Obsessive-compulsive symptom dimensions in affected sibling pairs diagnosed with Gilles de la Tourette syndrome

Clinical characteristics of probands with obsessive-compulsive disorder from simplex and multiplex families

Genetic and non-genetic factors contribute to obsessive-compulsive disorder (OCD), with strong evidence of familial clustering. Genomic studies in psychiatry have used the concepts of families that are "simplex" (one affected) versus "multiplex" (multiple affected). Our study compares demographic and clinical data from OCD probands in simplex and multiplex families to uncover potential differences. We analyzed 994 OCD probands (501 multiplex, 493 simplex) from the Brazilian Research Consortium on Obsessive-Compulsive Spectrum Disorders (C-TOC). Clinicians administered the Structured Clinical Interview for DSM-IV (SCID-IV) to diagnose, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) to assess severity, and Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) to assess symptom dimensionality. Demographics, clinical history, and family data were collected. Compared to simplex probands, multiplex probands had earlier onset, higher sexual/religious and hoarding dimensions severity, increased comorbidity with other obsessive-compulsive-related disorders (OCRD), and higher family history of psychiatric disorders. These comparisons provide the first insights into demographic and clinical differences between Latin American simplex and multiplex families with OCD. Distinct clinical patterns may suggest diverse genetic and environmental influences. Further research is needed to clarify these differences, which have implications for symptom monitoring and management.

A dimensional perspective on the genetics of obsessive-compulsive disorder

This review covers recent findings in the genomics of obsessive-compulsive disorder (OCD), obsessive-compulsive symptoms, and related traits from a dimensional perspective. We focus on discoveries stemming from technical and methodological advances of the past five years and present a synthesis of human genomics research on OCD. On balance, reviewed studies demonstrate that OCD is a dimensional trait with a highly polygenic architecture and genetic correlations to multiple, often comorbid psychiatric phenotypes. We discuss the phenotypic and genetic findings of these studies in the context of the dimensional framework, relying on a continuous phenotype definition, and contrast these observations with discoveries based on a categorical diagnostic framework, relying on a dichotomous case/control definition. Finally, we highlight gaps in knowledge and new directions for OCD genetics research.

Developmental Considerations in Obsessive Compulsive Disorder: Comparing Pediatric and Adult-Onset Cases

There appear to be two peaks of incidence of Obsessive Compulsive Disorder (OCD), one with a pre-adolescent onset and another in early adulthood. As new cases are added, the cumulative prevalence of OCD increases, but the great majority of cases have an onset in youth. The notion that early onset OCD represents a unique developmental subtype of the disorder has been considered by many researchers based on several specific age-related factors. Ascertainment and early intervention in affected youth is critical to abbreviate the functional impairments associated with untreated illness. In this paper we review the clinical, familial and translational biomarker correlates seen in early onset OCD that support the notion of a developmental subtype and discuss implications for research and treatment aimed at this cohort. The importance of cognitive, academic and social development tasks of childhood and adolescence, illness-specific and familial factors, and immune-mediated inflammatory factors are discussed, with their implications for management.

Are There Familial Patterns of Symptom Dimensions in Obsessive-Compulsive Disorder?

Background: Obsessive-compulsive disorder (OCD) is a heterogeneous illness, and emerging evidence suggests that different symptom dimensions may have distinct underlying neurobiological mechanisms. We aimed to look for familial patterns in the occurrence of these symptom dimensions in a sample of families with at least two individuals affected with OCD. Methods: Data from 153 families (total number of individuals diagnosed with DSM-5 OCD = 330) recruited as part of the Accelerator Program for Discovery in Brain Disorders using Stem Cells (ADBS) was used for the current analysis. Multidimensional Item Response Theory (IRT) was used to extract dimensional scores from the Yale-Brown Obsessive-Compulsive Scale (YBOCS) checklist data. Using linear mixed-effects regression models, intra-class correlation coefficients (ICC), for each symptom dimension, and within each relationship type were estimated. Results: IRT yielded a four-factor solution with Factor 1 (Sexual/Religious/Aggressive), Factor 2 (Doubts/Checking), Factor 3 (Symmetry/Arranging), and Factor 4 (Contamination/Washing). All except for Factor 1 were found to have significant ICCs, highest for Factor 3 (0.41) followed by Factor 4 (0.29) and then Factor 2 (0.27). Sex-concordant dyads were found to have higher ICC values than discordant ones, for all the symptom dimensions. No major differences in the ICC values between parent-offspring and sib-pairs were seen. Conclusions: Our findings indicate that there is a high concordance of OCD symptom dimensions within multiplex families. Symptom dimensions of OCD might thus have significant heritability. In view of this, future genetic and neurobiological studies in OCD should include symptom dimensions as a key parameter in their analyses.

Association Between Obsessive-Compulsive Symptom Dimensions in Mothers and Psychopathology in Their Children

Background: The non-clinical presentation of obsessive-compulsive symptoms (OCS) in women may impact not only their daily lives and well-being but also increase the risk for emotional and behavioral problems in their children. This study aims to investigate the OCS dimension distribution in a large sample of mothers from a cohort of school age children and the association between these OCS dimensions with their own psychopathology, and with the presence of OCS and other psychopathology in their children. Method: Our final sample consisted of 2,511 mother-children dyads recruited from the elementary schools of two large cities. Throughout multiple regression analysis, we examined the correlations between demographic and clinical variables of mothers assessed by the Mini International Psychiatric Interview (MINI) and the Dimensional Yale-Brown Obsessive-Compulsive Scale-Short Version (DY-BOCS-SV) with children's psychopathology status reported by the Child Behavior Checklist (CBCL). Results: The overall prevalence of mothers who reported experiencing at least one OCS was 40% (N = 1,004). "Aggression/violence" was the most frequent symptom dimension (32.2%), followed by the "symmetry/ordering" (16.4%) and the "sexual/religious" dimensions (13.8%). There was a significant correlation between the presence of OCS and maternal psychopathology in general (p < 0.001, r = 0.397). Not only the presence but also the severity of the mother's OCS were strongly correlated to the total (p < 0.001), internalizing (p < 0.001), externalizing (p < 0.001), and OCS subscale scores (p < 0.001) on the CBCL. Conclusion: OCS dimensions are highly prevalent in women. Presence and severity of maternal OCS are related to children's psychopathology and behavioral problems.

Obsessive-Compulsive Disorder

PURPOSE OF REVIEW

This article reviews current knowledge regarding diagnosis, pathophysiology, and treatment trends in obsessive-compulsive disorder (OCD), a severe, underrecognized, and chronic condition frequently encountered in neurologic practice.

RECENT FINDINGS

With a lifetime prevalence estimated at 2.5%, OCD is a common condition that can also present comorbidly with neurologic disease. The core symptoms of OCD are obsessions and compulsions. Obsessions are intrusive repetitive thoughts, urges, images, or impulses that trigger anxiety and that the individual is not able to suppress. Compulsions are repetitive behaviors or mental acts occurring in response to an obsession with the intention of reducing the distress caused by obsessions. Neuroimaging, neuropsychological, and pharmacologic studies suggest that the expression of OCD symptoms is associated with dysfunction in a cortico-striato-thalamo-cortical circuit. Evidence-based treatments for OCD comprise pharmacotherapy and cognitive-behavioral therapy. Selective serotonin reuptake inhibitors (SSRIs) are the first-line drugs recommended for OCD, but significant differences exist in their use for OCD compared to their use for other mood and anxiety conditions, including the need for higher dosage, longer trials necessitated by a longer lag for therapeutic response, and typically lower response rates. Cognitive-behavioral therapy, based on the principles of exposure and response prevention, shows results superior to pharmacologic treatments with lower relapse rates on long-term follow-up and thus should be considered in the treatment plan of every patient with OCD.

SUMMARY

OCD and obsessive-compulsive symptoms are frequently encountered in the neurologic clinic setting and require a high index of suspicion to effectively screen for them and an illness-specific therapeutic approach.

A call for prevention and early intervention in obsessive-compulsive disorder

BACKGROUND

Evidence suggests that many people with obsessive-compulsive disorder (OCD) have subclinical symptoms years before the development of their disorder and that early treatment may reduce its severity.

AIM

To explore prevention and early intervention strategies for OCD.

METHODS

A narrative literature review was conducted.

RESULTS

The literature in relation to the prevention of OCD is sparse. Genetic and environmental factors appear to be relevant to the aetiology of OCD, for example, the observation that hoarding symptoms and contamination/cleaning symptoms are more likely to also be present in first-degree relatives. Psychoeducation and the reduction of family accommodation, that is the act of parents, siblings or partners accommodating to the high-risk individual's requests to comply with their compulsions, are promising areas for prevention and early intervention in high-risk groups. Tertiary prevention has also been limited by an inadequate number of trained clinicians to deliver evidence-based treatments.

CONCLUSIONS

Much more research is needed in relation to the prevention of OCD. There is limited scope for primary prevention with respect to biological aetiological factors, but there is potential for strategies addressing environmental factors (eg, family factors). The effectiveness of psychoeducation for parents with OCD as a primary prevention strategy for OCD in their children requires scientific evaluation. Improving access to effective treatments for OCD would also improve tertiary prevention.

Obsessive-compulsive symptoms in children with first degree relatives diagnosed with obsessive-compulsive disorder

Objective:

A first-degree relative affected by obsessive-compulsive disorder (OCD) and obsessive-compulsive symptoms (OCS) in childhood is an important risk factor for developing the disorder in adulthood. The relationship between a family history of OCD and the presence of OCS and its correlates in childhood is not well established.

Methods:

A total of 66 children whose parents or siblings have been diagnosed with OCD were assessed for the presence of OCS and clinical correlates.

Results:

Three children (4.5%) were reported to have received an OCD diagnosis and another 26 (39.4%) were identified as having OCS. Children with OCS had higher rates of coercive behavior and came from families with lower socioeconomic status. Contamination/cleaning dimension symptoms in the proband were associated with OCS in the assessed children.

Conclusion:

OCS are frequent among family members of individuals with OCD and are associated with socioeconomic status, coercive behaviors and proband contamination/cleaning symptoms. Future longitudinal studies should test the risk of developing OCD in association with these characteristics.

The familiality of specific symptoms of obsessive-compulsive disorder

This study aimed to assess whether a family history of specific OCD symptoms was associated with the same OCD symptoms in study participants. Participants were sampled from the Nepean OCD study (N=206) and were assessed with the Yale-Brown Obsessive-Compulsive Scale Symptom Checklist (YBOCS-SC) and the Vancouver Obsessional Compulsive Inventory (VOCI) in order to determine their OCD symptoms. A family history screen was used to determine whether participants had a first-degree relative with a history of any of the following specific symptoms: hoarding, contamination/cleaning, symmetry/ordering, doubt/checking and/or other OCD symptoms. The characteristics of participants with a family history of a specific OCD symptom were compared to those of participants with a family history of any other OCD symptom. This was repeated for each specific OCD symptom. The roles of co-occurring tics and age of onset of OCD were also assessed. Distinct familial associations were detected for the symptoms of hoarding and contamination/cleaning. Age of onset of OCD was significantly younger in participants who reported a family history of "other" symptoms. These findings suggest that certain OCD symptom dimensions are more familial than others, which has significant implications for aetiology of OCD.

Psychometric properties of the DY-BOCS in a Turkish sample of children and adolescents

BACKGROUND

Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) is a promising scale for assessing frequency and severity of symptom dimensions. The main objective of the study was to assess the psychometric properties of the DY-BOCS in a large sample of children and adolescents from Turkey.

METHODS

We studied 143 children and adolescents, 7-18years, with well characterized DSM-IV-R OCD, ascertained from seven collaborating university or state hospital sites. We compared the DY-BOCS scores with the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS), the Children's Depression Inventory (CDI), the Yale Global Tic Severity Scale (YGTSS) and the Child Behavior Checklist 6-18years (CBCL 6-18).

RESULTS

The internal consistency of the DY-BOCS symptom dimensions and inter-rater agreement of component scores were excellent. The agreement between global DY-BOCS score and the total CY-BOCS score was highly significant (Pearson's r=0.55, p<0.0001). Severity scores for individual symptom dimensions were independent of one another, only modestly correlating with the global ratings, and were also differentially related to ratings of depression, anxiety and tic severity.

CONCLUSION

The DY-BOCS is a reliable and valid instrument for assessing multiple aspects of OCD symptom severity in children and adolescents from Turkey.

Incompleteness, aesthetic sensitivity, and the obsessive-compulsive need for symmetry

BACKGROUND AND OBJECTIVES

The "need for symmetry" is a well recognized yet little understood feature of obsessive-compulsive (OC) experience. In light of the strong associations between the OC-related trait of incompleteness and symmetry-related behaviors and symptoms, and between perceptual symmetry and aesthetic judgments, this study examined whether trait incompleteness is associated with enhanced natural aesthetic skill and/or aesthetic sensitivity, particularly as they pertain to visual symmetry.

METHODS

A quasi-experimental design was used to compare the responses of nonclinical individuals with high versus average levels of trait incompleteness on self-report measures and two performance measures of aesthetic judgment.

RESULTS

Compared to controls, participants high in incompleteness reported higher levels of self-perceived symmetry-related concerns and behaviors, and displayed greater aesthetic sensitivity in the form of substantially heightened preferences for symmetry in images. Contrary to the hypothesis relating to aesthetic skill, however, the two groups did not differ in their capacity to estimate accurately the objective aesthetic value of images. Nor did they differ in self-reported aesthetics interests and background.

LIMITATIONS

A clinical sample was not included.

CONCLUSIONS

Findings provide evidence that high trait incompleteness is associated not just with symptomatic symmetry-related concerns but with a nonspecific heightened preference for visual symmetry. Conceptual implications are discussed, particularly the potential value of the perceptual fluency theory of symmetry and aesthetic response for explaining the association between incompleteness and symmetry preferences and symptoms.

Symptom Dimensions in Obsessive-Compulsive Disorder and Obsessive Beliefs

BACKGROUND

Obsessive-compulsive disorder (OCD) is a heterogeneous condition with a few major symptom dimensions. These symptom dimensions are thought to have unique clinical and neurobiological correlates. There seems to be a specific relation between OCD symptom dimensions and obsessive beliefs, but the findings are not consistent across studies. There is also a paucity of literature from culturally diverse settings. One of the reasons for the varied findings could be due to the method employed in measuring OCD symptoms.

MATERIALS AND METHODS

In this study, we examined the relation between symptom dimensions and obsessive beliefs using the Dimensional Yale-Brown Obsessive-Compulsive Scale and the Obsessive Beliefs Questionnaire respectively in 75 patients with Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition OCD.

RESULTS

Perfectionism predicted both aggressive and symmetry dimensions whereas responsibility beliefs predicted sexual and religious dimensions.

CONCLUSIONS

The findings suggest that certain obsessive beliefs predicted certain OCD symptom dimensions, but results are not entirely consistent with the published literature suggesting the possibility of cross-cultural variations. That the symptom dimensions have unique belief domains support the argument that symptom dimensions could be targeted to reduce the heterogeneity in etiological and treatment studies of OCD. Therapeutic interventions may have to aim at modifying unique belief domains underlying certain symptom dimensions rather than having generic cognitive-behavioral strategies.

The impact of tics, obsessive-compulsive symptoms, and impulsivity on global functioning in Tourette syndrome

This study investigated the relationships between tics, obsessive-compulsive symptoms (OCS), and impulsivity, and their effects on global functioning in Japanese patients with Tourette syndrome (TS), using the dimensional approach for OCS. Fifty-three TS patients were assessed using the Yale Global Tic Severity Scale, the Dimensional Yale-Brown Obsessive-Compulsive Scale, the Impulsivity Rating Scale, and the Global Assessment of Functioning Scale. Although tic severity scores were significantly and positively correlated with OCS severity scores, impulsivity severity scores were not significantly correlated with either. The global functioning score was significantly and negatively correlated with tic and OCS severity scores. Of the 6 dimensional OCS scores, only aggression scores had a significant negative correlation with global functioning scores. A stepwise multiple regression analysis showed that only OCS severity scores were significantly associated with global functioning scores. Despite a moderate correlation between tic severity and OCS severity, the impact of OCS on global functioning was greater than that of tics. Of the OCS dimensions, only aggression had a significant impact on global functioning. Our findings suggest that it is important to examine OCS using a dimensional approach when analyzing global functioning in TS patients.

Obsessive-compulsive symptom dimensions in a population-based, cross-sectional sample of school-aged children

BACKGROUND

Obsessive-compulsive disorder can be expressed as four potentially overlapping obsessive-compulsive symptom (OCS) dimensions (OCSD) ("symmetry/ordering", "contamination/cleaning", "aggressive/sexual/religious" and "collecting/hoarding"). In clinical samples, some dimensions are more familial and associated with increased psychiatric comorbidity and malfunctioning. However, data concerning OCS and OCSD are scarce in non-clinical samples, particularly among children. The present study aims to estimate: (1) the prevalence and sex/age distribution of OCS/OCSD in a community-based sample of schoolchildren; (2) the association between OCS and additional clinical factors; and (3) the degree of familial aggregation of OCS/OCSD.

METHODS

OCS and OCSD were evaluated in 9937 Brazilian school-children (6-12 years-old) and their biological relatives using the Family History Screen. Data analyses included gradient estimated equations and post-hoc tests.

RESULTS

We included data on 9937 index-children, 3305 siblings (13-18 years-old), and 16,218 parents. Biological mothers were the informants in 87.6% of the interviews. OCS were present in 14.7% of the index-children; 15.6% of their siblings; 34.6% of their mothers and 12.1% of their fathers. The prevalence of OCS and each of the OCSD gradually increased from ages 6 to 12 years. Overall, OCS in children were associated with the presence of other psychiatric symptoms, as well as behavioral/school impairment. OCS and each of the four OCSD aggregated significantly within families.

CONCLUSIONS

OCS are prevalent and associated with psychiatric symptoms and clinical impairment among school-aged children. OCSD aggregate within families in a dimension-specific fashion. These findings suggest a natural continuum between OCS and OCD with regard to their dimensional character.

A personal 35 year perspective on Gilles de la Tourette syndrome: assessment, investigations, and management

After having examined the definition, clinical phenomenology, comorbidity, psychopathology, and phenotypes in the first paper of this Series, here I discuss the assessment, including neuropsychology, and the effects of Gilles de la Tourette syndrome with studies showing that the quality of life of patients with Tourette's syndrome is reduced and that there is a substantial burden on the family. In this paper, I review my local and collaborative studies investigating causal factors (including genetic vulnerability, prenatal and perinatal difficulties, and neuro-immunological factors). I also present my studies on neuro-imaging, electro-encephalograms, and other special investigations, which are helpful in their own right or to exclude other conditions. Finally, I also review our studies on treatment including medications, transcranial magnetic stimulation, biofeedback, target-specific botulinum toxin injections, biofeedback and, in severe refractory adults, psychosurgery and deep brain stimulation. This Review summarises and highlights selected main findings from my clinic (initially The National Hospital for Neurology and Neurosurgery Queen Square and University College London, UK, and, subsequently, at St George's Hospital, London, UK), and several collaborations since 1980. As in Part 1 of this Series, I address the main controversies in the fields and the research of other groups, and I make suggestions for future research.

Comparison of clinical characteristics of familial and sporadic obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is a heterogeneous condition with evidence of familiality in a considerable proportion of patients. A classification into familial and sporadic forms has been proposed to explain the heterogeneity. The current study aims to compare the demographic, clinical and comorbidity patterns of patients with and without a family history of OCD in first-degree relatives.

METHOD

802 consecutive patients who consulted a specialty OCD Clinic at a tertiary care psychiatric hospital in India were evaluated with the Mini-International Neuropsychiatric Interview, the Yale-Brown Obsessive-Compulsive Scale, and the Clinical Global Impression Scale. Family history was assessed by interviewing patients and at least one first-degree relative.

RESULTS

Family history of OCD was seen in 152 patients (19%). Family history was associated with juvenile onset (Χ(2)=19.472, p<0.001), obsessions of contamination (Χ(2)=6.658, p=0.01), hoarding (Χ(2)=4.062, p=0.032), need for symmetry (Χ(2)=3.95, p=0.047), washing compulsion (Χ(2)=7.923, p=0.005), ordering compulsions (Χ(2)=6.808, p=0.009), repeating compulsions (Χ(2)=4.950, p=0.026) and compulsions by proxy (Χ(2)=7.963, p=0.005). Family history was also associated with greater severity of OCD (t=-2.31, p=0.022) and compulsions (t=-3.09, p=0.002) and longer duration of illness at presentation (t=-2.93, p=0.004).

CONCLUSION

Our findings suggest that familial OCD may have distinctive clinical features. Studying familial forms of OCD may offer unique insight in to understanding the genetic basis of OCD.

A Bifactor Model of Disgust Proneness

The current research evaluated a bifactor model for the Disgust Emotion Scale (DES) in three samples: N = 1,318 nonclinical participants, N = 152 clinic-referred patients, and N = 352 nonclinical participants. The primary goals were to (a) use bifactor modeling to examine the latent structure of the DES and in turn (b) evaluate whether the DES should be scored as a unidimensional scale or whether subscales should also be interpreted. Results suggested that a bifactor model fit the DES data well and that all DES items were strongly influenced by a general disgust proneness dimension and by five content dimensions. Moreover, model-based reliability analyses suggested that scoring a general disgust dimension is justified despite the confirmed multidimensional structure. However, subscales were found to be unreliable after controlling for the general disgust factor with the potential exception of the Mutilation/Death and Animals subscale. Subsequent analysis also showed that only the general disgust factor robustly predicted an obsessive-compulsive disorder symptom latent factor—a clinical condition closely related to disgust proneness; latent variables representing DES domains displayed weak relations with an obsessive-compulsive disorder factor above and beyond the general disgust factor. Implications for better understanding the structure of DES responses and its use in clinical research are discussed.

Relationship between early maladaptive schemas and symptom dimensions in patients with obsessive-compulsive disorder

The aims of this study were to evaluate early maladaptive schemas (EMSs) of patients with obsessive-compulsive disorder (OCD) and to clarify relationships between particular EMSs and the five factor-analyzed symptom dimensions and other clinical variables. Fifty-seven patients with OCD and 70 normal controls completed the Young Schema Questionnaire, the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), the Y-BOCS symptom checklist, and the Beck Depression Inventory. Patients with OCD had significantly higher scores for schema related to defectiveness/shame, social isolation/alienation, and failure than did normal controls. Among the five OCD symptom dimensions, the sexual/religious dimension was only significantly correlated with two schemas of vulnerability to harm or illness and enmeshment/undeveloped self. These two schemas were significant predictors of the sexual/religious dimension, accounting for 33% of the total variance in this dimension. Any EMSs in patients with OCD were not related to clinical variables such as severity of OCD and duration of illness. These findings may constitute evidence to improve our understandings of OCD from a perspective of schema theory.

Development and validation of a computer-based measure of symmetry and arranging behavior in obsessive-compulsive disorder: a preliminary study

OBJECTIVE

While compulsive ordering and arranging, and a preoccupation with symmetry are common presentations of obsessive-compulsive disorder (OCD), little attention has been given to these types of symptoms in the assessment of patients with OCD. The goal of the present study was to develop and evaluate psychometric properties for the objective and quantitative measurement of compulsive symptoms related to symmetry and arranging.

METHODS

Thirty-five normal volunteers performed computer-simulated environment tasks under four different conditions with or without a target and distraction. Primary dependent variables included several indices of time and manipulation of arranging behaviors. We evaluated the validity of the task by comparing the novel behavioral measures with standardized measures such as the Symmetry, Ordering and Arranging Questionnaire (SOAQ), Obsessive Compulsive Inventory-Revised (OCI-R), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Barratt Impulsiveness Scale (BIS-11), and Quality of Life Scale (WHOQOL).

RESULTS

We found a significant positive correlation between the arrangement time (time to complete the task) with the SOAQ score and the "ordering" subscore of the OCI-R. In addition, the number of manipulations was positively correlated with the SOAQ score and the "ordering" subscore of the OCI-R. There were no significant correlations between behavioral parameters and other scales measuring constructs less relevant to the symptoms of OCD related to ordering/symmetry. There was only a significant main effect of the target on the arrangement time.

CONCLUSION

This study demonstrates the good convergent and discriminant validity of this task as a novel behavioral measure for the assessment of arranging compulsion symptoms. We can infer from the results that subjects are likely to spend more time in compulsive arranging when the target for the task is given.

Genome-wide sequencing for the identification of rearrangements associated with Tourette syndrome and obsessive-compulsive disorder

Background

Tourette Syndrome (TS) is a neuropsychiatric disorder in children characterized by motor and verbal tics. Although several genes have been suggested in the etiology of TS, the genetic mechanisms remain poorly understood.

Methods

Using cytogenetics and FISH analysis, we identified an apparently balanced t(6,22)(q16.2;p13) in a male patient with TS and obsessive-compulsive disorder (OCD). In order to map the breakpoints and to identify additional submicroscopic rearrangements, we performed whole genome mate-pair sequencing and CGH-array analysis on DNA from the proband.

Results

Sequence and CGH array analysis revealed a 400 kb deletion located 1.3 Mb telomeric of the chromosome 6q breakpoint, which has not been reported in controls. The deletion affects three genes (GPR63, NDUFA4 and KLHL32) and overlaps a region previously found deleted in a girl with autistic features and speech delay. The proband’s mother, also a carrier of the translocation, was diagnosed with OCD and shares the deletion. We also describe a further potentially related rearrangement which, while unmapped in Homo sapiens, was consistent with the chimpanzee genome.

Conclusions

We conclude that genome-wide sequencing at relatively low resolution can be used for the identification of submicroscopic rearrangements. We also show that large rearrangements may escape detection using standard analysis of whole genome sequencing data. Our findings further provide a candidate region for TS and OCD on chromosome 6q16.

Delayed bedtimes and obsessive-compulsive symptoms

There is increasing recognition of an important interplay between psychiatric disorders and sleep. Clinical observations and several empirical studies have shown that later bedtimes are associated with obsessive-compulsive disorder (OCD). This study examined the relation of delayed bedtimes (DBs) and symptoms of OCD. Two hundred and sixty-six undergraduates completed a battery of questionnaires assessing sleep patterns, mood, and obsessive-compulsive (OC) symptoms. Results showed that participants with DBs reported increased rates of OC symptoms, as compared with non-DB participants. Further, this relation remained significant when controlling for negative affect. Additional work examining the interplay between sleep and OC symptoms is warranted.

Association between the NMDA glutamate receptor GRIN2B gene and obsessive-compulsive disorder

BACKGROUND

Recent data from neuroimaging, genetic and clinical trials and animal models suggest a role for altered glutamatergic neuro transmission in the pathogenesis of obsessive-compulsive disorder (OCD). The aim of this study was to investigate whether variants in the GRIN2B gene, the gene encoding the NR2 subunit of the N-methyl-D-aspartate (NMDA) glutamate receptor, may contribute to genetic susceptibility to OCD or to different OCD subphenotypes.

METHODS

Between 2003 and 2008, we performed a case-control association study in which we genotyped 10 tag single-nucleotide polymorphisms (SNPs) in the 3' untranslated region (3' UTR) of GRIN2B. We performed SNP association and haplotype analysis considering the OCD diagnosis and different OCD subphenotypes: early-onset OCD, comorbid tic disorders and OCD clinical symptom dimensions.

RESULTS

We enrolled 225 patients with OCD and 279 controls recruited from the OCD Clinic at Bellvitge Hospital (Barcelona, Spain). No significant difference in the distribution of alleles or genotypes was detected between patients with OCD and controls. Nonetheless, on analyzing OCD subphenotypes, the rs1805476 SNP in male patients (95% confidence interval [CI] 1.37-4.22, p = 0.002) and a 4-SNP haplotype in the whole sample (rs1805476, rs1805501, rs1805502 and rs1805477; odds ratio 1.92, 95% CI 1.22-3.01; permutation p = 0.023) were significantly associated with the presence of contamination obsessions and cleaning compulsions.

LIMITATIONS

Study limitations included the risk of population stratification associated with the case-control design, use of psychiatrically unscreened blood donors as the control group, reduced sample size of participants with certain OCD subphenotypes and tested polymorphisms limited to 3' UTR and exon 13 of GRIN2B.

CONCLUSION

Our results converge with recent data suggesting a possible contribution of glutamatergic variants to the genetic vulnerability to OCD or at least to certain OCD manifestations. The dissection of OCD into more homogeneous subphenotypes may constitute a useful tool to disentangle the complex genetic basis of the disorder.

Clinical features of obsessive-compulsive disorder with hoarding symptoms: a multicenter study

BACKGROUND

Factor analyses indicate that hoarding symptoms constitute a distinctive dimension of obsessive-compulsive disorder (OCD), usually associated with higher severity and limited insight. The aim was to compare demographic and clinical features of OCD patients with and without hoarding symptoms.

METHOD

A cross sectional study was conducted with 1001 DSM-IV OCD patients from the Brazilian Research Consortium of Obsessive-Compulsive Spectrum Disorders (CTOC), using several instruments. The presence and severity of hoarding symptoms were determined using the Dimensional Yale-Brown Obsessive-Compulsive Scale. Statistical univariate analyses comparing factors possibly associated with hoarding symptoms were conducted, followed by logistic regression to adjust the results for possible confounders.

RESULTS

Approximately half of the sample (52.7%, n = 528) presented hoarding symptoms, but only four patients presented solely the hoarding dimension. Hoarding was the least severe dimension in the total sample (mean score: 3.89). The most common lifetime hoarding symptom was the obsessive thought of needing to collect and keep things for the future (44.0%, n = 440). After logistic regression, the following variables remained independently associated with hoarding symptoms: being older, living alone, earlier age of symptoms onset, insidious onset of obsessions, higher anxiety scores, poorer insight and higher frequency of the symmetry-ordering symptom dimension. Concerning comorbidities, major depressive, posttraumatic stress and attention deficit/hyperactivity disorders, compulsive buying and tic disorders remained associated with the hoarding dimension.

CONCLUSION

OCD hoarding patients are more likely to present certain clinical features, but further studies are needed to determine whether OCD patients with hoarding symptoms constitute an etiologically discrete subgroup.

The nature, assessment, and treatment of obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is an anxiety disorder that affects between 1% to 2% of individuals and causes considerable impairment and disability. Although > 50% of individuals experience symptom onset in childhood, symptoms can continue to develop throughout adulthood. Accurate and timely assessment of clinical presentation is critical to limit impairment and improve prognosis. Presently, there are 2 empirically supported treatments available for OCD in children and adults, namely cognitive-behavioral therapy and pharmacotherapy with serotonin reuptake inhibitors. This article provides an introduction to the phenomenology, etiology, and clinical course of OCD. Assessment practices used to evaluate symptom severity are described, and evidence-based treatment options are reviewed, with appropriate distinctions drawn between children and adults. Finally, recommendations for assessment and treatment practices for OCD are explicated.

Impact of obsessive-compulsive symptoms in Tourette's syndrome on neuropsychological performance

AIM

Although inconsistencies in neuropsychological impairments in Tourette's syndrome (TS) have been discussed with respect to comorbid disorders, such as obsessive-compulsive disorder, few studies have focused on the specific dimensions of obsessive-compulsive symptoms (OCS) related to TS, such as aggression and symmetry. The aim of this study was to explore the impact of specific TS-related OCS on neuropsychological performance.

METHODS

A series of neuropsychological tasks examining attention and executive functioning were performed in groups of 33 TS participants and 18 healthy controls. The neuropsychological performance of TS with Aggression OCS (n = 11) were compared to TS without Aggression OCS (n = 22) and controls by using MANCOVA controlling for age. In the same way as Aggression, we compared the performance of three groups by Symmetry: TS with Symmetry OCS (n = 14), TS without Symmetry OCS (n = 19) and controls.

RESULTS

TS participants with Aggression OCS tended to make more perseverative errors than those without. Global OCS severity and tic severity did not correlate with any neuropsychological performances. No significant differences were detected between TS participants with and without Symmetry OCS.

CONCLUSION

Neuropsychological deficits in TS might be affected not by global OCS severity but by specific TS-related OCS.

Translational approaches to obsessive-compulsive disorder: from animal models to clinical treatment

Obsessive-compulsive disorder (OCD) is characterized by obsessions (intrusive thoughts) and compulsions (repetitive ritualistic behaviours) leading to functional impairment. Accumulating evidence links these conditions with underlying dysregulation of fronto-striatal circuitry and monoamine systems. These abnormalities represent key targets for existing and novel treatment interventions. However, the brain bases of these conditions and treatment mechanisms are still not fully elucidated. Animal models simulating the behavioural and clinical manifestations of the disorder show great potential for augmenting our understanding of the pathophysiology and treatment of OCD. This paper provides an overview of what is known about OCD from several perspectives. We begin by describing the clinical features of OCD and the criteria used to assess the validity of animal models of symptomatology; namely, face validity (phenomenological similarity between inducing conditions and specific symptoms of the human phenomenon), predictive validity (similarity in response to treatment) and construct validity (similarity in underlying physiological or psychological mechanisms). We then survey animal models of OC spectrum conditions within this framework, focusing on (i) ethological models; (ii) genetic and pharmacological models; and (iii) neurobehavioural models. We also discuss their advantages and shortcomings in relation to their capacity to identify potentially efficacious new compounds. It is of interest that there has been rather little evidence of 'false alarms' for therapeutic drug effects in OCD models which actually fail in the clinic. While it is more difficult to model obsessive cognition than compulsive behaviour in experimental animals, it is feasible to infer cognitive inflexibility in certain animal paradigms. Finally, key future neurobiological and treatment research areas are highlighted.

Risk factors prospectively associated with adult obsessive-compulsive symptom dimensions and obsessive-compulsive disorder

BACKGROUND

Very few longitudinal studies have evaluated prospective neurodevelopmental and psychosocial risk factors for obsessive-compulsive disorder (OCD). Furthermore, despite the heterogeneous nature of OCD, no research has examined risk factors for its primary symptom dimensions, such as contamination/washing.

METHOD

Potential risk factors for symptoms or diagnosis of OCD in adulthood and for specific adult obsessive-compulsive (OC) symptom dimensions were examined in the Dunedin Study birth cohort. The presence of obsessions and compulsions and psychological disorders was assessed using the Diagnostic Interview Schedule (DIS) at ages 26 and 32 years. Individuals with a diagnosis of OCD at either age (n=36) were compared to both a healthy control group (n=613) and an anxious control group (n=310) to determine whether associations between a risk factor and an OCD diagnosis were specific.

RESULTS

Childhood neurodevelopmental, behavioral, personality and environmental risk factors were associated with a diagnosis of OCD and with OC symptoms at ages 26 and 32. Social isolation, retrospectively reported physical abuse and negative emotionality were specific predictors of an adult OCD diagnosis. Of note, most risk factors were associated with OC symptoms in adulthood and several risk factors predicted specific OCD dimensions. Perinatal insults were linked to increased risk for symmetry/ordering and shameful thoughts dimensions, whereas poor childhood motor skills predicted the harm/checking dimension. Difficult temperament, internalizing symptoms and conduct problems in childhood also predicted specific symptom dimensions and lower IQ non-specifically predicted increased risk for most dimensions.

CONCLUSIONS

The current findings underscore the need for a dimensional approach in evaluating childhood risk factors for obsessions and compulsions.

Functional neuroimaging in obsessive-compulsive disorder

BACKGROUND AND AIM

Obsessive-compulsive disorder (OCD) is a severe, highly prevalent and chronically disabling psychiatric disorder that usually emerges during childhood or adolescence. This paper aims to review the literature on functional neuroimaging in OCD, analysing the reported dysfunctional connectivity in the corticostriatothalamocortical circuitry.

METHOD

This study included papers published in peer-reviewed journals dealing with functional imaging in OCD.

RESULTS

Striatal dysfunction, mainly of the caudate nucleus, leads to inefficient thalamic gating, resulting in hyperactivity within the orbitofrontal cortex (intrusive thoughts) and the anterior cingulate cortex (non-specific anxiety). Compulsions consist of ritualistic behaviours performed to recruit the inefficient striatum and neutralise unwanted thoughts and anxiety. Functional neuroimaging findings are discussed against the background of specific cognitive impairments, mainly regarding visuospatial processing, executive functioning and motor speed. Cognitive deficits are partial and specific, matching imaging data.

CONCLUSIONS

Several studies have targeted brain regions hypothesised to be involved in the pathogenesis of OCD, showing the existence of dysfunctional connectivity in the corticostriatothalamocortical circuitry. Improvements in spatial resolution of neuroimaging techniques may contribute to a better understanding of the neurocircuitry of OCD and other anxiety disorders.

Obsessive-compulsive disorder in children and adolescents: symptom dimensions in a naturalistic setting

BACKGROUND

Obsessive-compulsive disorder (OCD) is a frequent and clinically heterogeneous disorder. The complex clinical presentation can be summarized using a few consistent and temporally stable symptom dimensions. Only few studies in children and adolescents have examined the importance of symptom dimensions.

AIMS

This retrospective study was undertaken to describe the relation between symptom dimensions, pattern of comorbidity and family disposition, in a sample of Danish children and adolescents with OCD assessed in a naturalistic setting.

METHODS

A retrospective study of children and adolescents (n=83) diagnosed with OCD in the period 1998-2004, at the Psychiatric Hospital for Children and Adolescents, Risskov, Denmark. Information from clinical records was systematically collected and Children's Yale-Brown Obsessive-compulsive Scale (CY-BOCS) scores and symptom checklists were obtained.

RESULTS

High scores on the symmetry/ordering dimension were related to OCD in first-degree relatives and high scores on the aggressive/checking dimension were associated to comorbidity with tic disorders. We showed a correlation between limited insight and younger age.

CONCLUSION

This is one of the first studies to examine symptom dimensions in children and adolescents in naturalistic settings. The results were comparable with those in adult studies, showing an association between the occurrence of the symmetry/ordering dimension and family OCD and the occurrence of the aggressive/checking dimension and comorbid tic disorders. In small children, insight into symptoms may be limited.

Recent advances in Tourette syndrome

PURPOSE OF REVIEW

This review considers the recent literature pertaining to the neurobiology, genetics and treatment of Tourette syndrome.

RECENT FINDINGS

Over the last several years, both neuropathological and genetic findings have further focused attention on long-standing hypotheses regarding the role of the basal ganglia in causing tics and Tourette syndrome. Moreover, although the field awaits the results the first large-scale genetic studies, recent findings have already mirrored developments in the neuropsychiatric genetics literature more broadly, highlighting the value of the study of rare variation and the overlap of risks among seemingly disparate diagnostic categories. Finally, treatment studies have underscored the importance of cognitive-behavioral as well as pharmacological interventions for the treatment of tic disorders.

SUMMARY

Recent findings have led to novel, testable hypotheses regarding the molecular and cellular mechanisms underlying Tourette syndrome. These, in turn, have begun to provide new avenues to conceptualizing treatment strategies. Although the development of additional medication options is a pressing need, recent data has demonstrated both the safety and efficacy of nonpharmacological approaches.

Variants in estrogen receptor alpha gene are associated with phenotypical expression of obsessive-compulsive disorder

Compelling data from animal and clinical studies suggest that sex steroids may play a role in the etiopathology of obsessive-compulsive disorder (OCD). The aim of this study was to investigate whether variants in estrogen receptor genes ESR1 and ESR2 may contribute to the genetic susceptibility to OCD, through a case-control association study using an extensive linkage disequilibrium-mapping approach. Twenty tag single-nucleotide polymorphisms (tagSNPs) covering the ESR2 region and nine tagSNPS from regions of ESR1 reported to be related to transcriptional control were genotyped in 229 OCD patients and 279 controls. SNP association and haplotype analysis were performed. The association of these genes and OCD subphenotypes was tested, considering early-onset OCD, comorbid tic and affective disorders, and OCD symptom dimensions. No significant difference in the distribution of alleles or genotypes was detected between controls and OCD subjects. Nevertheless, on analyzing OCD subphenotypes, SNP rs34535804 in ESR1 and a five SNPs haplotype, located at the 5' end of intron 1 of ESR1, were associated with the presence of contamination obsessions and cleaning compulsions. Specifically, carriers of the ACCCG haplotype, a combination of functional alleles related to higher ER alpha expression, showed a reduced risk of suffering from these symptoms. Our results suggest that the ESR1 gene may contribute to the genetic vulnerability to certain OCD manifestations. The dissection of OCD into more homogeneous subphenotypes may well help to identify susceptibility genes for the disorder.

Suicide in patients treated for obsessive-compulsive disorder: a prospective follow-up study

BACKGROUND

To describe the occurrence of persistent suicidal ideation and suicide attempts in a sample of obsessive-compulsive patients followed-up prospectively during 1 to 6years, and to determine the existence of predictors of suicide behavior.

METHOD

Two hundred and eighteen outpatients with DSM-IV OCD, recruited from a specialized OCD Unit in Barcelona, Spain, between February 1998 and December 2007, were included in the study. Suicide ideation was assessed by item 3 of the Hamilton Depression Rating Scale. Suicide attempts were evaluated by the Beck Suicide Intent Scale. Patients with and without persistent suicidal thoughts and suicide attempters and non-attempters were compared on sociodemographic and clinical variables. A Cox proportional hazards regression analysis was used to estimate potential predictors of suicide.

RESULTS

Patients completed a mean follow-up period of treatment of 4.1years (SD: 1.7; range: 1-6years). During this period, eighteen patients (8.2%) reported persistent suicidal ideation, two patients (0.91%) committed suicide and 11 (5.0%) attempted suicide. Being unmarried, presenting higher basal scores in the HDRS, current or previous history of affective disorders and symmetry/ordering obsessions were independently associated with suicidal behaviors.

LIMITATIONS

Patients were recruited from a specialized OCD clinic and received exhaustive treatment. Influence of variables including social support, life events, hopelessness and substance abuse/dependence was not assessed.

CONCLUSIONS

Suicide behavior is not a highly common phenomenon in OCD, but it should not be disregarded, especially in unmarried patients, with comorbid depression and symmetry/ordering obsessions and compulsions, who appear to be at a greater risk for suicide acts.

Obsessive-compulsive disorder: a review of the diagnostic criteria and possible subtypes and dimensional specifiers for DSM-V

BACKGROUND

Since the publication of the DSM-IV in 1994, research on obsessive-compulsive disorder (OCD) has continued to expand. It is timely to reconsider the nosology of this disorder, assessing whether changes to diagnostic criteria as well as subtypes and specifiers may improve diagnostic validity and clinical utility.

METHODS

The existing criteria were evaluated. Key issues were identified. Electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies.

RESULTS

This review presents a number of options and preliminary recommendations to be considered for DSM-V. These include: (1) clarifying and simplifying the definition of obsessions and compulsions (criterion A); (2) possibly deleting the requirement that people recognize that their obsessions or compulsions are excessive or unreasonable (criterion B); (3) rethinking the clinical significance criterion (criterion C) and, in the interim, possibly adjusting what is considered "time-consuming" for OCD; (4) listing additional disorders to help with the differential diagnosis (criterion D); (5) rethinking the medical exclusion criterion (criterion E) and clarifying what is meant by a "general medical condition"; (6) revising the specifiers (i.e., clarifying that OCD can involve a range of insight, in addition to "poor insight," and adding "tic-related OCD"); and (7) highlighting in the DSM-V text important clinical features of OCD that are not currently mentioned in the criteria (e.g., the major symptom dimensions).

CONCLUSIONS

A number of changes to the existing diagnostic criteria for OCD are proposed. These proposed criteria may change as the DSM-V process progresses.

Obsessive-compulsive symptom dimensions in Japanese tourette syndrome subjects

OBJECTIVES

To investigate the current and lifetime frequency and severity of obsessive-compulsive (OC) symptom dimensions in Tourette syndrome (TS) patients, and how these dimensions affect clinical characteristics.

METHODS

Forty TS outpatients (29 males, 11 females) were interviewed with the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS), the Yale Global Tic Severity Scale (YGTSS), the Shapiro Tourette Syndrome Severity Scale, and the Global Assessment of Functioning (GAF).

RESULTS

OC symptoms were present in 80% of the total sample. The miscellaneous and the symmetry dimensions were the most frequent at the "current" and "lifetime" surveys, respectively. The aggression dimension had the smallest difference between "worst ever" and current ratings among the all OC symptom dimensions. TS patients with the aggression dimension (n=7) had significantly lower scores in the GAF scale and higher frequencies of coprolalia. There were significant correlations between the YGTSS severity scores and specific DY-BOCS dimensions.

CONCLUSION

OC symptoms are frequent in TS subjects and there were differences in the frequency, severity, and course of the OC symptom dimensions. These results emphasize the need for future longitudinal studies using a dimensional approach for the evaluation of OC symptoms in tic disorders.

Dimensional predictors of response to SRI pharmacotherapy in obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is clinically heterogeneous. Previous studies have reported different patterns of treatment response to serotonin reuptake inhibitors (SRI) based on symptom dimension. Our objective was to replicate these results in OCD patients who participated in one of four randomized, placebo-controlled, clinical trials (RCT).

METHODS

A total of 165 adult OCD subjects participated in one or more eight-week RCT with clomipramine, fluvoxamine, or fluoxetine. All subjects were classified as having major or minor symptoms in four specific OC symptom dimensions that were derived in a previous factor analytic study involving many of these same patients. Ordinal logistic regression was used to test the association between OC symptom dimensions and SRI response.

RESULTS

We found a significant association between the symptom dimension involving sexual, religious and harm-related obsessions as well as checking compulsions (AGG/SR) and improved SRI response. This increased rate of SRI response was experienced primarily by individuals with harm-related obsessions. Over 60% of patients with AGG/SR OCD symptoms were rated as very much improved after SRI treatment.

LIMITATIONS

As some of the RCTs included were conducted prior to the development of the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), improvement in OCD severity was assessed using the Clinical Global Improvement (CGI) Scale. Data from the double-blind and open-label continuation phases of these trials was collapsed together to increase statistical power.

CONCLUSIONS

Patients with OCD vary in their response to SRIs. The presence of AGG/SR symptoms is associated with an initial positive response to SRIs. These data add to the growing body of work linking central serotonin systems with aggressive behavior.

Are obsessive-compulsive symptom dimensions familial in nonclinical individuals?

BACKGROUND

Obsessive-compulsive disorder (OCD) is a heterogeneous condition, which can be expressed as various potentially overlapping symptom dimensions. In clinical samples, some of these dimensions are associated with increased familial risk for OCD and appear to be familial (intercorrelated within pairs of affected family members), whereas others are not. The goal of this study was to determine whether obsessive-compulsive (OC) symptom dimensions are familial in a nonclinical sample.

METHODS

OC symptom dimensions and negative affect were assessed in 184 female undergraduate students and their parents using the Obsessive-Compulsive Inventory-Revised (OCI-R) and the Positive and Negative Affect Scales, respectively. Bivariate correlations and multiple regression models controlling for age and negative affect were employed to examine the familiarity of OC symptom dimensions.

RESULTS

The OCI-R total scores were significantly correlated in both mother-daughter and father-daughter dyads but the magnitude of these correlations tended to be greater for the mother-daughter dyads. Multiple regression models showed that the Ordering and Hoarding subscales of the OCI-R breed true in mother-daughter dyads. Ordering scores in mothers were also predictive of other symptoms in the daughters (Washing and Checking).

CONCLUSIONS

These results are broadly consistent with the findings in clinical samples and suggest that Ordering and Hoarding are more strongly familial than other symptom dimensions and that high Ordering scores in mothers are associated with increased levels of symptoms in daughters in a less specific manner.

The role of the brain-derived neurotrophic factor (BDNF) val66met variant in the phenotypic expression of obsessive-compulsive disorder (OCD)

Evidence suggests that the Val66Met variant of the brain-derived neurotrophic factor (BDNF) gene may play a role in the etiology of Obsessive-Compulsive Disorder (OCD). In this study, the role of the BDNF Val66Met variant in the etiology and the phenotypic expression of OCD is investigated. Associations between the BDNF Val66Met variant and OCD, obsessive-compulsive symptom dimensions, Yale-Brown Obsessive Compulsive Scale (YBOCS) severity scores, age of onset and family history of obsessive-compulsive symptoms were assessed. The BDNF Val66Met variant was genotyped in 419 patients with sub-/clinical OCD and 650 controls. No differences in allele or genotype frequency were observed between cases and controls. In females with OCD, the Met66Met genotype was associated with later age of onset and a trend for a negative family history, whereas the Val66Val genotype was associated with a trend for lower YBOCS severity scores. Item-level factor analysis revealed six factors: 1) Contamination/cleaning; 2) Aggressive obsessions/checking; 3) Symmetry obsessions, counting, ordering and repeating; 4) Sexual/religious obsessions; 5) Hoarding and 6) Somatic obsessions/checking. A trend was found for a positive association between Factor 4 (Sexual/religious obsessions) and the BDNF Val66Val genotype. The results suggest that BDNF function may be implicated in the mediation of OCD. We found that for the BDNF Met66Met genotype may be associated with a milder phenotype in females and a possible role for the BDNF Val66Val genotype and the BDNF Val66 allele in the sexual/religious obsessions.

Incremental specificity of disgust sensitivity in the prediction of obsessive-compulsive disorder symptoms: Cross-sectional and prospective approaches

The present study examines the association between disgust sensitivity (DS) and obsessive-compulsive disorder (OCD) symptoms in two non-clinical samples. Findings from Study 1 (n=270) revealed a significant association between DS and OCD symptoms even after controlling for negative affect and anxiety sensitivity. Subsequent analysis also revealed a specific association between DS and the washing subtype of OCD symptoms when controlling for other OCD symptom dimensions. DS did not significantly predict residual change in total symptoms of OCD over a 12-week period (n=300) when controlling for risk factors for anxiety disorder symptoms in general (e.g., negative affect, anxiety sensitivity) and OCD specifically (e.g., obsessive beliefs) in Study 2. However, exploratory analyses suggest that DS may be predictive of residual change in some OCD symptom subtypes but not others. Implications of these findings for future research on the role of disgust in OCD are discussed.

Anxiety in boys with attention-deficit/hyperactivity disorder with and without chronic multiple tic disorder

OBJECTIVE

This study examined the psychosocial and behavioral concomitants of anxiety in clinic-referred boys with attention-deficit/hyperactivity disorder (ADHD) with and without chronic multiple tic disorder (CMTD).

METHOD

ADHD boys with (n = 65) and without (n = 94) CMTD were evaluated with measures of psychiatric symptoms, mental health risk factors, and academic and social performance.

RESULTS

Boys with CMTD evidenced more severe anxiety and less social competence and were more likely to be living with only one biological parent than the ADHD Only group, but the magnitude of group differences was generally small. The severity of generalized anxiety, separation anxiety, social phobia, and obsessive-compulsive symptoms were uniquely associated with a different pattern of risk factors, and there was some evidence that these patterns differed for the two groups of boys.

CONCLUSION

Boys with CMTD had a relatively more severe and complex pattern of anxiety that was associated with different clinical features, all of which suggests that ADHD plus CMTD might better be conceptualized as a distinct clinical entity from ADHD Only. However, findings from the extant literature are mixed, and therefore this remains a topic for further study.

The relationship between impulse-control disorders and obsessive-compulsive disorder: a current understanding and future research directions

Impulse-control disorders (ICDs) constitute a heterogeneous group of conditions linked diagnostically by difficulties in resisting "the impulse, drive, or temptation to perform an act that is harmful to the person or to others." Specific ICDs share clinical, phenomenological and biological features with obsessive-compulsive disorder (OCD) that have suggested that these disorders might be categorized together. However, other data suggest significant differences between OCD and ICDs. In this article, clinical, phenomenological and biological features of the formal ICDs are reviewed and compared and contrasted with those of OCD. Available data indicate substantial differences between ICDs and OCD that suggest independent categorizations. Existing research gaps are identified and avenues for future research suggested.

Cross-species models of OCD spectrum disorders

Several axis-I neuropsychiatric disorders are characterised by repetitive motor habits suggestive of underlying inhibitory dyscontrol, and may constitute members of a putative obsessive-compulsive (OC) spectrum. Notable examples include obsessive-compulsive disorder (OCD) and trichotillomania (repetitive hair-pulling). Multiple tiers of evidence link these conditions with underlying dysregulation of fronto-striatal circuitry and monoamine systems. These abnormalities represent key targets for existing and novel treatment interventions. Nonetheless, the brain bases of these conditions, and treatment mechanisms, remain poorly characterised. Animal models of repetitive habits and inhibitory control problems show great potential for augmenting our understanding of the pathophysiology and treatment of OC spectrum conditions. Here, we begin by describing clinical features of OC spectrum disorders, and criteria used to assess the validity of animal models of symptomatology. Namely, face validity (phenomenological similarity between inducing conditions and specific symptoms of the human phenomenon), predictive validity (similarity in response to treatment) and construct validity (similarity in underlying physiological or psychological mechanisms). We then survey animal models of OC spectrum conditions within this framework, focusing on (i) ethological models; (ii) genetic and pharmacological models; and (iii) behavioral models. Key future research directions are highlighted.

Tourette's syndrome, trichotillomania, and obsessive-compulsive disorder: how closely are they related?

The question of whether Tourette's syndrome (TS) and trichotillomania (TTM) are best conceptualized as obsessive-compulsive spectrum disorders was raised by family studies demonstrating a close relationship between TS and obsessive-compulsive disorder (OCD), and by psychopharmacological research indicating that both TTM and OCD respond more robustly to clomipramine than to desipramine. A range of studies have subsequently allowed comparison of the phenomenology, psychobiology, and management of TS and TTM, with that of OCD. Here we briefly review this literature. The data indicate that there is significant psychobiological overlap between TS and OCD, supporting the idea that TS can be conceptualized as an OCD spectrum disorder. TTM and OCD have only partial overlap in their phenomenology and psychobiology, but there are a number of reasons for why it may be useful to classify TTM and other habit disorders as part of the obsessive-compulsive spectrum of disorders.

Overview of genetics and obsessive-compulsive disorder

This paper reviews the current state of research into the genetics of obsessive-compulsive disorder (OCD). Heredity has a major role in OCD etiology. This evidence comes from several methodological approaches such as family, twin, and segregation analysis studies. A major single gene effect as well as a polygenic hypothesis has been suggested based on segregation studies. In addition, candidate gene association and linkage analyses have shown not only one gene, but a few interesting genes and areas of the genome that may be relevant in OCD. In this search for genes, new definitions of the OCD phenotype have emerged, and some of them may be considered intermediate phenotypes between the gene effect and OCD-DSM-IV diagnosis. The phenotypic and genetic heterogeneity of OCD magnifies the challenge of locating susceptibility genes; at the same time, the identification of vulnerability genes will elucidate the identification of subtypes or dimensions of the disorder. Therefore research strategies that take advantage of clinical subtyping and that redefine the OCD phenotype in the context of genetic studies may potentially contribute to the nosology of OCD and ultimately pathophysiology. There is a lack of understanding about how genes and environment interact in OCD. However, there are some reports that will be discussed, which have attempted to evaluate how the environment contributes to OCD.

Obsessive-compulsive disorder: subclassification based on co-morbidity

BACKGROUND

Obsessive-compulsive disorder (OCD) is probably an etiologically heterogeneous condition. Many patients manifest other psychiatric syndromes. This study investigated the relationship between OCD and co-morbid conditions to identify subtypes.

METHOD

Seven hundred and six individuals with OCD were assessed in the OCD Collaborative Genetics Study (OCGS). Multi-level latent class analysis was conducted based on the presence of eight co-morbid psychiatric conditions [generalized anxiety disorder (GAD), major depression, panic disorder (PD), separation anxiety disorder (SAD), tics, mania, somatization disorders (Som) and grooming disorders (GrD)]. The relationship of the derived classes to specific clinical characteristics was investigated.

RESULTS

Two and three classes of OCD syndromes emerge from the analyses. The two-class solution describes lesser and greater co-morbidity classes and the more descriptive three-class solution is characterized by: (1) an OCD simplex class, in which major depressive disorder (MDD) is the most frequent additional disorder; (2) an OCD co-morbid tic-related class, in which tics are prominent and affective syndromes are considerably rarer; and (3) an OCD co-morbid affective-related class in which PD and affective syndromes are highly represented. The OCD co-morbid tic-related class is predominantly male and characterized by high conscientiousness. The OCD co-morbid affective-related class is predominantly female, has a young age at onset, obsessive-compulsive personality disorder (OCPD) features, high scores on the 'taboo' factor of OCD symptoms, and low conscientiousness.

CONCLUSIONS

OCD can be classified into three classes based on co-morbidity. Membership within a class is differentially associated with other clinical characteristics. These classes, if replicated, should have important implications for research and clinical endeavors.

Symptom dimensions and subtypes of obsessive-compulsive disorder: a developmental perspective

In the absence of definitive etiological markers for obsessive-compulsive disorder (OCD% obsessive-compulsive (OC) symptom dimensions may offer a fruitful point of orientation. These dimensions can be understood as defining potentially overlapping clinical features that may be continuous with "normal" worries first evident in childhood. Although the understanding of the dimensional structure of OC symptoms is still imperfect, a recent large-scale meta-analysis has confirmed the presence of at least four separa ble symptom dimensions in children, as well as adults, with OCD. A dimensional approach does not exclude other methods to parse OCD. Thus far, a pediatric age of onset, the presence of other family members with OCD, and the individual's "tic-related" status appear to be potentially useful categorical distinctions. Although the OC symptom dimensions appear to be valid for all ages, it is unlikely that the underlying genetic vulnerability factors and neurobiological substrates for each of these symptom dimensions are the same across the course of development.

Gender differences in obsessive-compulsive symptom dimensions

The aim of our study was to assess the role of gender in OCD symptom dimensions with a multivariate analysis while controlling for history of tic disorders and age at onset of OCD. One hundred and eighty-six consecutive outpatients with a DSM-IV diagnosis of OCD were interviewed. Yale-Brown Obsessive-Compulsive Scale (YBOC-S), YBOC-S Symptom Checklist, and Hamilton Depression and Anxiety Scales were administered to all patients. Lifetime history of tic disorders was assessed with the tic inventory section of the Yale Global Tic Severity Scale. Age at onset of OCD was assessed by direct interview. Statistical analysis was carried out through logistic regression to calculate adjusted female:male odds ratios (OR) for each dimension. A relationship was found between gender and two main OCD dimensions: contamination/cleaning (higher in females; female:male OR=2.02, P=0.03) and sexual/religious (lower in females; female:male OR=0.41, P=0.03). We did not find gender differences in the aggressive/checking, symmetry/ordering, or hoarding dimensions. We also found a greater history of tic disorders in those patients with symptoms from the symmetry/ordering, dimension (P<0.01). Both symmetry/ordering and sexual/religious dimensions were associated with an earlier age at onset of OCD (P<0.05). Gender is a variable that plays a role in the expression of OCD, particularly the contamination/cleaning and sexual/religious dimensions. Our results underscore the need to examine the relationship between OCD dimensions and clinical variables such as gender, tics, age at onset and severity of the disorder to improve the identification of OCD subtypes.