A family study of obsessive-compulsive disorder

A Family Genetic Study of Obsessive Compulsive Disorder in Youth

OBJECTIVE

To use a family genetic study to evaluate familial risk of obsessive compulsive disorder (OCD) and common comorbid illnesses in first-degree relatives of pediatric-onset probands with primary OCD.

METHOD

One hundred and thirty youth with OCD and their 133 siblings and 241 parents and 49 pediatric controls were directly evaluated along multiple domains including psychopathology using structured diagnostic interviews and clinical corroboration.

RESULTS

Rates of anxiety, mood, disruptive behavior, and tic disorders were markedly elevated in the probands while rates in siblings were elevated at rates between the probands and controls. Twenty six percent of first-degree relatives had clinical OCD, 9% had chronic tics or Tourette's disorder, and 21% met criteria for ADHD.

CONCLUSION

Rates of familial transmission of OCD and common comorbid illnesses were significantly higher in our pediatric-onset probands than rates reported in the literature in relatives of those with adult-onset OCD.

Identifying risk loci for obsessive-compulsive disorder and shared genetic component with schizophrenia: A large-scale multi-trait association analysis with summary statistics

Due to limited samples, no genetic loci have been identified for obsessive-compulsive disorder (OCD) in genome-wide association studies. Additionally, although co-morbidities between OCD and schizophrenia (SCZ) were observed, their common genetic etiology was not completely known. Here, we conducted a comprehensive investigation regarding the genetic architecture of OCD and the common genetic foundation shared by OCD and SCZ using summary statistics data (2688 cases and 7037 controls for OCD; 53,386 cases and 77,258 controls for SCZ). We discovered significant genetic correlation between OCD and SCZ (r̂g=0.296, P = 2.82 × 10-11). We then performed two multi-trait association analyses to detect OCD-associated loci and colocalization analysis to detect causal variants. Parallel gene-level analyses were also implemented. We identified 323 OCD-relevant variants located within 12 loci, with four loci shared the same causal variants between OCD and SCZ. Further, the gene-level analyses discovered 8 OCD-associated genes. Finally, multiple functional analyses at both SNP and gene levels showed that these genetic association signals had significant enrichments in the regions of left ventricle and anterior cingulate cortex, and suggested an important role of pathways involving regulation of telomere maintenance, histone phosphorylation, and GnRH secretion. Overall, this study identified new genetic loci for OCD and provided substantial evidence supporting common genetic foundation underlying OCD and SCZ. The findings advanced our understanding of genetic architecture and pathophysiology of OCD as well as shedding light on shared genetic etiology of the two disorders.

The shared genetic risk factors between Tourette syndrome and obsessive-compulsive disorder

Tourette syndrome (TS) and obsessive-compulsive disorder (OCD) are two neuropsychiatric disorders that frequently co-occur. Previous evidence suggests a shared genetic diathesis underlying the comorbidity of TS and OCD. This review aims to comprehensively summarize the current literature on the genetic factors linked with TS and its comorbidities, with a focus on OCD. Family studies, linkage analysis, cytogenetic studies, and genome-wide association studies (GWAS) have played a pivotal role in identifying common and rare genetic variants connected with TS and OCD. Although the genetic framework of TS and OCD is complex and multifactorial, several susceptibility loci and candidate genes have been identified that might play a crucial role in the pathogenesis of both disorders. Additionally, post-infectious environmental elements have also been proposed to contribute to the development of TS-OCD, although the dynamics between genetic and environmental factors is not yet fully understood. International collaborations and studies with well-defined phenotypes will be crucial in the future to further elucidate the genetic basis of TS and OCD and to develop targeted therapeutic strategies for individuals suffering from these debilitating conditions.

The Motivational Determinants of Human Action, Their Neural Bases and Functional Impact in Adolescents With Obsessive-Compulsive Disorder

Background

Establishing the motivational influences on human action is essential for understanding choice and decision making in health and disease. Here we used tests of value-based decision making, manipulating both predicted and experienced reward values to assess the motivational control of goal-directed action in healthy adolescents and those with obsessive-compulsive disorder (OCD).

Methods

After instrumental training on a two action-two outcome probabilistic task, adolescents (n = 21) underwent Pavlovian conditioning using distinct stimuli predicting either the instrumental outcomes, a third outcome, or nothing. We then assessed functional magnetic resonance imaging during choice tests in which we varied the predicted value, using specific and general Pavlovian-instrumental transfer, and the experienced value, using outcome devaluation. To establish functional significance, we tested a matched cohort of adolescents with OCD (n = 20).

Results

In healthy adolescents, both predicted and experienced values influenced the performance of goal-directed actions, mediated by distinct orbitofrontal-striatal circuits involving the lateral orbitofrontal cortex (OFC) and medial OFC, respectively. However, in adolescents with OCD, choice was insensitive to changes in either predicted or experienced values. These impairments were related to hypoactivity in the lateral OFC and hyperactivity in the medial OFC during specific Pavlovian-instrumental transfer and hypoactivity in the anterior prefrontal cortex, caudate nucleus, and their connectivity in the devaluation test.

Conclusions

We found that predicted and experienced values exerted a potent influence on the performance of goal-directed actions in adolescents via distinct orbitofrontal- and prefrontal-striatal circuits. Furthermore, the influence of these motivational processes was severely blunted in OCD, as was the functional segregation of circuits involving medial and lateral OFC, producing dysregulated action control.

The genetic epidemiology of obsessive-compulsive disorder: a systematic review and meta-analysis

The first systematic review and meta-analysis of obsessive-compulsive disorder (OCD) genetic epidemiology was published approximately 20 years ago. Considering the relevance of all the studies published since 2001, the current study aimed to update the state-of-art knowledge on the field. All published data concerning the genetic epidemiology of OCD from the CENTRAL, MEDLINE, EMBASE, BVS, and OpenGrey databases were searched by two independent researchers until September 30, 2021. To be included, the articles had to fulfill the following criteria: OCD diagnosis provided by standardized and validated instruments; or medical records; inclusion of a control group for comparison and case-control, cohort or twin study designs. The analysis units were the first-degree relatives (FDRs) of OCD or control probands and the co-twins in twin pairs. The outcomes of interest were the familial recurrence rates of OCD and the correlations of OCS in monozygotic compared with dizygotic twins. Nineteen family, twenty-nine twin, and six population-based studies were included. The main findings were that OCD is a prevalent and highly familial disorder, especially among the relatives of children and adolescent probands, that OCD has a phenotypic heritability of around 50%; and that the higher OCS correlations between MZ twins were mainly due to additive genetic or to non-shared environmental components.

Behavioral Interventions for Children and Adults with Tic Disorder

Over the past decade, behavioral interventions have become increasingly recognized and recommended as effective first-line therapies for treating individuals with tic disorders. In this article, we describe a basic theoretical and conceptual framework through which the reader can understand the application of these interventions for treating tics. The three primary behavioral interventions for tics with the strongest empirical support (habit reversal, Comprehensive Behavioral Intervention for Tics, and exposure and response prevention) are described. Research on the efficacy and effectiveness of these treatments is summarized along with a discussion of the research evaluating the delivery of these treatments in different formats and modalities. The article closes with a review of the possible mechanisms of change underlying behavioral interventions for tics and areas for future research.

Obsessive-Compulsive Disorder and Its Cross-Generational Familial Association With Anxiety Disorders in a National Swedish Extended Adoption Study

Importance

We know little about the transmission of obsessive-compulsive disorder (OCD) across generations.

Objective

To evaluate the sources of parent-offspring transmission of OCD and familial cross-generational association with more typical anxiety disorders.

Design, Setting, and Participants

This Swedish population register-based study analyzed data for offspring born in Sweden from 1960 to 1995 from the following 4 family types: intact, not-lived-with biological father, lived-with stepfather, and adoptive. Follow-up occurred on December 31, 2018, and data were analyzed from April 6, 2022, to September 26, 2022.

Exposures

Three sources of parent-offspring resemblance: genes plus rearing, genes only, and rearing only.

Main Outcomes and Measures

Diagnoses of OCD, all anxiety disorders, generalized anxiety disorder (GAD), social phobia, and panic disorder were obtained from national inpatient, outpatient, and primary care medical registers. Parent-child resemblance was assessed by tetrachoric correlation (r).

Results

The offspring population consisted of 2 413 128 individuals; mean (SD) age at follow-up was 40.2 (10.7) years, 1 258 670 individuals (52.2%) were male, and 1 154 458 individuals (47.8%) were female. For each type of parent-child relationship, the best-estimate correlation for OCD for genes plus rearing was 0.19 (95% CI, 0.17 to 0.20); genes only, 0.18 (95% CI, 0.11 to 0.24); and rearing only, 0.04 (95% CI, -0.10 to 0.19). From bivariate adoption analyses, the cross-generational genetic correlations between OCD with anxiety disorder diagnostic categories were estimated as follows: for all anxiety disorders, 0.62 (95% CI, 0.46 to 0.77); GAD, 0.87 (95% CI, 0.53 to 1.00); social phobia, 0.70 (95% CI, 0.31 to 1.00); and panic disorder, 0.47 (95% CI, 0.20 to 0.73).

Conclusions and Relevance

This Swedish population register-based study found that OCD was transmitted from parents to children largely through a genetic relationship, with rearing playing a minor role. Viewed cross-generationally, OCD and anxiety disorders were moderately genetically correlated, with the genetic correlations strongest between OCD and GAD, intermediate for OCD and social phobia, and weakest between OCD and panic disorder. These genetic correlations were modestly attenuated when diagnostic hierarchies were imposed before analysis.

Childhood Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) frequently affects children and adolescents, with most cases beginning during this time. Symptoms of OCD in youth may present as exaggerated developmental concerns and excessive ritualistic behavior beyond what is part of normal development, yet low levels of insight may prevent recognition. Affected youth commonly have comorbid neurodevelopmental diagnoses, especially males. Early detection and intervention are critical to recovery and remission, as well as family involvement in treatment. Cognitive behavioral therapy and serotonin reuptake inhibitors are first-line treatments.

Deep brain stimulation for refractory obsessive-compulsive disorder: A review and analysis of the FDA MAUDE database

Background:

Deep brain stimulation (DBS) is used as a treatment option for patients diagnosed with a form of obsessive-compulsive disorder (OCD) that is highly resistant to conventional treatment methods. In 2009, DBS was granted a humanitarian device exemption-approval by the Food and Drug Administration after promising preliminary data. Monitoring of long-term safety data through post market surveillance of adverse events has not yet been conducted for DBS in OCD patients. This study aims to address this critical knowledge gap.

Methods:

All patient- and device-related (PR; DR) reports from January 1, 2012, to December 31, 2021, were downloaded and compiled from the manufacturer and user facility device experience (MAUDE) database pertaining to DBS for OCD using the product class name “Deep Brain Stimulator For OCD.” Data in this study were examined using descriptive statistics to evaluate for frequency of reporting.

Results:

The most frequently reported PR adverse event categories included psychiatric (40%), neurological (19%), other (14%), decreased therapeutic response (10%), and infections (10%). The most frequent DR reports were high impedance (14%), energy output problem (7%), battery problem (7%), malposition of device (7%), and improper/incorrect procedure or method (7%).

Conclusion:

The PR and DR adverse events in our study align with the previous findings of adverse events. They also further solidify that DBS for refractory OCD may be a viable option for the right patient population. However, further studies are essential given the limitations of the MAUDE database.

Alterations of default mode and cingulo-opercular salience network and frontostriatal circuit: A candidate endophenotype of obsessive-compulsive disorder

Background It is gradually becoming clear that obsessive-compulsive disorder (OCD) patients have aberrant resting-state large-scale intrinsic networks of cingulo-opercular salience (SN), default mode (DMN), and front-parietal network (FPN). However, it remains unknown whether unaffected first-degree relatives of OCD patients have these alterations as a vulnerability marker to the disorder. Methods We performed resting-state functional magnetic resonance imaging (rsfMRI) scans of 47 medication-free OCD patients, 21 unaffected healthy first-degree relatives of OCD patients, and 62 healthy control (HC) participants. We explored differences between the three groups in the functional connectivity from SN (seeds: anterior-insula (AI) and dorsal anterior cingulate cortex (dACC)), DMN (seeds: medial prefrontal cortex (MPFC) and posterior parietal cortex (PCC)), and FPN (seeds: dorsolateral prefrontal cortex (DLPFC)). Results Compared to HC, both OCD patients and first-degree relatives showed significantly greater functional connectivity between AI and PCC and between DLPFC and the thalamus. Compared to first-degree relatives and HC, OCD patients showed reduced functional connectivity between PCC and DLPFC, and this altered functional connectivity was negatively correlated with anxiety and depressive symptom within OCD group. Conclusions OCD patients and unaffected first-degree relatives of OCD patients showed overlapping alterations in resting state functional connectivity between the regions of SN and DMN and between DLPFC and the thalamus. Our results suggested that alterations between large-scale intrinsic networks and within the dorsal cognitive cortico-striato-thalamo-cortical (CSTC) circuit could represent endophenotype markers of OCD.

Aberrant rich club organization in patients with obsessive-compulsive disorder and their unaffected first-degree relatives

Recent studies suggested that the rich club organization promoting global brain communication and integration of information, may be abnormally increased in obsessive-compulsive disorder (OCD). However, the structural and functional basis of this organization is still not very clear. Given the heritability of OCD, as suggested by previous family-based studies, we hypothesize that aberrant rich club organization may be a trait marker for OCD. In the present study, 32 patients with OCD, 30 unaffected first-degree relatives (FDR) and 32 healthy controls (HC) underwent diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI). We examined the structural rich club organization and its interrelationship with functional coupling. Our results showed that rich club and peripheral connection strength in patients with OCD was lower than in HC, while it was intermediate in FDR. Finally, the coupling between structural and functional connections of the rich club, was decreased in FDR but not in OCD relative to HC, which suggests a buffering mechanism of brain functions in FDR. Overall, our findings suggest that alteration of the rich club organization may reflect a vulnerability biomarker for OCD, possibly buffered by structural and functional coupling of the rich club.

The Role of Stress in Obsessive-Compulsive Disorder: A Narrative Review

Obsessive-compulsive disorder (OCD) has a worldwide prevalence of 2%-3%. Characterized by the presence of either one or two core symptoms-obsessions and compulsions-it generally runs a chronic course and may cause serious functional impairment. Though previously thought to be of psychogenic origin, the pathophysiology of OCD is now understood to be more complex. A multitude of environmental factors have been shown to contribute to the development of OCD, including infection, neonatal complications, childhood trauma, occurrence of stressful events, and brain injury. It has also been proposed that genetic vulnerability may play a role in OCD pathology, although candidate genes have yet to be identified. Likewise, although it is widely accepted that stress plays a role in OCD pathophysiology, the mechanisms remain unclear. Observations from the clinics indicate that stress may serve as both a triggering and aggravating factor, meaning it can prompt symptoms to appear while also contributing to their exacerbation. Additionally, dysfunction of the hypothalamic-pituitary-adrenal axis and impaired stress response have been identified in OCD patients. In this review, we analyze the role of stress in the pathophysiology of OCD, complemented by relevant findings from recent animal studies.

Genetics of obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is a psychiatric disorder with multiple symptom dimensions (e.g. contamination, symmetry). OCD clusters in families and decades of twin studies clearly demonstrate an important role for genetics in the etiology of the disorder.

METHODS

In this review, we summarize the genetic epidemiology and molecular genetic studies of OCD and obsessive-compulsive symptoms.

RESULTS

OCD is a heritable, polygenic disorder with contributions from both common and rare variants, including de novo deleterious variations. Multiple studies have provided reliable support for a large additive genetic contribution to liability to OCD, with discrete OCD symptom dimensions having both shared and unique genetic risks. Genome-wide association studies have not produced significant results yet, likely because of small sample sizes, but larger meta-analyses are forthcoming. Both twin and genome-wide studies show that OCD shares genetic risk with its comorbid conditions (e.g. Tourette syndrome and anorexia nervosa).

CONCLUSIONS

Despite significant efforts to uncover the genetic basis of OCD, the mechanistic understanding of how genetic and environmental risk factors interact and converge at the molecular level to result in OCD's heterogeneous phenotype is still mostly unknown. Future investigations should increase ancestral genetic diversity, explore age and/or sex differences in genetic risk for OCD and expand the study of pharmacogenetics, gene expression, gene × environment interactions and epigenetic mechanisms for OCD.

Bidirectional Behavioral Selection in Mice: A Novel Pre-clinical Approach to Examining Compulsivity

Obsessive-compulsive disorder (OCD) and related disorders (OCRD) is one of the most prevalent neuropsychiatric disorders with no definitive etiology. The pathophysiological attributes of OCD are driven by a multitude of factors that involve polygenic mechanisms, gender, neurochemistry, physiological status, environmental exposures and complex interactions among these factors. Such complex intertwining of contributing factors imparts clinical heterogeneity to the disorder making it challenging for therapeutic intervention. Mouse strains selected for excessive levels of nest- building behavior exhibit a spontaneous, stable and predictable compulsive-like behavioral phenotype. These compulsive-like mice exhibit heterogeneity in expression of compulsive-like and other adjunct behaviors that might serve as a valuable animal equivalent for examining the interactions of genetics, sex and environmental factors in influencing the pathophysiology of OCD. The current review summarizes the existing findings on the compulsive-like mice that bolster their face, construct and predictive validity for studying various dimensions of compulsive and associated behaviors often reported in clinical OCD and OCRD.

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.

Neurocognitive Endophenotypes of OCD

In this chapter, I address the concept of endophenotypes for obsessive-compulsive disorder (OCD). Endophenotypes are objective and heritable quantitative traits hypothesized to be more biologically tractable than distal clinical phenotypes. This approach has been adopted to gain a better understanding of psychiatric conditions in general. It is theorized that endophenotypes will particularly assist in clarifying both the diagnostic status and aetiological origins of complex neuropsychiatric conditions such as OCD. At the cognitive level, separable constructs of relevance for OCD have been identified. The prevailing model for OCD assumes the development of abnormalities within fronto-striatal neural circuits leading to impairment of executive functions and their neuropsychological subcomponents. Here, I address whether this model can guide towards the identification of endophenotypes for this condition and discuss possible implications.

A population-based family clustering study of tic-related obsessive-compulsive disorder

In the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), obsessive-compulsive disorder (OCD) included a new "tic-related" specifier. However, strong evidence supporting tic-related OCD as a distinct subtype of OCD is lacking. This study investigated whether, at the population level, tic-related OCD has a stronger familial load than non-tic-related OCD. From a cohort of individuals born in Sweden between 1967 and 2007 (n = 4,085,367; 1257 with tic-related OCD and 20,975 with non-tic-related OCD), we identified all twins, full siblings, maternal and paternal half siblings, and cousins. Sex- and birth year-adjusted hazard ratios (aHR) were calculated to estimate the risk of OCD in relatives of individuals with OCD with and without comorbid tics, compared with relatives of unaffected individuals. We found that OCD is a familial disorder, regardless of comorbid tic disorder status. However, the risk of OCD in relatives of individuals with tic-related OCD was considerably greater than the risk of OCD in relatives of individuals with non-tic-related OCD (e.g., risk for full siblings: aHR = 10.63 [95% CI, 7.92-14.27] and aHR = 4.52 [95% CI, 4.06-5.02], respectively; p value for the difference < 0.0001). These differences remained when the groups were matched by age at first OCD diagnosis and after various sensitivity analyses. The observed familial patterns of OCD in relation to tics were not seen in relation to other neuropsychiatric comorbidities. Tic-related OCD is a particularly familial subtype of OCD. The results have important implications for ongoing gene-searching efforts.

Cutting-edge genetics in obsessive-compulsive disorder

This article reviews recent advances in the genetics of obsessive-compulsive disorder (OCD). We cover work on the following: genome-wide association studies, whole-exome sequencing studies, copy number variation studies, gene expression, polygenic risk scores, gene–environment interaction, experimental animal systems, human cell models, imaging genetics, pharmacogenetics, and studies of endophenotypes. Findings from this work underscore the notion that the genetic architecture of OCD is highly complex and shared with other neuropsychiatric disorders. Also, the latest evidence points to the participation of gene networks involved in synaptic transmission, neurodevelopment, and the immune and inflammatory systems in this disorder. We conclude by highlighting that further study of the genetic architecture of OCD, a great part of which remains to be elucidated, could benefit the development of diagnostic and therapeutic approaches based on the biological basis of the disorder. Studies to date revealed that OCD is not a simple homogeneous entity, but rather that the underlying biological pathways are variable and heterogenous. We can expect that translation from bench to bedside, through continuous effort and collaborative work, will ultimately transform our understanding of what causes OCD and thus how best to treat it.

The effects of acute serotonin challenge on executive planning in patients with obsessive-compulsive disorder (OCD), their first-degree relatives, and healthy controls

RATIONALE

Obsessive-compulsive disorder (OCD) is characterized by executive function impairment and by clinical responsivity to selective serotonin reuptake inhibitors (SSRIs). Executive planning deficits constitute a candidate endophenotype for OCD. It is not known whether this endophenotype is responsive to acute serotonin manipulation.

OBJECTIVE

The study aimed to investigate the effects of acute SSRI administration on executive function in patients with OCD, first-degree relatives of patients with OCD, and healthy controls.

METHODS

A randomized double-blind cross-over study assessed the effects of single-dose escitalopram (20 mg) and placebo on executive planning in 24 patients with OCD, 13 clinically unaffected first-degree relatives of patients with OCD, and 28 healthy controls. Performance on a Tower of London task measuring executive planning was assessed 4 h after oral administration of the pharmacological challenge/placebo and compared across and within groups using a mixed model analysis of variance.

RESULTS

On the outcome measure of interest, i.e., the mean number of choices to obtain the correct solution, there was a marginally significant effect of group (F(2, 59) = 3.1; p = 0.052), with patients (least square (LS) mean 1.43; standard error [SE] 0.06; 95% confidence interval (CI), 1.31-1.55) and their relatives (LS mean 1.46; SE 0.08; 95% CI, 1.30-1.62) performing worse than matched healthy controls (LS mean 1.26; SE 0.05; 95% CI, 1.15-1.37) on placebo. There was a trend towards a significant group × treatment interaction (F(2, 58) = 2.8, p = 0.069), with post hoc tests showing (i) patients (p = 0.009; LS mean difference 0.23; SE 0.08) and relatives (p = 0.03; LS mean difference 0.22; SE 0.10) were more impaired compared to controls and (ii) escitalopram was associated with improved executive planning in patients with OCD (p = 0.013; LS mean difference 0.1; SE 0.04), but not other groups (both p > 0.1; controls: LS mean difference - 0.03; SE 0.04; relatives: LS mean difference 0.02; SE 0.05).

CONCLUSION

Our findings are consistent with a view that there is impaired executive planning in OCD and that this constitutes a behavioural endophenotype. In patients with OCD, but not in relatives, acute SSRI administration ameliorated this deficit. Further investigation is needed to understand common and differential involvement of neurochemical systems in patients with OCD and their relatives.

The polygenic risk for obsessive-compulsive disorder is associated with the personality trait harm avoidance

OBJECTIVE

Obsessive-compulsive disorder (OCD) is a complex psychiatric disorder with a substantial genetic contribution. While the specific variants underlying OCD's heritability are still unknown, findings from genome-wide association studies (GWAS) corroborate the importance of common SNPs explaining the phenotypic variance in OCD. Investigating associations between the genetic liability for OCD, as reflected by a polygenic risk score (PRS), and potential endophenotypes of the disorder, such as the personality trait harm avoidance, may aid the understanding of functional pathways from genes to diagnostic phenotypes.

METHODS

We derived PRS for OCD at several P-value thresholds based on the latest Psychiatric Genomics Consortium OCD GWAS (2688 cases, 7037 controls) in an independent sample of OCD patients (n = 180), their unaffected first-degree relatives (n = 108) and healthy controls (n = 200). Using linear regression, we tested whether these PRS are associated with the personality trait harm avoidance.

RESULTS

Results showed that OCD PRS significantly predicted OCD status, with patients having the highest scores and relatives having intermediate scores. Furthermore, the genetic risk for OCD was associated with harm avoidance across the entire sample, and among OCD patients. As indicated by mediation analyses, harm avoidance mediated the association between the OCD PRS and OCD caseness. These results were observed at multiple P-value thresholds and persisted after the exclusion of patients with a current comorbid major depressive or anxiety disorder.

CONCLUSION

Our findings support the polygenic nature of OCD and further validate harm avoidance as a candidate endophenotype and diathesis of OCD.

Organic Cation Transporters in Health and Disease

The organic cation transporters (OCTs) OCT1, OCT2, OCT3, novel OCT (OCTN)1, OCTN2, multidrug and toxin exclusion (MATE)1, and MATE kidney-specific 2 are polyspecific transporters exhibiting broadly overlapping substrate selectivities. They transport organic cations, zwitterions, and some uncharged compounds and operate as facilitated diffusion systems and/or antiporters. OCTs are critically involved in intestinal absorption, hepatic uptake, and renal excretion of hydrophilic drugs. They modulate the distribution of endogenous compounds such as thiamine, L-carnitine, and neurotransmitters. Sites of expression and functions of OCTs have important impact on energy metabolism, pharmacokinetics, and toxicity of drugs, and on drug-drug interactions. In this work, an overview about the human OCTs is presented. Functional properties of human OCTs, including identified substrates and inhibitors of the individual transporters, are described. Sites of expression are compiled, and data on regulation of OCTs are presented. In addition, genetic variations of OCTs are listed, and data on their impact on transport, drug treatment, and diseases are reported. Moreover, recent data are summarized that indicate complex drug-drug interaction at OCTs, such as allosteric high-affinity inhibition of transport and substrate dependence of inhibitor efficacies. A hypothesis about the molecular mechanism of polyspecific substrate recognition by OCTs is presented that is based on functional studies and mutagenesis experiments in OCT1 and OCT2. This hypothesis provides a framework to imagine how observed complex drug-drug interactions at OCTs arise. Finally, preclinical in vitro tests that are performed by pharmaceutical companies to identify interaction of novel drugs with OCTs are discussed. Optimized experimental procedures are proposed that allow a gapless detection of inhibitory and transported drugs.

Cognitive performance in children and adolescents at high-risk for obsessive-compulsive disorder

BACKGROUND

Cognitive performance has been studied in adults with obsessive-compulsive symptoms (OCS) and in adult relatives of patients with obsessive-compulsive disorder (OCD) Meanwhile, few studies have been conducted with children under the same conditions. This study compared the neurocognitive domains previously associated with dysfunction in OCD, especially visuoconstructive ability, visuospatial memory, executive functions, and intelligence, in children and adolescents at high risk (HR) for OCD (n = 18) and non-OCD controls (NOC) (n = 31).

METHODS

For the HR group, we considered the first-degree relatives of patients with OCD that present OCS, but do not meet diagnostic criteria for OCD. Psychiatric diagnosis was assessed by experienced clinicians using the Structured Clinical Interview for DSM-IV and OCS severity was measured by the Yale-Brown Obsessive-Compulsive Scale. Neurocognitive assessment was performed with a comprehensive neuropsychological battery. Performance on the cognitive domains was compared between groups using Multivariate Analysis of Variance, whereas performance on the neuropsychological variables was compared between groups using independent t-tests in a cognitive subdomain analysis.

RESULTS

The cognitive domain analysis revealed a trend towards significance for impairments in the motor and processing speed domain (p = 0.019; F = 3.12) in the HR group. Moreover, the cognitive subdomain analysis identified a statistically significant underperformance in spatial working memory in the HR group when compared to the NOC group (p = 0.005; t = - 2.94), and a trend towards significance for impairments in non-verbal memory and visuoconstructive tasks in the HR group.

CONCLUSIONS

Our results suggest impairments in spatial working memory and motor and processing speed in a non-clinical sample of HR participants. Considering the preliminary nature of our findings, further studies investigating these neurocognitive domains as potential predictors of pediatric OCD are warranted.

De Novo Damaging DNA Coding Mutations Are Associated With Obsessive-Compulsive Disorder and Overlap With Tourette's Disorder and Autism

BACKGROUND

Obsessive-compulsive disorder (OCD) is a debilitating neuropsychiatric disorder with a genetic risk component, yet identification of high-confidence risk genes has been challenging. In recent years, risk gene discovery in other complex psychiatric disorders has been achieved by studying rare de novo (DN) coding variants.

METHODS

We performed whole-exome sequencing in 222 OCD parent-child trios (184 trios after quality control), comparing DN variant frequencies with 777 previously sequenced unaffected trios. We estimated the contribution of DN mutations to OCD risk and the number of genes involved. Finally, we looked for gene enrichment in other datasets and canonical pathways.

RESULTS

DN likely gene disrupting and predicted damaging missense variants are enriched in OCD probands (rate ratio, 1.52; p = .0005) and contribute to risk. We identified 2 high-confidence risk genes, each containing 2 DN damaging variants in unrelated probands: CHD8 and SCUBE1. We estimate that 34% of DN damaging variants in OCD contribute to risk and that DN damaging variants in approximately 335 genes contribute to risk in 22% of OCD cases. Furthermore, genes harboring DN damaging variants in OCD are enriched for those reported in neurodevelopmental disorders, particularly Tourette's disorder and autism spectrum disorder. An exploratory network analysis reveals significant functional connectivity and enrichment in canonical pathways, biological processes, and disease networks.

CONCLUSIONS

Our findings show a pathway toward systematic gene discovery in OCD via identification of DN damaging variants. Sequencing larger cohorts of OCD parent-child trios will reveal more OCD risk genes and will provide needed insights into underlying disease biology.

Genetic meta-analysis of obsessive-compulsive disorder and self-report compulsive symptoms

We investigated whether obsessive-compulsive (OC) symptoms from a population-based sample could be analyzed to detect genetic variants influencing obsessive-compulsive disorder (OCD). We performed a genome-wide association studies (GWAS) on the obsession (rumination and impulsions) and compulsion (checking, washing, and ordering/precision) subscales of an abbreviated version of the Padua Inventory (N = 8,267 with genome-wide genotyping and phenotyping). The compulsion subscale showed a substantial and significant positive genetic correlation with an OCD case-control GWAS (r _G = 0.61, p = .017) previously published by the Psychiatric Genomics Consortium (PGC-OCD). The obsession subscale and the total Padua score showed no significant genetic correlations (r _G = -0.02 and r _G = 0.42, respectively). A meta-analysis of the compulsive symptoms GWAS with the PGC-OCD revealed no genome-wide significant Single-Nucleotide Polymorphisms (SNPs combined N = 17,992, indicating that the power is still low for individual SNP effects). A gene-based association analysis, however, yielded two novel genes (WDR7 and ADCK1). The top 250 genes in the gene-based test also showed a significant increase in enrichment for psychiatric and brain-expressed genes. S-Predixcan testing showed that for genes expressed in hippocampus, amygdala, and caudate nucleus significance increased in the meta-analysis with compulsive symptoms compared to the original PGC-OCD GWAS. Thus, the inclusion of dimensional symptom data in genome-wide association on clinical case-control GWAS of OCD may be useful to find genes for OCD if the data are based on quantitative indices of compulsive behavior. SNP-level power increases were limited, but aggregate, gene-level analyses showed increased enrichment for brain-expressed genes related to psychiatric disorders, and increased association with gene expression in brain tissues with known emotional, reward processing, memory, and fear-formation functions.

Mental health dished up-the use of iPSC models in neuropsychiatric research

Genetic and molecular mechanisms that play a causal role in mental illnesses are challenging to elucidate, particularly as there is a lack of relevant in vitro and in vivo models. However, the advent of induced pluripotent stem cell (iPSC) technology has provided researchers with a novel toolbox. We conducted a systematic review using the PRISMA statement. A PubMed and Web of Science online search was performed (studies published between 2006–2020) using the following search strategy: hiPSC OR iPSC OR iPS OR stem cells AND schizophrenia disorder OR personality disorder OR antisocial personality disorder OR psychopathy OR bipolar disorder OR major depressive disorder OR obsessive compulsive disorder OR anxiety disorder OR substance use disorder OR alcohol use disorder OR nicotine use disorder OR opioid use disorder OR eating disorder OR anorexia nervosa OR attention-deficit/hyperactivity disorder OR gaming disorder. Using the above search criteria, a total of 3515 studies were found. After screening, a final total of 56 studies were deemed eligible for inclusion in our study. Using iPSC technology, psychiatric disease can be studied in the context of a patient’s own unique genetic background. This has allowed great strides to be made into uncovering the etiology of psychiatric disease, as well as providing a unique paradigm for drug testing. However, there is a lack of data for certain psychiatric disorders and several limitations to present iPSC-based studies, leading us to discuss how this field may progress in the next years to increase its utility in the battle to understand psychiatric disease.

Serum zonulin and claudin-5 levels in children with obsessive-compulsive disorder

Background: Obsessive-compulsive disorder (OCD), a chronically debilitating neuropsychiatric disorder, is characterized by distinctive and recurrent obsessions and/or compulsions. An increasing number of evidence indicates that sophisticated interactions between different neurobiological factors play a part in OCD etiology, but the certain underlying mechanisms are still mainly unknown. The present research aimed to explore whether the concentrations of serum zonulin and claudin-5 vary between OCD patients and healthy controls. The present research also intended to explore whether there is an association between zonulin and claudin-5 concentrations and OCD severity.Methods: Twenty-four (13 boys and 11 girls) OCD patients and 24 (13 boys and 11 girls) healthy controls were included in this study. The clinical severity of the OCD symptoms was evaluated by the Children's Yale-Brown Obsessive-Compulsive Scale and the Maudsley Obsessive-Compulsive Inventory. Participants also filled out the Revised Child Anxiety and Depression Scales-Child Version to determine the anxiety and depression levels of the children. Venous blood samples were collected, and serum zonulin and claudin-5 levels were measured.Results: Serum claudin-5 levels were found to be significantly higher in OCD patient whereas serum zonulin levels were not significantly different between the groups.Conclusions: Taken together with our results, our study suggests that dysregulation of the blood-brain barrier, especially claudin-5, may be involved in the etiology of OCD.

Obsessive-compulsive personality disorder traits and personality dimensions in parents of children with obsessive-compulsive disorder

Purpose

To compare patterns of temperament and character and the prevalence of Obsessive-Compulsive Personality Disorder (OCPD) and OCPD traits in parents of children with OCD and parents of healthy controls.

Methods

TCI and SCID-II were administered to 63 parents of 32 children with OCD and 63 parents of age- and sex-matched controls with no psychiatric diagnosis. Interviewers were not blind to proband status. Personality dimension scores and frequencies of OCPD criteria in both groups were compared after excluding parents with a diagnosis of OCD. Relationships between TCI dimensions and OCPD symptoms in parents and the clinical characteristics of OCD children were also studied.

Results

Parents of OCD children presented significantly higher scores in harm avoidance and lower scores in self-directedness, cooperativeness and reward dependence than parents of healthy children. A higher incidence of OCPD was found in parents of probands (p < 0.02). Hoarding, perfectionism and preoccupation with details were significantly more frequent in parents of OCD children. Counting, ordering and cleaning compulsions in OCD children predicted elevated odds of perfectionism and rigidity in their parents.

Conclusions

The existence of the dimensional personality profile associated with OCD in parents of children with OCD and the higher number of OCPD criteria in these parents in comparison to parents of healthy children highlight the importance of the role of personality factors in familial OCD.

Clinical characteristics of hoarding disorder in Japanese patients

Previous studies have reported clinical characteristics of hoarding disorder (HD), such as early onset, a chronic course, familiality, high unmarried rate, and high rates of comorbidities. However, clinical research targeting Japanese HD patients has been very limited. As a result, there is a low recognition of HD in Japan, leading to insufficient evaluation and treatment of Japanese HD patients.

The aim of the current study was to delineate the clinical characteristics of Japanese HD patients. Thirty HD patients, 20 obsessive-compulsive disorder (OCD) patients, and 21 normal controls (NC) were targeted in this study.

The HD group had a tendency toward higher familiality, earlier onset, and longer disease duration compared to the OCD group. In addition, the HD group showed a significantly higher unmarried rate than the NC group. The top two comorbidities in the HD group were major depressive disorder (56.7%) and attention-deficit/hyperactivity disorder (26.7%). The HD group had significantly higher scores on hoarding rating scales and lower scores on the Global Assessment of Functioning Scale than the other two groups.

The current study showed a clinical trend in Japanese HD patients similar to previous studies in various countries, suggesting that HD may be a universal disease with consistent clinical symptoms.

Abnormal Anhedonia as a Potential Endophenotype in Obsessive-Compulsive Disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is often accompanied by cognitive, particularly executive function, impairments. Recently, anhedonia has emerged as an apparently important symptom of OCD reflecting altered emotion regulation. These two aspects are often comorbid in OCD. However, little is known about whether anhedonia may be a trait marker for OCD.

METHODS

To verify the role of executive function and evaluate the role of anhedonia in OCD and its relationship with OCD symptoms, we recruited 60 OCD patients, 30 unaffected first-degree relatives (FDRs), and 60 healthy controls (HCs). Participants completed psychometric testing to assess depression, anxiety, and anhedonia symptoms, as well as two cognitive tests to assess executive function, namely the Wisconsin Card Sorting Test (WCST) and the Stroop Color-Word Test (SCWT).

RESULTS

Compared to HCs, OCD patients and FDRs had significantly lower anticipatory and consummatory pleasure scores. The severity of anticipatory anhedonia correlated positively with obsessive-compulsive symptoms (r = 0.253, p = 0.009), even after controlling for depression and anxiety symptoms. Compared to HCs, OCD patients and FDRs made more errors and achieved fewer categories in the WCST. For all three SWCT components, OCD patients and FDRs took more time to name colors than HCs, but the three groups had similar numbers of errors.

CONCLUSION

This family-based study showed dampened pleasure together with cognitive dysfunction in OCD patients. The similar consummatory pleasure findings between OCD and FDR groups suggest anhedonia may be considered as a candidate OCD endophenotype.

The Effectiveness of Selective Serotonin Reuptake Inhibitors for Treatment of Obsessive-Compulsive Disorder in Adolescents and Children: A Systematic Review and Meta-Analysis

Background: Obsessive-compulsive disorder (OCD) is a common behavioral disorder among adolescents and children. The selective serotonin reuptake inhibitors (SSRIs) are the first pharmacological choice for this condition due to mild adverse effect profile. Objective: This systematic review was performed to evaluate the efficacy of SSRI for OCD in adolescents and children. Methods: Search terms were entered into PubMed, PsycINFO, Scopus, CINAHL, and Google Scholar. The included studies were randomized, placebo-controlled trials of SSRIs conducted in populations of children and adolescents younger than 18 years. Change from baseline Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS), end-treatment CY-BOCS with respective SD, and response and remission rates were collected for continuous and dichotomous outcome assessment, respectively. Cochrane Rev Man software was used for meta-analyses, providing Forest plots where applicable. Results: SSRIs were superior to placebo with a small effect size. There was no additional benefit of combination treatment over cognitive behavioral therapy (CBT) alone, but CBT added substantial benefit to SSRI monotherapy. Fluoxetine and sertraline appear to be superior to fluvoxamine. Conclusion: The results of current systematic review and meta-analysis support the existing National Institute for Health and Care Excellence (NICE) guidelines for choosing CBT as first line of treatment and substituting it with SSRI, depending on patient preference. Adding CBT to current SSRI treatment is effective for non-responders and partial responders, but adding SSRI to ongoing CBT does not prove beneficial. The SSRIs have different effectiveness, and their relative efficacy remains to be investigated.

Eye movement tracking in pediatric obsessive compulsive disorder

Till date researchers have elucidated the neurobiological substrates in OCD using methods like neuroimaging. However, a potential biomarker is still elusive. The present study is an attempt to identify a potential biomarker in pediatric OCD using eye tracking. The present study measured pro-saccade and anti-saccade parameters in 36 cases of pediatric OCD and 31 healthy controls. There was no significant difference between cases and controls in the error rate, peak velocity, position gain and latency measures in both pro-saccade and anti-saccade eye tracking tasks. With age, anti-saccades become slower in velocity, faster in response and more accurate irrespective of disorder status of the child. Pro-saccades also show a similar effect that is less prominent than anti-saccades. Gain measures more significantly vary with age in children with OCD than the controls, whereas latency measures positively correlated with age in children with OCD as opposed to being negatively correlated in the controls. Findings of this study do not support any of the eye tracking measures as putative diagnostic bio-markers in OCD. However, latency and gain parameters across different age groups in anti-saccade tasks need to be explored in future studies.

No Association of Variants of the NPY-System With Obsessive-Compulsive Disorder in Children and Adolescents

Obsessive-compulsive disorder (OCD) causes severe distress and is therefore counted by the World Health Organisation (WHO) as one of the 10 most impairing illnesses. There is evidence for a strong genetic underpinning especially in early onset OCD (eoOCD). Though several genes involved in neurotransmission have been reported as candidates, there is still a need to identify new pathways. In this study, we focussed on genetic variants of the Neuropeptide Y (NPY) system. NPY is one of the most abundant neuropeptides in the human brain with emerging evidence of capacity to modulate stress response, which is of high relevance in OCD. We focussed on tag-SNPs of NPY and its receptor gene NPY1R in a family-based approach. The sample comprised 86 patients (children and adolescents) with eoOCD with both their biological parents. However, this first study on genetic variants of the NPY-system could not confirm the association between the investigated SNPs and eoOCD. Based on the small sample size results have to be interpreted as preliminary and should be replicated in larger samples. However, also in an additional GWAS analysis in a large sample, we could not observe an associations between NPY and OCD. Overall, these preliminary results point to a minor role of NPY on the stress response of OCD.

Early intervention for obsessive compulsive disorder: An expert consensus statement

Obsessive-compulsive disorder (OCD) is common, emerges early in life and tends to run a chronic, impairing course. Despite the availability of effective treatments, the duration of untreated illness (DUI) is high (up to around 10 years in adults) and is associated with considerable suffering for the individual and their families. This consensus statement represents the views of an international group of expert clinicians, including child and adult psychiatrists, psychologists and neuroscientists, working both in high and low and middle income countries, as well as those with the experience of living with OCD. The statement draws together evidence from epidemiological, clinical, health economic and brain imaging studies documenting the negative impact associated with treatment delay on clinical outcomes, and supporting the importance of early clinical intervention. It draws parallels between OCD and other disorders for which early intervention is recognized as beneficial, such as psychotic disorders and impulsive-compulsive disorders associated with problematic usage of the Internet, for which early intervention may prevent the development of later addictive disorders. It also generates new heuristics for exploring the brain-based mechanisms moderating the 'toxic' effect of an extended DUI in OCD. The statement concludes that there is a global unmet need for early intervention services for OC related disorders to reduce the unnecessary suffering and costly disability associated with under-treatment. New clinical staging models for OCD that may be used to facilitate primary, secondary and tertiary prevention within this context are proposed.

Schizotypy and smooth pursuit eye movements as potential endophenotypes of obsessive-compulsive disorder

Patients with obsessive-compulsive disorder (OCD) show dysfunctions of the fronto-striatal circuitry, which imply corresponding oculomotor deficits including smooth pursuit eye movements (SPEM). However, evidence for a deficit in SPEM is inconclusive, with some studies reporting reduced velocity gain while others did not find any SPEM dysfunctions in OCD patients. Interestingly, psychosis-like traits have repeatedly been linked to both OCD and impaired SPEM. Here, we examined a large sample of n = 168 patients with OCD, n = 93 unaffected first-degree relatives and n = 171 healthy control subjects to investigate whether elevated levels of schizotypy and SPEM deficits represent potential endophenotypes of OCD. We applied a SPEM task with high demands on predictive pursuit that is more sensitive to assess executive dysfunctions than a standard task with continuous visual feedback, as episodes of target blanking put increased demands on basal ganglia and prefrontal involvement. Additionally, we examined the relation between schizotypy and SPEM performance in OCD patients and their relatives. Results indicate that OCD patients and unaffected relatives do not show deficient performance in either standard or predictive SPEM. Yet, both patients and relatives exhibited elevated levels of schizotypy, and schizotypy was significantly correlated with velocity gain during standard trials in unmedicated and depression-free OCD patients. These findings highlight the role of schizotypy as a candidate endophenotype of OCD and add to the growing evidence for predisposing personality traits in OCD. Furthermore, intact gain may represent a key characteristic that distinguishes the OCD and schizophrenia patient populations.

Do polygenic risk and stressful life events predict pharmacological treatment response in obsessive compulsive disorder? A gene-environment interaction approach

The rate of response to pharmacological treatment in Obsessive-compulsive disorder (OCD) oscillates between 40 and 70%. Genetic and environmental factors have been associated with treatment response in OCD. This study analyzes the predictive ability of a polygenic risk score (PRS) built from OCD-risk variants, for treatment response in OCD, and the modulation role of stressful life events (SLEs) at the onset of the disorder. PRSs were calculated for a sample of 103 patients. Yale-Brown Obsessive Compulsive Scale (YBOCS) scores were obtained before and after a 12-week treatment. Regression analyses were performed to analyze the influence of the PRS and SLEs at onset on treatment response. PRS did not predict treatment response. The best predictive model for post-treatment YBOCS (post YBOCS) included basal YBOCS and age. PRS appeared as a predictor for basal and post YBOCS. SLEs at onset were not a predictor for treatment response when included in the regression model. No evidence for PRS predictive ability for treatment response was found. The best predictor for treatment response was age, agreeing with previous literature specific for SRI treatment. Suggestions are made on the possible role of neuroplasticity as a mediator on this association. PRS significantly predicted OCD severity independent on pharmacological treatment. SLE at onset modulation role was not evidenced. Further research is needed to elucidate the genetic and environmental bases of treatment response in OCD.

Neurocognitive deficits in obsessive-compulsive disorder: A selective review

Obsessive-compulsive disorder (OCD) is a debilitating mental illness characterized by an early onset and chronic course. Evidence from several lines of research suggests significant neuropsychological deficits in patients with OCD; executive dysfunction and nonverbal memory deficits have been reported consistently in OCD. These deficits persist despite controlling potential confounders such as comorbidity, severity of illness, and medications. Neuropsychological impairments are independent of illness severity, thus suggesting that the neuropsychological deficits are trait markers of the disease. In addition, these deficits are seen in first-degree relatives of individuals with OCD. These reports suggest that neuropsychological deficits are potential endophenotype markers in OCD. Neuropsychological studies in pediatric OCD are limited; they show impairments of small effect size across multiple domains but with doubtful clinical significance. Preliminary evidence shows that different symptom dimensions of OCD may have unique neuropsychological deficits suggestive of discrete but overlapping neuroanatomical regions for individual symptom dimensions. Overall, neuropsychological deficits further support the role of frontostriatal circuits in the neurobiology of OCD. In addition, emerging literature also suggests the important role of other areas, in particular parietal cortex. Preliminary evidence suggests the possible role of neuropsychological deficits to be markers of treatment response but needs to be examined in future. Longitudinal studies with examination of patients at different time points and examination of their potential utility as predictors of treatment response are needed in future.

Genetics of obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) has been seen to run in families and genetics help to understand its heritability. In this review, we summarize older studies which focused on establishing the familial nature of OCD, including its various dimensions of symptoms, and we focus on recent findings from studies using both the candidate gene approach and genome-wide association study (GWAS) approach. The family studies and twin studies establish the heritability of OCD. Candidate gene approaches have implicated genes in the serotonergic, glutamatergic, and dopaminergic pathways. GWAS has not produced significant results possibly due to the small sample size. Newer techniques such as gene expression studies in brain tissue, stem cell technology, and epigenetic studies may shed more light on the complex genetic basis of OCD.

Systematic review of co-occurring OCD and TD: Evidence for a tic-related OCD subtype?

OBJECTIVE

The aim of this review is to summarize the current knowledge of associated features of co-occurring obsessive-compulsive disorder (OCD) and tic disorders (TD) and to critically evaluate hypotheses regarding the nature of their comorbidity.

METHOD

We conducted a systematic review following PRISMA guidelines. To this aim, the PubMed, PsychInfo and ISI Web of Knowledge databases were searched up to August 30, 2018. For gender and age-of-onset we additionally conducted meta-analyses.

RESULTS

One hundred eighty-nine studies met inclusion criteria. We substantiate some acknowledged features and report evidence for differential biological mechanisms and treatment response. In general, studies were of limited methodological quality.

CONCLUSIONS

Several specific features are reliable associated with co-occurring OCD + TD. The field lacks methodological sound studies. The review found evidence against and in favor for different hypotheses regarding the nature of comorbidity of OCD and TD. This could indicate the existence of a stepwise model of co-morbidity, or could be an artefact of the low methodological quality of studies.

Genetic susceptibility in obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is present in 1.5-2.5% of the population and can result in substantial lifelong disability. It is characterized by intrusive thoughts, sensations, and urges and by repetitive behaviors that are difficult to control despite, in most cases, preserved insight as to their excessive or irrational nature. The causes and underlying pathophysiology of OCD are not well understood, which has limited the development of new treatments and interventions. Despite evidence for a substantial genetic contribution to disease risk, identification and replication of genetic variants associated with OCD have been challenging. Decades of candidate gene association studies have provided little insight. They are now being supplanted by modern genomewide approaches to discover both common and rare sequence and structural variants. Studies to date suggest potential novel therapeutic avenues such as modulators of glutamatergic and immune pathways; however, individual genetic findings are not yet statistically robust or replicated. Further efforts are clearly needed to identify specific risk variants and to confirm vulnerable pathways by studying much larger cohorts of patients with comprehensive variant discovery approaches. Mouse knockout models have already made notable inroads into our understanding of OCD pathology; their utility will only increase as specific risk alleles are identified.

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.

Impaired planning in patients with obsessive-compulsive disorder and unaffected first-degree relatives: Evidence for a cognitive endophenotype

Patients with obsessive-compulsive disorder (OCD) show deficient planning capacity in the Tower of London (TOL) problem solving task. Preliminary evidence for similar deficits in unaffected first-degree relatives suggests that impaired planning may constitute an endophenotype of OCD. However, results on this issue are inconsistent, possibly owing to small sample sizes and variability in problem structure across TOL tasks. Here, we adopted a computerized version of the TOL task featuring a 2 × 2 factorial design (high/low search depth × full/partial tower goal state) and examined a well-characterized sample of n = 72 OCD patients, n = 76 unaffected first-degree relatives and n = 102 healthy comparison subjects. Both OCD patients and relatives exhibited significantly less accurate problem solving than controls. Search depth, goal hierarchy, or the number of minimum moves did not moderate these group differences. Medication, OCD symptoms, and depressive comorbidity did not affect TOL performance in patients, suggesting a state-independent effect. In conclusion, we found that OCD patients as well as unaffected first-degree relatives show deficient TOL performance across a range of task conditions, strongly supporting the role of impaired planning as an endophenotype of OCD, and contributing to the growing evidence for fronto-striatal dysfunctions in OCD.

Prevalence of Obsessive-Compulsive Spectrum Disorders in Obsessive-Compulsive Disorder

INTRODUCTION

There is growing awareness of the heterogeneity of obsessive-compulsive disorder (OCD) and of the multiple systems involved in its pathogenesis. Identification of obsessive-compulsive spectrum disorders (OCSDs) may have important implications in the management and prognosis of OCD, but there is a paucity of research in the domain of identification of OCSD in probands with OCD. There are few studies that have examined OCSD in the first-degree relatives (FDR) of OCD patients, some of these were not controlled, and these studies have no final agreements over outcomes, and therefore, this area needs to be further explored.

OBJECTIVES

The objective of this study was to assess the prevalence of OCSDs in OCD probands; and its relationship to sociodemographic and clinical variables, comparing each aspect by a control group of schizophrenia probands.

MATERIALS AND METHODS

Sixty patients each of OCD and schizophrenia, diagnosed by the Diagnostic and Statistical Manual of Mental Disorders IV Text Revision,[1] above 18 years of age and giving informed consent, were interviewed using the Structured Clinical Interview for OCSD, Yale-Brown Obsessive-Compulsive Rating Scale, Hamilton Rating Scale for Depression, and Hamilton Rating Scale for Anxiety.

RESULTS

In OCD group, 22 OCSDs were found in 11 subjects whereas in schizophrenia group, 2 OCSDs (self-injury) were found in two probands. When the two groups were compared in terms of individual OCSDs, there was no significant difference between them. However, when the comparison was made taking into account all OCSDs taken together, it was significantly higher (P = 0.016) in the OCD group compared to the schizophrenia group.

CONCLUSION

OCSDs were significantly more in OCD probands as compared to schizophrenia probands. This suggests a familial aggregation of these disorders.

Revealing the complex genetic architecture of obsessive-compulsive disorder using meta-analysis

Two obsessive-compulsive disorder (OCD) genome-wide association studies (GWASs) have been published by independent OCD consortia, the International Obsessive-Compulsive Disorder Foundation Genetics Collaborative (IOCDF-GC) and the OCD Collaborative Genetics Association Study (OCGAS), but many of the top-ranked signals were supported in only one study. We therefore conducted a meta-analysis from the two consortia, investigating a total of 2688 individuals of European ancestry with OCD and 7037 genomically matched controls. No single-nucleotide polymorphisms (SNPs) reached genome-wide significance. However, in comparison with the two individual GWASs, the distribution of P-values shifted toward significance. The top haplotypic blocks were tagged with rs4733767 (P=7.1 × 10^-7; odds ratio (OR)=1.21; confidence interval (CI): 1.12-1.31, CASC8/CASC11), rs1030757 (P=1.1 × 10^-6; OR=1.18; CI: 1.10-1.26, GRID2) and rs12504244 (P=1.6 × 10^-6; OR=1.18; CI: 1.11-1.27, KIT). Variants located in or near the genes ASB13, RSPO4, DLGAP1, PTPRD, GRIK2, FAIM2 and CDH20, identified in linkage peaks and the original GWASs, were among the top signals. Polygenic risk scores for each individual study predicted case-control status in the other by explaining 0.9% (P=0.003) and 0.3% (P=0.0009) of the phenotypic variance in OCGAS and the European IOCDF-GC target samples, respectively. The common SNP heritability in the combined OCGAS and IOCDF-GC sample was estimated to be 0.28 (s.e.=0.04). Strikingly, ∼65% of the SNP-based heritability in the OCGAS sample was accounted for by SNPs with minor allele frequencies of ⩾40%. This joint analysis constituting the largest single OCD genome-wide study to date represents a major integrative step in elucidating the genetic causes of OCD.

Clinical profile and outcome in a large sample of children and adolescents with obsessive-compulsive disorder: A chart review from a tertiary care center in India

BACKGROUND

Obsessive-compulsive disorder (OCD) is a common psychiatric illness in children and adolescents. Till date, the sample sizes in the Indian studies have been relatively small.

METHODOLOGY

The present study is a retrospective chart review of a large sample of children and adolescents diagnosed with OCD in a tertiary care center.

OBJECTIVES

The objectives of this study were to characterize the clinical profile and to evaluate outcome of OCD in children and adolescents.

RESULTS

Fear of contamination and washing/cleaning compulsions were the most common presenting symptoms. Most of the patients were male with two-thirds having a comorbid disorder. Major depressive disorder was the most common comorbid disorder. The rates of attention deficit hyperactivity disorder, disruptive behavioral disorders, and tic disorders were low when compared to Western studies. One-third of the patients received adequate trial of serotonin reuptake inhibitors and 36% received cognitive behavior therapy. Fifty-four percent of patients had a poor outcome with hospitalization, longer duration of illness, earlier onset of OC symptoms, and family history of OCD being the predictors of poor outcome.

CONCLUSION

The present study of a large sample of patients with juvenile OCD highlights the low rate of comorbid disruptive behavior disorders as reported in the earlier Indian studies and a favorable short-term outcome in approximately 56% of the patients.

A systematic review of the clinical effectiveness and cost-effectiveness of pharmacological and psychological interventions for the management of obsessive-compulsive disorder in children/adolescents and adults

BACKGROUND

Obsessive-compulsive disorder (OCD) is a relatively common and disabling condition.

OBJECTIVES

To determine the clinical effectiveness, acceptability and cost-effectiveness of pharmacological and psychological interventions for the treatment of OCD in children, adolescents and adults.

DATA SOURCES

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Trials Registers, which includes trials from routine searches of all the major databases. Searches were conducted from inception to 31 December 2014.

REVIEW METHODS

We undertook a systematic review and network meta-analysis (NMA) of the clinical effectiveness and acceptability of available treatments. Outcomes for effectiveness included mean differences in the total scores of the Yale-Brown Obsessive-Compulsive Scale or its children's version and total dropouts for acceptability. For the cost-effectiveness analysis, we developed a probabilistic model informed by the results of the NMA. All analyses were performed using OpenBUGS version 3.2.3 (members of OpenBUGS Project Management Group; see www.openbugs.net ).

RESULTS

We included 86 randomised controlled trials (RCTs) in our systematic review. In the NMA we included 71 RCTs (54 in adults and 17 in children and adolescents) for effectiveness and 71 for acceptability (53 in adults and 18 in children and adolescents), comprising 7643 and 7942 randomised patients available for analysis, respectively. In general, the studies were of medium quality. The results of the NMA showed that in adults all selective serotonin reuptake inhibitors (SSRIs) and clomipramine had greater effects than drug placebo. There were no differences between SSRIs, and a trend for clomipramine to be more effective did not reach statistical significance. All active psychological therapies had greater effects than drug placebo. Behavioural therapy (BT) and cognitive therapy (CT) had greater effects than psychological placebo, but cognitive-behavioural therapy (CBT) did not. BT and CT, but not CBT, had greater effects than medications, but there are considerable uncertainty and methodological limitations that should be taken into account. In children and adolescents, CBT and BT had greater effects than drug placebo, but differences compared with psychological placebo did not reach statistical significance. SSRIs as a class showed a trend for superiority over drug placebo, but the difference did not reach statistical significance. However, the superiority of some individual drugs (fluoxetine, sertraline) was marginally statistically significant. Regarding acceptability, all interventions except clomipramine had good tolerability. In adults, CT and BT had the highest probability of being most cost-effective at conventional National Institute for Health and Care Excellence thresholds. In children and adolescents, CBT or CBT combined with a SSRI were more likely to be cost-effective. The results are uncertain and sensitive to assumptions about treatment effect and the exclusion of trials at high risk of bias.

LIMITATIONS

The majority of psychological trials included patients who were taking medications. There were few studies in children and adolescents.

CONCLUSIONS

In adults, psychological interventions, clomipramine, SSRIs or combinations of these are all effective, whereas in children and adolescents, psychological interventions, either as monotherapy or combined with specific SSRIs, were more likely to be effective. Future RCTs should improve their design, in particular for psychotherapy or combined interventions.

STUDY REGISTRATION

The study is registered as PROSPERO CRD42012002441.

FUNDING DETAILS

The National Institute for Health Research Health Technology Assessment programme.