Behavior disorder and attention deficits in boys with Tourette syndrome

Tourette syndrome and other tic disorders of childhood

Tics are repetitive, patterned, and nonrhythmic movements or vocalizations/audible sounds that are misplaced in context. Phenomenology and characteristics of tics (e.g., premonitory urge, suppressibility) differentiate them from compulsions, stereotypies, functional tic-like behaviors, and other types of hyperkinetic movement disorders. With a prevalence of approximately 1% in school-aged boys, Tourette syndrome (TS) is considered a common childhood-onset neurodevelopmental disorder, defined by the combination of at least two motor tics and at least one phonic tic lasting more than 1 year. TS is a highly heritable disorder, with a wide spectrum of severity. In some individuals, tics can cause pain, distress, functional impairment, or stigmatization. About 90% of individuals with TS have at least one mental health comorbidity (attention-deficit/hyperactivity disorder, obsessive-compulsive disorder, anxiety/depressive disorders). These comorbidities significantly impact patients' quality of life and must therefore be screened and managed accordingly in this population. Treatment of tics is based on behavioral therapies targeting tics (habit reversal training included in the comprehensive behavioral intervention for tics, and exposure and response prevention for tics), in association with medication if needed (e.g., alpha-2-agonists, second-generation antipsychotics). Deep brain stimulation is considered an experimental option in the most severe, treatment-resistant patients. In adulthood, less than 25% of individuals still have moderate or severe tics.

Psychopathology in boys with Tourette syndrome: Effects of age on the relationship between psychological and physical symptoms

Tourette syndrome (TS), a neuropsychiatric disorder that presents in childhood and is characterized by recurrent tics, is often associated with a variety of psychological problems. Most studies of concomitant problems have focused on psychiatric comorbidity, with less attention paid to nonsyndrome-specific or subsyndromal emotional and behavioral difficulties. Moreover, little is known about the factors that influence the specificity or severity of psychological problems. We hypothesized that level and type of psychological problem would be influenced by both severity of illness and developmental period. Children with severe tics were predicted to show increased levels of externalizing (undercontrolled) behavior, whereas adolescents with severe tics were predicted to show increased levels of internalizing (overcontrolled) behavior. Forty-one boys with TS were rated by their parents for tic severity (simple and complex motor tics) and psychological symptoms (Connors Parent Symptom Questionnaire and the Child Behavior Checklist). Results partially confirmed the hypothesis, indicating that greater illness severity was associated with greater psychological disturbance, but only in the younger subjects. Among the adolescents, even those with mild tics demonstrated relatively high levels of psychological symptoms. However, there was no indication that developmental period was related to the specific type of problem manifested. Regardless of age, patients with severe tics domonstrated high levels of externalizing behavior, and relatively high levels of internalizing behavior were also seen. Results are discussed in terms of the developmental factors that might influence the relationship between psychological and physical symptoms in children with TS.

The relationship between tourette syndrome, attention deficit hyperactivity disorder, and stimulant medication: a critical review

The relationship between tic disorders and attention deficit hyperactivity disorder (ADHD) is of great clinical importance because both disorders can lead to emotional, social, and academic difficulties. To further complicate this interrelationship is the concern that the use of psychostimulant medication to treat ADHD will help the hyperactivity and attention problems but will lead to the onset of tics or will worsen preexisting tics. The first part of this review investigates how often Tourette syndrome (TS) is associated with ADHD and finds that ADHD has been reported in 35% to 90% of children with TS. The second part of the review looks at whether the ADHD seen in TS is the same as in children who do not have tics. Recent studies lead to the conclusion that the ADHD seen in TS is the same, although the attentional difficulties seen in TS are influenced also by the distraction of the tics themselves as well as by internal distractions such as is seen in comorbid anxiety or obsessive-compulsive behavior. The final part of the review investigates the question of whether psychostimulants worsen or cause tics. Twenty-two studies were found that investigated this possible relationship. Earlier studies were confounded by the natural pattern seen in TS in which tics spontaneously wax and wane in occurrence, intensity, and frequency. More recent double-blind, placebo-controlled studies have shown that psychostimulants are equally effective in improving ADHD symptoms whether the disorder is associated with tics or not. When group data are analyzed, there is no significant increase in tics when psychostimulants are used in patients with tics compared with controls. Individual patients, however, may experience an increase in tics. This increase is not appreciated in analysis of group data. In conclusion, it is medically appropriate to provide treatment with psychostimulant medication in persons with tics where the ADHD symptoms are significantly disturbing their quality of life.

Clinical significance of tics and attention-deficit hyperactivity disorder (ADHD) in children with pervasive developmental disorder

The goal of this study was to examine the clinical significance of co-occurring tics and attention-deficit hyperactivity disorder (ADHD) as indicators of a more complex symptomatology in children with and without pervasive developmental disorder. Parents and teachers completed a Diagnostic and Statistical Manual of Mental Disorders-IV-referenced rating scale for 3- to 5- (n = 182/135) and 6- to 12- (n = 301/191) year-old children with pervasive developmental disorder and clinic controls, respectively. The percentage of children with tic behaviors varied with age: preschoolers (25%, 44%) versus elementary schoolchildren (60%, 66%) (parent and teacher ratings, respectively). For many psychiatric symptoms, screening prevalence rates were highest for the ADHD + tics group and lowest for the group with symptoms of neither, but the pattern of group differences varied by age group and informant. In general, there were few differences between the ADHD only and tics only groups. The pattern of ADHD/tic group differences was similar for both children with and without pervasive developmental disorder. We concluded that these findings support the notion that the co-occurrence of ADHD and tics is an indicator of a more complex psychiatric symptomatology in children with pervasive developmental disorder.

Tourette's syndrome: are stimulants safe?

Clinicians commonly encounter children with comorbid attention deficit hyperactivity disorder (ADHD) and the tic disorder Tourette's syndrome. The pharmacologic treatment of children with this particular combination of conditions has been problematic because of long-standing warnings against using psychostimulants due to concerns about worsening tics. The basis for these warnings was anecdotal clinical observations. A recent group of placebo-controlled, double-blinded clinical trials have consistently shown that certain stimulants, particularly methylphenidate and dextroamphetamine, are effective, well tolerated, and safe when administered to treat ADHD in children with tics. Methylphenidate appears to be the best-tolerated stimulant compound, with tics often lessening during treatment.

Psychiatric disorders in individuals with pervasive developmental disorder

Pervasive developmental disorders (PDD) refer to the group of heterogeneous conditions that make up a continuum or spectrum of autistic disorders and share a core triad of impairments consisting of qualitative disturbances in social interaction and verbal and nonverbal communication and imagination. It has long been believed that the prevalence of autism was 2-4 per 10,000 children. However, studies using broader definitions of autistic disorder have suggested that the prevalence of autism spectrum disorder may be as high as 90 per 10,000 and that a greater proportion of individuals with PDD have intellectual levels above 70. Clinicians and researchers have commented on the apparent increase in prevalence of the disorder and have offered a number of explanations, including better recognition and diagnosis of the autism spectrum of disorders and a real increase in the disturbance. It is being increasingly recognized that individuals with PDD are at risk for a wide array of psychiatric disturbances, including affective disorder, anxiety disorders, schizophrenia-like psychosis, aggression, antisocial behavior, and Tourette's disorder (TD). Evidence indicates that PDD is significantly related to the comorbid psychiatric disorders and TD. Because PDD is not rare, individuals with autism spectrum disorder may represent significant subgroups of severely emotionally disturbed patients referred for psychiatric treatment. Because of lack of awareness that the clinical manifestations of PDD are heterogeneous and often mild and that comorbid psychiatric disturbances may obscure the symptoms of the developmental disorder, the diagnosis of PDD may be missed. Implications for practicing clinicians are discussed.

Anxiety and depression symptoms and response to methylphenidate in children with attention-deficit hyperactivity disorder and tic disorder

This study examined response to methylphenidate in children with attention-deficit/hyperactivity disorder (ADHD) and chronic multiple tic disorder. The primary goal was to determine if children with anxiety or depression symptoms showed a less favorable response to treatment. Subjects were 38 prepubertal children who participated in an 8-week, double-blind, placebo-controlled, methylphenidate crossover evaluation. Treatment effects were assessed with direct observations of child behavior in public school and clinic settings; rating scales completed by parents, teachers, and clinicians; and laboratory analogue tasks. There was little evidence (group data) that children with anxiety or depression symptoms responded in a clinically different manner to methylphenidate than youngsters who did not exhibit these symptoms, particularly in school observations of the core features of ADHD. Seeming differences between children with and without comorbid anxiety or depression symptoms and drug response are likely explained by differences in pretreatment levels of negativistic behaviors (i.e., symptoms of oppositional defiant disorder or conduct disorder). Methylphenidate appears to be effective for the management of ADHD behaviors in children with mild to moderate anxiety or depression symptoms; nevertheless, much research remains to be performed in this area.

Comparison of internalizing and externalizing symptoms in children with attention-deficit hyperactivity disorder with and without comorbid tic disorder

This study examined the relation between internalizing and externalizing symptoms in two groups of prepubertal boys (with and without multiple chronic tic disorder) with diagnosed attention-deficit hyperactivity disorder (ADHD). Parents and teachers completed the Child Behavior Checklist (CBCL) and Teacher's Report Form (TRF), respectively. Children were carefully evaluated for the absence of a chronic tic disorder. Boys with ADHD and chronic multiple tic disorder (ADHD/+tics) received significantly higher (p = .0032, Bonferroni correction) scores for the Anxious/Depressed, Thought Problems, and Attention Problem scales of the CBCL and the Delinquent Behavior, Thought Problems, and Somatic Complaints scales of the TRF than did boys without chronic tic disorder (ADHD/-tics). Although many of the individual items that differentiated (p < .05) the two groups of boys pertained to behaviors that characterize motor tics, obsessions, or compulsions, the ADHD/+tics group exhibited higher rates of anxious behavior (CBCL) and obscene language (TRF) than did the ADHD/-tics group. Anxiety/depressive symptoms were associated with aggressive/oppositional behavior in both samples. Children with mild tic disorder were more similar (CBCL) to ADHD/-tics boys than they were to children with more severe tic disorder. The relatively higher rate of comorbidity in the ADHD/+tics group suggests that tics may be a marker for more severe symptomatology in clinic-referred samples of children with ADHD. Furthermore, these data suggest that it is not the presence, per se, but rather the severity of tic disorder that is associated with higher rates of emotional and behavioral disturbances.

Stimulant medication withdrawal during long-term therapy in children with comorbid attention-deficit hyperactivity disorder and chronic multiple tic disorder

OBJECTIVES

In this study we examined changes in attention-deficit hyperactivity disorder behaviors and motor and vocal tics during withdrawal from long-term maintenance therapy with stimulant medication.

METHODS

Subjects were 19 children with attention-deficit hyperactivity disorder and chronic tic disorder who had received methylphenidate (n = 17) or dextroamphetamine (n = 2) for a minimum of 1 year. Children were switched to placebo under double-blind conditions. Treatment effects were assessed by using direct observations of child behavior in a simulated (clinic-based) classroom and behavior rating scales completed by parents and clinician.

RESULTS

There was no change (group data) in the frequency or severity of motor tics or vocal tics during the placebo condition compared with maintenance dose of stimulant medication (ie, no evidence of tic exacerbation while receiving medication or of a withdrawal reaction). There was no evidence of tic exacerbation in the evening as a rebound effect. Treatment with the maintenance dose was also associated with behavioral improvement in attention-deficit hyperactivity disorder behaviors, indicating continued efficacy.

CONCLUSIONS

Abrupt withdrawal of stimulant medication in children receiving long-term maintenance therapy does not appear to result in worsening of tic frequency or severity. Nevertheless, these findings do not preclude the possibility of drug withdrawal reactions in susceptible individuals.

Tourette's syndrome and psychopathology in a child psychiatry setting

Prior investigations of psychopathology among children with Tourette's syndrome (TS) have rarely used child psychiatry samples and sophisticated personality instruments.

OBJECTIVE

To produce an objectively derived composite TS personality profile and to determine the rate of particular problems in a TS psychiatry sample compared with children with out TS from the same clinical practice.

METHOD

Children (n = 33) referred to child psychiatrists because of emotional and behavior problems who were subsequently also found to meet DSM-III-R criteria for TS were assessed by the Personality Inventory for Children.

RESULTS

Children with TS expressed high rates of psychopathology overall (composite 2.7 SD elevated) with depression, anxiety, and peculiar behavior having the highest values; depression occurred most frequently (73%), and attention-deficit hyperactivity disorder (55%) was no more common than among comparison group children and conduct problems (18%) were rarer. "Depression, anxiety, tension, and excessive worry" were characteristic of the actuarially derived modal TS personality.

CONCLUSIONS

The prevalence and manifestations of psychopathology of children with TS in a child psychiatry practice are not identical with those reported in the literature. Child psychiatrists should be particularly vigilant of depressive symptoms and expect to encounter relatively few conduct problems compared with children without TS. Establishing "local prevalence rates" for children with TS seeking psychiatric evaluation can help guide the diagnostician and make diagnosis more assured.

Children with ADHD and tic disorder and their classmates: behavioral normalization with methylphenidate

OBJECTIVES

To examine behavioral differences between children with attention-deficit hyperactivity disorder (ADHD) and tics and their peers and the extent to which methylphenidate (0.1, 0.3, and 0.5 mg/kg) normalized the behavior of probands and indirectly influenced the behavior of peers (treatment spillover).

METHOD

Thirty-four prepubertal children with ADHD and chronic tic disorder (who were participating in a double-blind, placebo-controlled methylphenidate evaluation) and their peers were observed for approximately 20 hours in the school setting (classroom seatwork activities, lunchroom, and playground).

RESULTS

Children with ADHD and tics were more inattentive and more disruptive in the classroom and more aggressive in all school settings than their peers. Although treatment with methylphenidate made probands less easily distinguished from their peers (normalization), many children still scored in the deviant range for at least one ADHD behavior when receiving the 0.5-mg/kg dose. There was little evidence that peer behavior improved as a function of the proband's dose of medication.

CONCLUSIONS

Although conventional doses of methylphenidate produced dramatic clinical improvement in ADHD-related behavior, complete behavioral normalization is often not attained.

Associated psychopathology in children with both ADHD and chronic tic disorder

OBJECTIVE

To examine the relation between severity of tic disorder and comorbid psychopathology in 47 prepubertal children with tic disorder who were referred for clinical evaluation of and treatment for attention-deficit hyperactivity disorder (ADHD), oppositional behaviors, and aggressive behaviors.

METHOD

Parents and teachers completed the Child Behavior Checklist (CBCL) and Teacher's Report Form (TRF) for each child.

RESULTS

Seventy-five percent of the sample was in the clinical range in at least two categories of psychopathology. When the children were divided into two groups on the basis of tic severity, significantly higher scores were obtained for children with more severe tics on the narrow-band Depressed, Uncommunicative, Obsessive-Compulsive, and Aggressive scales, and the broad-band internalizing scale of the CBCL. The severity groups did not differ on TRF scores. Children who were more aggressive also received higher CBCL scores.

CONCLUSIONS

The findings from this study suggest that the severity of chronic tics is a clinical indicator of complex psychopathology in children with ADHD who are referred for psychiatric evaluation.

Executive functions and developmental psychopathology

In this paper, we consider the domain of executive functions (EFs) and their possible role in developmental psychopathologies. We first consider general theoretical and measurement issues involved in studying EFs and then review studies of EFs in four developmental psychopathologies: attention deficit hyperactivity disorder (ADHD), conduct disorder (CD), autism, and Tourette syndrome (TS). Our review reveals that EF deficits are consistently found in both ADHD and autism but not in CD (without ADHD) or in TS. Moreover, both the severity and profile of EF deficits appears to differ across ADHD and autism. Molar EF deficits are more severe in the latter than the former. In the few studies of more specific EF tasks, there are impairments in motor inhibition in ADHD but not in autism, whereas there are impairments in verbal working memory in autism but not ADHD. We close with a discussion of implications for future research.

Behavioral problems and severity of tics

This study examined the incidence of behavioral symptoms in youngsters with tic disorders. A total of 186 patients were studied using the Child Behavior Checklist and a Motor/Vocal Tic Severity Scale. The relationship between tic severity and the frequency of behavioral symptoms was found to be not simply linear, but influenced by the presence of patients without significant behavioral problems in spite of severe tics (resilient patients) and patients with very negative adjustment although their tic disorder was mild (vulnerable patients). Behavioral problems were not related to age. Patients who were receiving medication showed behavioral problems of different severity from those who were not receiving such agents; this result emphasizes the need for future studies to consider carefully the effects of medication.

Genetic factors in substance abuse based on studies of Tourette syndrome and ADHD probands and relatives. II. Alcohol abuse

Prior studies have suggested childhood attention deficit hyperactivity disorder (ADHD) as a risk factor for alcohol abuse in adults. Gilles de la Tourette Syndrome, a hereditary tic and impulse disorder, is clinically and genetically similar to ADHD. To examine the hypothesis that individuals carrying the Gts gene are at increased risk to develop alcohol use problems, the same TS (Tourette Syndrome) and ADHD probands, relatives and controls used in the prior study of drug abuse were also studied using a structured questionnaire based on the Diagnostic Interview Schedule and the MAST test. The frequency of a positive response to any of 16 different questions concerning alcohol abuse showed a highly significant increase with increased genetic loading for Gts and ADHD genes. The percentage of more than one positive response in TS probands was markedly influenced by the presence of comorbid ADHD, discipline, obsessive-compulsive or drug abuse problems. Comorbid drug abuse problems were the best predictor of alcohol abuse problems. These results suggest that the genes responsible for TS and ADHD play an important role in alcohol abuse/dependence as well as drug abuse/dependence. One of the elements common to all of these disorders may be mutant genes affecting serotonin metabolism.

Tourette syndrome: associated symptoms and most disabling features

Four hundred forty-six patients with Tourette Syndrome (TS) and/or their parents completed a 52-item self-report survey about vocal and motor tics, and the frequency of associated co-morbid conditions of aggression, obsessions and compulsions, attentional problems, sleep disturbance, mood disturbance, anxiety, and self-mutilative behaviours which have been frequently reported in the literature on TS. Respondents also responded to an open-ended question regarding the most disabling aspects of TS. Results were analyzed within two age groups; under 18 years of age (N = 245) and 18 years of age or older (N = 177). Tics and associated conditions were the most frequently reported disabling aspect by both age groups. Subjects under age 18, however, reported significantly more frequent problems with hyperactivity, temper control, aggressive behaviours and sleepwalking than adults with TS.

Tourette's syndrome, Part I: Definition and diagnosis

Tourette's syndrome (TS) is a neuropsychiatric disorder characterized by a changing repertoire of motor and phonic tics that typically begin in childhood and exhibit a fluctuating course. Obsessive-compulsive symptoms and problems of inattention, overactivity, and impulsiveness are present in some cases. Historically, TS has been viewed as a severe disorder. However, data from epidemiologic and family-genetic studies indicate that it shows a wide range of severity. This article, the first of two parts, examines the current notions concerning the origin, pathophysiology, and diagnosis of TS. The second article will present three cases and describe contemporary approaches to treatment.

Tourette syndrome attributed to frontal lobe dysfunction: numerous etiologies involved

The etiology of Tourette Syndrome (TS) according to prevailing views is unknown; there is evidence for both familial and sporadic cases. The author theorizes that abnormal discharges in the frontal lobes comprise the "final common dysfunction" that results in numerous phenomena labelled Tourette syndrome. Facial, vocal, and other motor symptoms of TS are catalogued in parallel with facial, vocal, and body movements that occur during frontal lobe seizures. The variety of etiologies that cause frontal lobe seizures--when applied to TS--can account more readily for heterogeneity of clinical presentations, the numerous "dual diagnosis" cases, and differential response to medication than can a single-gene theory.

Clinical management of attention deficit hyperactivity disorder

This article reviews current approaches to the diagnosis and management of children with attention deficit hyperactivity disorder in a multidisciplinary setting. The physician's role in terms of data collection, formulation of the diagnosis, and discussion of findings with the parents and child is reviewed. The use of psychostimulants in this condition is reviewed, and some case vignettes are presented.

CNS stimulant controversies

Controversies in the use of central nervous system stimulant medications in children with attention deficit hyperactivity disorder are discussed. Diagnostic issues, age of optimal use, side effects, effects on learning and ethical considerations are current issues. An animal model for the effects of chronic long-term high dose regimes is proposed.

Hypothesis: homozygosity in Tourette syndrome

We review evidence suggesting that many individuals with Tourette syndrome (TS) may be homozygous for a "Tourette syndrome" gene. This is based on experience with pedigrees on 1,200 TS families, comparison of the occurrence of tics or associated behaviors such as obsessive-compulsive behavior, panic attacks, attention deficit hyperactivity disorder, and/or severe alcohol or drug abuse, on both the maternal and paternal side in 170 TS families compared to control families, biochemical studies of blood serotonin and tryptophan levels, and other evidence. These observations suggest the inheritance in TS may be best described as semi-dominant, semi-recessive. Some of the implications of this proposal are discussed.

Methylphenidate treatment of attention-deficit hyperactivity disorder in boys with Tourette's syndrome

The effects of methylphenidate on four boys diagnosed as attention-deficit hyperactivity disorder (ADHD) and Tourette's syndrome (TS) were examined under single-blind, placebo-controlled conditions. Clinical ratings and playroom observations showed improvement in ADHD symptoms with methylphenidate. Results also indicated that methylphenidate had no untoward effects on the frequency of tic occurrence. In all four children, the highest dose resulted in improved classroom ratings of tics compared with initial placebo treatment. In three cases, mild tic exacerbation was reported for a lower dose. Because variability of tic status was observed in the experimental conditions, the findings suggest the possibility that tic response was independent of clinical doses of methylphenidate. The findings were also consistent with the theory that methylphenidate, a dopamine agonist, might effect tic status by altering dopamine receptor sensitivity. Further investigation of these effects is indicated, given the efficacy of methylphenidate in treating ADHD symptoms of TS patients.