, including symptoms of OCD, were among the best predictors of poor QoL in young people with TS. © 2010 Movement Disorder Society     

The prognosis of Tourette syndrome: implications for clinical practice

Tourette syndrome (TS) is a childhood-onset neuropsychiatric condition characterised by multiple motor and phonic tics. Comorbid behavioural problems are common, especially attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). Little is known about the long-term prognosis of TS, despite the need to inform patients about their possible clinical course and advise health care providers on clinical resource allocation strategies. This paper reviews the scientific literature on the prognosis of TS spanning the period 1990-2010. After searching three scientific databases, we identified seven original studies investigating the prognosis of TS. It is suggested that tic frequency and severity decline with age in a large proportion of patients (59-85%). Predictors of increased tic severity in adulthood include higher childhood tic severity, smaller caudate volumes and poorer fine motor control. Furthermore, the presence of untreated comorbid psychopathology, such as ADHD and OCD, can adversely affect the long-term outcome of patients with TS. Future studies on the prognosis of TS should be conducted on larger samples, both in community and clinical settings.     

Sleep disorders in Tourette syndrome: a primary or unrelated problem?

Sleep disturbances are a common complaint in children with either Tourette syndrome (TS) or attention-deficit hyperactivity disorder (ADHD). Because a significant number of individuals with TS also have ADHD, we attempted to determine whether sleep difficulties reported in TS are a primary problem or are related to the co-occurrence of ADHD. Using a parent-completed sleep questionnaire, data were collected on boys, ages 7-14 years. Three groups, TS-only (N = 57), ADHD-only (N = 21), and TS+ADHD (N = 89), were compared to an age-matched control population (N = 146). The complaint of "poor sleep" occurred in 26% with TS-only, 48% with ADHD-only, and 41% with TS+ADHD; all were significantly different from 10% found in controls. Of 19 sleep questionnaire items, the incidence of problems occurred statistically more frequently in 5 of 19 for the TS-only group, in 6 of 19 for the ADHD-only group, and in 17 of 19 for the TS+ADHD group. Boys with TS+ADHD had many sleep problems which appeared to be related to an arousal disorder. Although the use of medications, especially stimulants and anti-depressants, were different between the TS-only and TS+ADHD groups, this factor did not account for the large discrepancies in sleep disturbance. In boys with TS, sleep problems usually occurred with the co-morbid feature ADHD.     

Disentangling the effects of Tourette syndrome and attention deficit hyperactivity disorder on cognitive and behavioral phenotypes

Eighty participants (62 males; 18 females; age range: 6-16 years) took part in the study, comprising four groups of 20 subjects each: TS-only, ADHD-only, TS+ADHD, controls. The age distributions, did not differ significantly among the four groups. The severity of symptoms, assessed by the TSGS, did not differ significantly between the two TS groups. Standardised measures were used throughout. The "cases" (i.e. TS-only, TS+ADHD, ADHD-only) were significantly different from controls on most measures of behavior. There were also differences amongst the various clinical subgroups, with, in general, TS-only participants being similar to controls with regards to both "total behavior" ratings and cognitive testing results. A diagnosis of ADHD, either or its own or in association with TS, was associated with greater maladaptive behavior and worse cognitive functioning. With regards to affective symptoms and anxiety, the three clinical groups did not differ from each other, but each of them was more affected than the control group. One finding in our study which differed from previous literature was that TS-only patients were rated as more "delinquent" than controls by their parents: possible reasons for this are discussed. Oppositional defiant disorder (ODD) was seen in a few (2,3,3 ODD patients in each clinical group), but as numbers were small no statistics were undertaken. Family histories were in accord with both TS and ADHD being genetic disorders, but sharing an overlap in only some cases. The "additive effect" hypothesis is discussed in detail in the light of our results and recent literature.     

Compulsive phenomena in children with tic disorder and attention deficit-hyperactive disorder

Tic disorders (TD), obsessive-compulsive disorders (OCD) and attention-deficit/hyperactivity disorder (ADHD) are often associated with deficits of impulse control and aggressive behavior. Tic disorders and OCD are closely related on epidemiological, psychopathological and neurobiological levels, whereas ADHD and OCD phenomena seem to be at opposite poles. Research evidence on the clinical significance of associated obsessive-compulsive behavior is reviewed and linked to our own new data. Thus the analyses of a worldwide database on Tourette's Syndrome (TS) (N = 4,833) showed that that the associated symptomatology of the OCD spectrum has to emphasized. In further investigations, premonitory sensorimotor phenomena reminiscent of OCD were more frequent in children with tic disorders as they grew older. Obsessive-compulsive behavior concomitant with TS was particularly associated with impulsive and aggressive behavior, as well as with depression and anxiety. The data suggest a reduced serotonergic transmission. Self-reports by children with ADHD, as opposed to those by their parents, mentioned a significantly higher quantitative degree of OC phenomena than those by children with TS. These findings suggest that OC symptoms in children with ADHD have so far been neglected in assessments by others. In summary, a complex psychopathological pattern of tic, OC behavior, impulsivity and internalizing symptomatology emerges that requires discriminating assessment and treatment.     

A transgenic model of comorbid Tourette's syndrome and obsessive-compulsive disorder circuitry

The tic disorder Tourette's Syndrome (TS) and obsessive-compulsive disorder (OCD) are comorbid behavioral disorders, suggesting a shared but still unknown neuronal basis. To 'circuit-test' such behaviors, we previously engineered transgenic mice expressing a neuropotentiating protein (cholera toxin A1 subunit) within a cortical-limbic subset of dopamine D1-receptor expressing (D1+) neurons known to trigger glutamatergic excitation of orbitofrontal, sensorimotor, limbic and efferent striatal circuits thought to be hyperactive or affected in OCD and TS. These mice exhibited OCD-like behaviors including generalized behavioral perseveration and compulsion-like leaping and grooming-associated pulling and biting of skin and hair. We now report that these OCD-like mice, like humans, also exhibit comorbid TS-like behaviors, including juvenile-onset tics; increased tic number, complexity and flurries; increased tic severity in males; voluntary tic suppression; and tic responsiveness to a non-cataleptic TS+OCD drug therapy (clonidine, 0.01 mg kg(-1)). These data suggest that hormonal gender differences, apart from the influence of genetic or autoimmune etiologic factors, may be sufficient to aggravate tic severity in human TS males compared to TS females. These data also proffer a precise neuronal basis for TS+OCD, wherein tics and primary compulsions or obsessions are evoked by hyperactivity of various cortical-limbic projection neurons' glutamatergic output to efferent targets like the striatum. The 'Cortical-limbic Glutamatergic Neuron' (CGN) neuronal circuit model merges formerly opposed neurotransmitter models of TS and OCD, and is consistent with new clinical reports of increased cortical hyperactivity, striatal glutamate and striatal inhibitory D2 receptors, and reduced striatal responsiveness, in these disorders.     

Locus of control,perceived parenting style,and symptoms of anxiety and depression in children with Tourette’s syndrome

AIM: This study explored the contribution of two psychosocial factors, locus of control (LOC) and perceived parenting style, to symptoms of internalizing disorders in children with Tourette syndrome (TS). This contribution was further evaluated in relation to TS severity. METHODS: Sixty-five children (53 boys, 12 girls) ages 9.0-16.9 years, of normal intelligence, completed questionnaires evaluating their depression and anxiety symptoms, LOC, and maternal parenting style. Their mothers rated TS severity, determined by tic severity, symptoms of attention-deficit hypreactivity disorder (ADHD) and obsessive compulsive symptoms (OCS). RESULTS: Higher rates of symptoms of anxiety and depression were associated with a more external LOC and a more rejecting and controlling parenting style. Additionally, depression correlated significantly with tic severity, ADHD and OCS, whereas anxiety correlated only with ADHD symptoms and OCS, but not with tics. Regression analyses showed that LOC, OCS and ADHD symptoms each significantly contributed to predicting anxiety level, whereas LOC and ADHD symptoms significantly contributed to predicting depression symptoms. CONCLUSIONS: Rates of symptoms of anxiety and depression in children with TS are markedly influenced by psychosocial factors, extending beyond the influence of ADHD and OCD, both common comorbid disorders in TS. An internal LOC, which is associated with an accepting and autonomy-granting parenting style, appears to be a protective factor against anxiety and depression.     

Antineuronal antibody status and phenotype analysis in Tourette's syndrome.

The Gilles de la Tourette syndrome (GTS) spectrum includes psychiatric comorbidities, mainly obsessive-compulsive disorder (OCD) and attention-deficit-hyperactivity disorder (ADHD). The role of environmental factors, e.g., antineuronal antibodies (ANeA), remains unclear. We compared the clinical features of ANeA-positive and ANeA-negative patients in 53 children and 75 adults with GTS. All diagnoses were made according to DSM-IV-TR criteria. A positive ANeA Western immunoblot showed bands for at least 1 of 3 reported striatal antigens (40, 45, and 60 kDa). Twelve children (23%) and 18 adults (25%) with GTS were ANeA-positive. Disease duration, tic phenomenology and severity, frequency of echo/pali/coprophenomena, self-injurious and aggressive behavior, or frequency of OCD comorbidity did not significantly differ between ANeA-positive and negative patients. Similar findings were obtained analyzing separately the three different antibody reactivities. A comorbid diagnosis of ADHD was significantly less frequent in GTS patients positive for the anti-60 kDa antibody only. Using a multivariate logistic regression model, adjusting for age, gender, and age at disease onset, a comorbid diagnosis of ADHD remained inversely associated with anti-60 kDa antibodies (odds ratio = 0.14; P = 0.002; 95% confidence interval 0.04-0.49). ANeA status does not differentiate a specific phenotype of GTS.     

Attentional functions in children and adolescents with attention-deficit/hyperactivity disorder with and without comorbid tic disorder

Summary Although the coexistence of attention-deficit/hyperactivity disorder (ADHD) and tic disorder (TD) is common, the nature of association is yet not fully understood. Thus, the aim of the present study was to explore attentional dysfunction in children with pure ADHD compared to children with comorbid ADHD + TD. Three groups of 20 children each, aged 8–15 years with either ADHD, ADHD + chronic tic disorder or Tourette syndrome (ADHD + TD) and a healthy control group were compared in their performance on three computerized attention tasks. Tasks of sustained attention, selective attention and interference control were employed. In addition, parental ratings of ADHD symptom severity and behaviour problems were obtained. Both clinical groups were rated as equally inattentive, however, externalising symptoms were more severe in the ADHD group. Objective measures of attentional performance revealed differences between the groups: whereas the ADHD group was markedly impaired in sustaining attention and selective attention/inhibitory control, the ADHD + TD group only showed marginal deficits in selective attention/inhibitory control. Possible explanations for the superior performance of the comorbid group are discussed: In particular, the results may indicate that in some patients, the tic disorder produces behavioural symptoms of ADHD, but not the broad neurocognitive deficits that usually are associated with ADHD. Alternatively, compensatory neural mechanisms of TD patients may result in a better neuropsychological performance of comorbid patients relative to patients suffering from pure ADHD. Correspondence: Ellen Greimel, Child Neuropsychology Section, Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital Aachen, 52074 Aachen, Germany     

Clinical course of Tourette syndrome

Objective

Tourette syndrome (TS) is a childhood-onset neuropsychiatric disorder characterized by multiple motor and vocal tics lasting at least a year in duration. Children with TS often experience comorbid conditions such as obsessive-compulsive disorder (OCD) and attention-deficit disorder. The goal of this article was to review the long-term clinical course of tics and comorbid conditions in children with TS.

Method

We conducted a traditional literature search to locate relevant articles regarding long-term outcome and prognosis in TS and tic disorders.

Results

Tics typically have an onset between the ages of 4 and 6 years and reach their worst-ever severity between the ages of 10 and 12 years. On average, tic severity declines during adolescence. By early adulthood, roughly three-quarters of children with TS will have greatly diminished tic symptoms and over one-third will be tic free. Comorbid conditions, such as OCD and other anxiety and depressive disorders, are more common during the adolescence and early adulthood of individuals with TS than in the general population.

Conclusion

Although tics are the sine qua non of TS, they are often not the most enduring or impairing symptoms in children with TS. Measures used to enhance self-esteem, such as encouraging strong friendships and the exploration of interests, are crucial to ensuring positive adulthood outcome in TS.     

Attention-deficit/hyperactivity disorder in children and adolescents with obsessive-compulsive disorder: fact or artifact?

OBJECTIVE: To clarify whether the symptoms of inattention and distractibility commonly seen in children and adolescents with obsessive-compulsive disorder (OCD) represent true comorbidity with attention-deficit/hyperactivity disorder (ADHD) or a manifestation of obsessional anxiety. METHOD: Phenotypic features and functional correlates of ADHD-like symptoms were examined in youths with and without OCD from a large sample of pediatric psychiatry patients consecutively referred since 1997. RESULTS: The number, frequency, and types of core ADHD symptoms as well as ADHD-associated functional indices were identical in all youths with DSM-IV-diagnosed ADHD irrespective of the presence or absence of comorbid OCD. CONCLUSION: These findings suggest that when ADHD-like symptoms are seen in youths with OCD, they reflect a true comorbid state of OCD plus ADHD and that the ADHD syndrome may be independent of OCD in comorbid youths.     

Neuropsychiatric disorders associated with streptococcal infection: a case-control study among privately insured children

ObjectiveTo assess whether antecedent streptococcal infection(s) increase the risk of subsequent diagnosis of obsessive-compulsive disorder (OCD), Tourette syndrome (TS), other tic disorders, attention-deficit/hyperactivity disorder (ADHD), or major depressive disorder (MDD) in a national sample of privately insured children.MethodUsing health insurance claims data, we compared the prior year's occurrence of streptococcal infection in children ages 4 to 13 years with OCD, TS, or tic disorder newly diagnosed between January 1998 and December 2004 to that of a cohort of matched controls. Conditional logistic regression models were used to determine the association of prior streptococcal sore throat or scarlet fever with a diagnosis of OCD, TS, or tic disorder. We repeated the analyses for two other infectious diseases (otitis media and sinusitis) and one noninfectious condition (migraine). We also investigated the potential specificity of this association by performing similar analyses focused on newly diagnosed ADHD and newly diagnosed MDD.ResultsSubjects with newly diagnosed OCD, TS, or tic disorder were more likely than controls to have had a diagnosis of streptococcal infection in the previous year (odds ratio 1.54,95% confidence interval 1.29–2.15). Prior streptococcal infection was also associated with incident diagnoses of ADHD (odds ratio 1.20, 95% confidence interval 1.06–1.35) and MDD (odds ratio 1.63, 95% confidence interval 1.12–2.30).ConclusionsThese findings provide epidemiologic evidence that some pediatric-onset neuropsychiatric disorders, including OCD, tic disorders, ADHD, and MDD, may be temporally related to prior streptococcal infections. Whether this is the result of a nonspecific stress response or secondary to an activation of the immune system remains to be determined.     

Correlates of comorbid anxiety and externalizing disorders in childhood obsessive compulsive disorder

The present study examines the influence of diagnostic comorbidity on the demographic, psychiatric, and functional status of youth with a primary diagnosis of obsessive compulsive disorder (OCD). Two hundred and fifteen children (ages 5–17) referred to a university-based OCD specialty clinic were compared based on DSM-IV diagnostic profile: OCD without comorbid anxiety or externalizing disorder, OCD plus anxiety disorder, and OCD plus externalizing disorder. No age or gender differences were found across groups. Higher OCD severity was found for the OCD + ANX group, while the OCD + EXT group reported greater functional impairment than the other two groups. Lower family cohesion was reported by the OCD + EXT group compared to the OCD group and the OCD + ANX group reported higher family conflict compared to the OCD + EXT group. The OCD + ANX group had significantly lower rates of tic disorders while rates of depressive disorders did not differ among the three groups. The presence of comorbid anxiety and externalizing psychopathology are associated with greater symptom severity and functional and family impairment and underscores the importance of a better understanding of the relationship of OCD characteristics and associated disorders. Results and clinical implications are further discussed.     

Clinical phenomenology and phenotype variability in Tourette syndrome

Tourette syndrome (TS) is a neurodevelopmental disorder with a rich phenomenology that includes simple and complex motor and vocal tics as well as multiple comorbidities. From a nosological perspective, it is evident that a continuum of tic severity exists, of which TS is the most severe and rare form, while transient tics and chronic tics represent milder forms. From a psychopathology perspective, TS is often concurrent with obsessive–compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD); these disorders appear to define TS “types” TS only, TS+OCD, and TS+OCD+ADHD. Additional clinical aspects of TS include more frequent than expected occurrence of anger episodes, anxiety disorders, mood disorders, impulse control disorders, learning disorders, and pervasive developmental disorders. Data reduction techniques have been used more recently to define a “simple” and “complex” tic symptom clusters or factors. Phenomenologic approaches can be used in TS to guide future pathophysiologic research.     

Tic exacerbation and precipitation during atomoxetine treatment in two children with attention-deficit hyperactivity disorder

Stimulants have been the mainstay of treatment for children with Attention-deficit/hyperactivity Disorder (ADHD). However, stimulants have been controversially purported to precipitate and exacerbate tics. Atomoxetine, a selective norepinephrine inhibitor, was introduced as a safe non-stimulant alternative treatment for ADHD children with comorbid tics or TS. We are presenting two children with ADHD, in which atomoxetine, at relatively low doses, exacerbated and precipitated tics. The diagnoses of ADHD and tic disorder were based on clinical observations and standardized rating scales. Case 1, an 8-year-old boy, had history of stimulant-induced tics. This child was placed on atomoxetine reported to be safe for patients with tics. This patient's tic control was adequate prior to atomoxetine treatment. However, while on atomoxetine, the patient promptly experienced tic exacerbation. Case 2, a 6-year-old boy, had no previous history of stimulant therapy and was receiving citalopram due to a comorbid anxiety disorder. Atomoxetine was initiated for the treatment of ADHD with improvement in the ADHD symptoms. But, upon a mild dose increase, the patient presented tic precipitation consisting primarily of neck twitches. Both cases experienced a decrease in tic activity when atomoxetine was discontinued, but tics did not fully resolve, causing psychosocial disturbance. Atypical neuroleptics were used with good results. Periodic assessments of the need for continued neuroleptic treatment were emphasized. These two children exemplify atomoxetine's potential to exacerbate and precipitate tics in children with ADHD. Independent controlled studies are needed to determine if atomoxetine should be used in children with ADHD and comorbid tic disorders or TS.     

Association between Tourette syndrome and comorbidities in Japan

The purpose of this study was (1) to document cases of Tourette syndrome (TS) with comorbidities such as obsessive–compulsive symptoms (OCS) and hyperkinetic disorder (HD), and (2) to examine differences in clinical characteristics between TS patients with OCS and HD and those without these comorbidities. The subjects in the study were 88 Japanese TS patients (67 males and 21 females; mean age: 15.2 years) who were treated by 31 clinicians including psychiatrists and pediatricians. Data on tic symptoms, comorbidities and severity were scrutinized. OCS were present in 42.0% of the subjects, while HD accounted for 28.4%. In the TS + OCS and/or HD group, coprophenomana, impulsiveness/aggression, school refusal, self-injurious behaviors (SIB), and clumsiness were significantly more frequent than in the TS-only group. Also, tic symptoms and impairment during the worst period was significantly severer in the TS + OCS and/or HD than in the TS-only group. When the age-matched TS + all OCS group (i.e., the young TS + OCS and TS + OCS + HD group) was compared with the TS-only group, it was found that the rates of impulsiveness/aggression, school refusal and SIB were significantly higher and the degree of global severity was significantly more intense in the young TS + all OCS group than in the TS-only group. The impact to clinical characteristics of TS from OCS was suggested to be slightly greater than that from HD. There was little ethnic difference in TS pathogenesis in terms of the impact of comorbidities. Further investigation is required to gain deeper insights into the relationships between TS, OCD or OCS and HD.     

Children and adolescents with obsessive-compulsive disorder and comorbid attention-deficit/hyperactivity disorder: preliminary results of a prospective follow-up study

Summary. In the present study, we have investigated the influence of comorbid attention deficit hyperactivity disorder (ADHD) on early onset obsessive compulsive disorder (OCD). For that purpose, we compared 20 patients with “OCD with ADHD” and 20 randomly selected patients with “OCD without ADHD”. “OCD with ADHD” patients tended to show an earlier age of OCD onset, a higher severity of symptoms and a higher persistence rate than OCD patients without ADHD. Both groups appear to develop different patterns of comorbid disorders. The first two authors have equally contributed to the study. Correspondence: Susanne Walitza, Department of Child and Adolescent Psychiatry and Psychotherapy, University of Würzburg, Füchsleinstr. 15, 97080 Würzburg, Germany