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Pre- and perinatal complications have been implicated in the onset and clinical expression of Tourette syndrome albeit with considerable inconsistencies across studies. Also, little is known about their role in co-occurring obsessive-compulsive disorder (OCD) and attention-deficit/hyperactivity disorder (ADHD) in individuals with a tic disorder. Therefore, we aimed to investigate the role of pre- and perinatal complications in relation to the presence and symptom severity of chronic tic disorder and co-occurring OCD and ADHD using data of 1113 participants from the Tourette International Collaborative Genetics study. This study included 586 participants with a chronic tic disorder and 527 unaffected family controls. We controlled for age and sex differences by creating propensity score matched subsamples for both case-control and within-case analyses. We found that premature birth (OR = 1.72) and morning sickness requiring medical attention (OR = 2.57) were associated with the presence of a chronic tic disorder. Also, the total number of pre- and perinatal complications was higher in those with a tic disorder (OR = 1.07). Furthermore, neonatal complications were related to the presence (OR = 1.46) and severity (b = 2.27) of co-occurring OCD and also to ADHD severity (b = 1.09). Delivery complications were only related to co-occurring OCD (OR = 1.49). We conclude that early exposure to adverse situations during pregnancy is related to the presence of chronic tic disorders. Exposure at a later stage, at birth or during the first weeks of life, appears to be associated with co-occurring OCD and ADHD.

Objective: Phenotypic heterogeneity in Tourette syndrome is partly due to complex genetic relationships among Tourette syndrome, obsessive-compulsive disorder (OCD), and attention deficit hyperactivity disorder (ADHD). Identifying symptom-based endophenotypes across diagnoses may aid gene-finding efforts.Method: Assessments for Tourette syndrome, OCD, and ADHD symptoms were conducted in a discovery sample of 3,494 individuals recruited for genetic studies. Symptom-level factor and latent class analyses were conducted in Tourette syndrome families and replicated in an independent sample of 882 individuals. Classes were characterized by comorbidity rates and proportion of parents included. Heritability and polygenic load associated with Tourette syndrome, OCD, and ADHD were estimated.Results: The authors identified two cross-disorder symptom-based phenotypes across analyses: symmetry (symmetry, evening up, checking obsessions; ordering, arranging, counting, writing-rewriting compulsions, repetitive writing tics) and disinhibition (uttering syllables/words, echolalia/palilalia, coprolalia/copropraxia, and obsessive urges to offend/mutilate/be destructive). Heritability estimates for both endophenotypes were high and statistically significant (disinhibition factor=0.35, SE=0.03; symmetry factor=0.39, SE=0.03; symmetry class=0.38, SE=0.10). Mothers of Tourette syndrome probands had high rates of symmetry (49%) but not disinhibition (5%). Polygenic risk scores derived from a Tourette syndrome genome-wide association study (GWAS) were significantly associated with symmetry, while risk scores derived from an OCD GWAS were not. OCD polygenic risk scores were significantly associated with disinhibition, while Tourette syndrome and ADHD risk scores were not.Conclusions: The analyses identified two heritable endophenotypes related to Tourette syndrome that cross traditional diagnostic boundaries. The symmetry phenotype correlated with Tourette syndrome polygenic load and was present in otherwise Tourette-unaffected mothers, suggesting that this phenotype may reflect additional Tourette syndrome (rather than OCD) genetic liability that is not captured by traditional DSM-based diagnoses. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics—rapid, repetitive, stereotyped movements or vocalizations. Tourette syndrome typically has a prepubertal onset, and boys are more commonly affected than girls. Symptoms usually begin with transient bouts of simple motor tics. By age 10 years, most children are aware of nearly irresistible somatosensory urges that precede the tics. These urges likely reflect a defect in sensorimotor gating because they intrude into the child's conscious awareness and become a source of distraction and distress. A momentary sense of relief typically follows the completion of a tic. Over the course of hours, tics occur in bouts, with a regular intertic interval. Tics increase during periods of emotional excitement and fatigue. Tics can become ‘complex’ in nature and appear to be purposeful. Tics can be willfully suppressed for brief intervals and can be evoked by the mere mention of them. Tics typically diminish during periods of goal-directed behavior, especially those that involve both heightened attention and fine motor or vocal control, as occur in musical and athletic performances. Over the course of months, tics wax and wane. New tics appear, often in response to new sources of somatosensory irritation, such as the appearance of a persistent vocal tic (a cough) following a cold. Over the course of years, tic severity typically peaks between 8 and 12 years of age. By the end of the second decade of life, many individuals are virtually tic free. Less than 20% of cases continue to experience clinically impairing tics as adults. Tics rarely occur in isolation, and other coexisting conditions—such as behavioral disinhibition, hypersensitivity to a broad range of sensory stimuli, problems with visual motor integration, procedural learning difficulties, attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depression, anxiety, and emotional instability—are often a greater source of impairment than the tics themselves. Emerging behavioral treatments of Tourette syndrome are based in part on an understanding of the moment-to-moment experience of somatosensory urges and motor response. With identification of specific genes of major effect and advances in our understanding of the neural circuitry of sensorimotor gating, habit formation, and procedural memory—together with insights from postmortem brain studies, in vivo brain imaging, and electro-physiologic recordings—we might be on the threshold of a deeper understanding of the phenomenology and natural history of Tourette syndrome. [ABSTRACT FROM AUTHOR]

Background: Previous studies have provided preliminary serological evidence supporting the theory that symptoms of tic disorders or obsessive-compulsive disorder (OCD) may be sequelae of prior streptococcal infection. It is unclear, however, whether previously reported associations with streptococcal infection were obscured by the presence of diagnostic comorbidities. It is also unknown whether streptococcal infection is associated in vivo with anatomical alterations of the brain structures that have been implicated in the pathophysiology of these disorders. Methods: Antistreptococcal antibody titers were measured in 105 people diagnosed as having CTD, OCD, or attention-deficit/hyperactivity disorder (ADHD) and in 37 community controls without a disorder. Subjects were unselected with regard to their history of streptococcal exposure. Basal ganglia volumes were measured in 113 of these subjects (79 patients and 34 controls). Results: A DSM-IV diagnosis of ADHD was associated significantly with titers of 2 distinct antistreptococcal antibodies, antistreptolysin O and anti–deoxyribonuclease B. These associations remained significant after controlling for the effects of CTD and OCD comorbidity. No significant association was seen between antibody titers and a diagnosis of either CTD or OCD. When basal ganglia volumes were included in these analyses, the relationships between antibody titers and basal ganglia volumes were significantly different in OCD and ADHD subjects compared with other diagnostic groups. Higher antibody titers in these subjects were associated with larger volumes of the putamen and globus pallidus nuclei. Conclusions: These findings suggest that the prior reports of an association between antistreptococcal antibodies and either CTD or OCD may have been confounded by the presence of ADHD. They also support the hypothesis that in susceptible persons who have ADHD or OCD, chronic or recurrent streptococcal infections are associated wit... [ABSTRACT FROM AUTHOR]

The article presents a study that aims to determine the role of antecedent streptococcal infection in increasing the risk of diagnosis of disported in children including obsessive-compulsive disorder and attention-deficit/hyperactivity disorder. It examines the number of streptococcal infections recorded after the incident diagnosis of the disorders. It explores the specificity of new-onset of the disorders as sequelae of streptococcal infection with the use of a comparable association analysis. Information on the results of the study is also presented.

Objective: 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.Method: 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.Results: 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 (pConclusions: 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. [ABSTRACT FROM AUTHOR]

Objective: Tourette's disorder (TD) and autism spectrum disorder (ASD) share clinical features and possibly an overlapping etiology. The aims of this study were to examine ASD symptom rates in participants with TD, and to characterize the relationships between ASD symptom patterns and TD, obsessive-compulsive disorder (OCD), and attention-deficit/hyperactivity disorder (ADHD).Method: Participants with TD (n = 535) and their family members (n =234) recruited for genetic studies reported TD, OCD, and ADHD symptoms and completed the Social Responsiveness Scale Second Edition (SRS), which was used to characterize ASD symptoms.Results: SRS scores in participants with TD were similar to those observed in other clinical samples but lower than in ASD samples (mean SRS total raw score = 51; SD = 32.4). More children with TD met cut-off criteria for ASD (22.8%) than adults with TD (8.7%). The elevated rate in children was primarily due to high scores on the SRS Repetitive and Restricted Behaviors (RRB) subscale. Total SRS scores were correlated with TD (r = 0.27), OCD (r = 0.37), and ADHD (r = 0.44) and were higher among individuals with OCD symptom-based phenotypes than for those with tics alone.Conclusion: Higher observed rates of ASD among children affected by TD may in part be due to difficulty in discriminating complex tics and OCD symptoms from ASD symptoms. Careful examination of ASD-specific symptom patterns (social communication vs. repetitive behaviors) is essential. Independent of ASD, the SRS may be a useful tool for identifying patients with TD with impairments in social communication that potentially place them at risk for bullying and other negative sequelae. [ABSTRACT FROM AUTHOR]