Towards a definitive symptom structure of obsessive-compulsive disorder: a factor and network analysis of 87 distinct symptoms in 1366 individuals

A network analysis of body dysmorphic and obsessive-compulsive symptoms among individuals with and without exposure to trauma

BACKGROUND

BDD and OCD symptoms often co-occur, but the associations between specific symptoms remain unclear. Furthermore, current research suggests that the clinical presentation of emotional disorders can differ in individuals who self-report exposure to trauma, but it is unclear whether this extends to BDD and OCD. The current study aimed to: (a) investigate associations between individual OCD and BDD symptoms and (b) determine whether symptom networks differ in those with self-reported trauma compared to those without self-reported trauma.

METHODS

Participants (N = 3127) were drawn from the Genetic Links to Anxiety and Depression (GLAD) Study and had completed validated self-reported questionnaires to assess BDD and OCD symptoms, and childhood and adulthood experiences of trauma. Network analysis was used to investigate associations between seven BDD symptoms and six OCD symptom domains. Networks of reporters and non-reporters of lifetime trauma were compared using the network comparison test.

RESULTS

BDD and OCD symptoms clustered distinctively with some bridging associations between them. The strongest bridging edges highlighted an association between three core BDD symptoms and the OCD domain of obsessional thoughts. BDD and OCD networks of reporters and non-reporters of lifetime trauma did not differ.

LIMITATIONS

Cross-sectional design, meaning causality cannot be inferred.

CONCLUSIONS

The findings suggest that BDD and OCD symptoms cluster distinctively, with some bridging associations between core BDD symptoms and obsessional thoughts. Future research is needed to understand the mechanisms underpinning this relationship.

Movement Toward Dimensional Symptom Models of Comorbid Obsessive-Compulsive Disorder and Eating Disorders

Obsessive-compulsive disorder (OCD) and eating disorders (EDs) are highly comorbid. Despite the high comorbidity, there is little understanding of why these disorders coexist and even less research on how to best treat this co-occurrence. In this article, we review the literature on comorbid OCD-ED and discuss potential underlying shared mechanisms, including anxiety/avoidance, perfectionism, intolerance of uncertainty, habit formation, disgust, shame and guilt, rumination, metacognitive beliefs, and shared biological characteristics. We then discuss prior models of OCD-ED comorbidity and shift the perspective from latent or categorical models to dimensional symptom models (e.g., network models). We describe how dimensional symptom models could advance the conceptualization, treatment, and prevention of comorbid OCD-ED. Next, we discuss how idiographic (one-person) symptom models could advance personalized treatment and provide a treatment example. Finally, we discuss future research needed to advance the field and improve treatment outcomes.

Network Analysis of Premonitory Urges, Tic Symptoms, Obsessive-Compulsive Symptoms, and Quality of Life in Drug-Naïve Children and Adolescents with Tic Disorder

Premonitory urges (PU) in tic disorder (TD) are recognized as a crucial factor influencing tic symptoms and overall well-being. This study employs network analysis to explore the intricate relationships among PU, tic symptoms, obsessive-compulsive symptoms (OCS), and quality of life (QoL) in drug-naïve children and adolescents with TD. Participants were drug-naïve TD patients aged 6 to 16 years. All participants consented to undergo multiple accessments, including the Yale Global Tic Severity Scale (YGTSS), Premonitory Urge to Tic Scale (PUTS), Gilles de la Tourette-Quality of Life Scale (GTS-QOL), Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS), and Obsessive-Compulsive Inventory-Revised (OCI-R). Network analysis was conducted using the R-package qgraph. Based on a sample of 344 TD patients, robust associations were identified between PU and tic symptoms, OCS, and QoL deficits. Centrality analysis identified ordering symptoms and obsessive thoughts as key nodes. Notable cross-scale associations were observed, such as the connections between PU and checking symptoms, as well as PU and obsessive thoughts. Bridge centrality analysis revealed that obsessive thoughts were identified as the strongest bridge symptom. PU was indirectly related to QoL in individuals with TD, while OCS exerted a direct association. Our study underscores the role of OCS in tic-related symptoms among individuals with TD. Highlighting the significant associations between PU and OCS, it emphasizes the necessity for targeted interventions to improve overall well-being.

Precision Psychiatry for Obsessive-Compulsive Disorder: Clinical Applications of Deep Learning Architectures

Obsessive-compulsive disorder (OCD) is a complex psychiatric condition characterized by significant heterogeneity in symptomatology and treatment response. Advances in neuroimaging, EEG, and other multimodal datasets have created opportunities to identify biomarkers and predict outcomes, yet traditional statistical methods often fall short in analyzing such high-dimensional data. Deep learning (DL) offers powerful tools for addressing these challenges by leveraging architectures capable of classification, prediction, and data generation. This brief review provides an overview of five key DL architectures-feedforward neural networks, convolutional neural networks, recurrent neural networks, generative adversarial networks, and transformers-and their applications in OCD research and clinical practice. We highlight how these models have been used to identify the neural predictors of treatment response, diagnose and classify OCD, and advance precision psychiatry. We conclude by discussing the clinical implementation of DL, summarizing its advances and promises in OCD, and underscoring key challenges for the field.

No Impaired Inhibition of Stimulus-Driven Behavior in Pediatric Obsessive-Compulsive Disorder: a Partial Test of the Habit Formation Model

The mechanisms that underlie obsessive-compulsive disorder (OCD) are elusive. The habit formation model of OCD postulates that compulsions arise from an imbalance between goal-directed and habit formation systems, stemming from impaired inhibition of stimulus-driven actions. Few studies have examined the core tenets of the habit formation model in pediatric OCD. We administered the object-interference task, which assesses the ability to inhibit stimulus-driven behavior, to 67 youths with OCD, 43 youths with an anxiety disorder (and no OCD), and 48 youths without any mental disorder. Impaired inhibition of stimulus-driven behavior was calculated by comparing response times to neutral non-nameable objects, neutral nameable objects, distress-eliciting objects, and incompleteness-eliciting objects. Youths with OCD did not differ significantly from youths with anxiety disorders and the non-clinical group on any response cost measure. All groups showed small response costs in relation to all three categories of non-neutral objects, with the clearest cost emerging in relation to distress-eliciting objects. Individual differences in response cost were not significantly correlated with any interview- or self-rated measure of OCD severity. Using the object-interference task, no evidence was found for impaired inhibition of stimulus-driven behavior in youths with OCD. We explore several possible interpretations of this result, including limitations of the task itself, the broader constraints of experimental methods in detecting such mechanisms, and the possibility that an imbalance between goal-directed and habit systems may not be a fundamental feature of pediatric OCD.

No Biased Attention to Threat, Incompleteness, and Disgust in Youth with OCD and Anxiety Disorders

Obsessive-compulsive disorder (OCD) and anxiety disorders are early-onset mental disorders characterized by selective attention and strong emotional reactions. Attentional bias has been proposed to play a role in the development, onset, and maintenance of the disorders, but few studies have included youth with mental disorders, and no study has included more than one clinical group, making it unclear whether biased attention is disorder-specific or transdiagnostic in nature. In the present study, 65 youths with OCD (Mage = 13.6 [2.4], 57% girls), 52 youths with anxiety disorders (Mage = 14.5 [2.6] 83% girls), and 45 youths without a psychiatric disorder (Mage = 13.9 [3.1], 67% girls) completed a modified dot-probe task that included threat, incompleteness, and disgust cues. Contrary to our hypotheses, no group exhibited any attentional bias to any emotional cue, no group differences were present, and individual differences in attentional bias were not associated with individual differences in any symptom type. Disgust cues produced slower response times compared to the other emotional cues, but this effect was consistent across all type of trials and present in all three groups. In this study, no support for biased attention in treatment-seeking youth with OCD or anxiety disorders was found, which is in line with recent findings in adults using the dot-probe task. As attentional processes are clearly implicated in the clinical manifestation of these disorders, future research should try to better operationalize and measure relevant processes.

The relationship between sensory phenomena and interoception across the obsessive-compulsive spectrum: a systematic review

BACKGROUND

Uncomfortable sensations preceding repetitive behaviours, known as sensory phenomena, have been documented across the obsessive-compulsive spectrum. Indirect evidence suggests altered interoception may play a role in these shared experiences of sensory phenomena; however, research explicitly measuring this relationship is limited. The current systematic review aimed to establish the nature of sensory phenomena and interoception in obsessive-compulsive and related disorders (OCRDs) and tic disorders as potential maintaining factors of these disorders.

METHODS

PsycINFO, PubMed, and Scopus databases were searched from 2007 to April 2024, yielding 65 studies.

RESULTS

While the majority of studies presented low risk of bias, significant overlap and ambiguity characterised the measurement and conceptualisation of sensory phenomena and interoception. Overall, higher sensory phenomena was associated with greater symptom severity in several obsessive-compulsive spectrum disorders. Obsessive-compulsive disorder and tic disorder samples were characterised by lower interoceptive accuracy, with mixed findings on interoceptive sensibility. Some limited research emerged suggesting altered interoceptive abilities may be associated with greater sensory phenomena in obsessive-compulsive disorder and tic disorders.

CONCLUSIONS

Sensory phenomena are experienced across the obsessive-compulsive spectrum. Future research should explore interoceptive abilities across the OCRDs, and build upon evidence supporting a relationship between sensory phenomena and interoception in OCD and tic disorders.

TRIAL REGISTRATION

CRD42023422817.

Phenomenology of repetitive and restrictive behaviors and sensory phenomena in neurodevelopmental disorders: an exploratory study

BACKGROUND

Repetitive and restrictive behaviors (RRB) include simple motor stereotypes, tics and complex ritualized and rigid behaviors that are core symptoms in neurodevelopmental disorders such as obsessive-compulsive disorder (OCD), Tourette syndrome (TS) or autism spectrum disorder (ASD). Sensory phenomena (SP) are uncomfortable feelings, including bodily sensations, sense of inner tension, "just-right" perceptions, feelings of incompleteness, or "urge-only" phenomena, which have been described to precede, trigger, or accompany RRB. In such clinical contexts RRB and SP may be considered common variables that affect multiple aspects of daily functioning and are treatment targets.

OBJECTIVE

This study aims to further understand RRB and SP phenomenology in children and adolescents diagnosed with OCD, TS or ASD and identify whether specific RRB or SP can distinguish these groups.

METHODS

We assessed RRB and SP in participants aged between 6 and 17 with a main diagnosis of OCD (n = 23), TS (n = 19), or ASD (n = 21) with the Repetitive Behavior Scale-Revised (RBS-R) and The University of Sao Paulo-Sensory Phenomena Scale (USP-SPS).

RESULTS

The RBS-R mean was 17.3 ± 14.9 with no group differences for total RBS-R symptom severity, except for the routine subscale (OCD > ASD, p = 0.03). Ninety percent of participants showed at least one type of SP on the USP-SPS with a mean total severity of 5.3 ± 3.8, with no statistical differences between groups. The most frequent SP subtype was physical sensations (68.4%).

CONCLUSION

RRB and SP are transdiagnostic features in neurodevelopmental disorders and the RBS-R and the USP-SPS might be useful in their assessment and treatment plan.

The association between salivary oxytocin, age, and puberty in children with and without OCD

The oxytocin system has been thought to contribute to obsessive-compulsive disorder (OCD). Few studies, only involving adults, have investigated this hypothesis and have found inconsistent results regarding oxytocin system activity and OCD. We investigated whether salivary oxytocin concentrations differed between children and adolescents with and without OCD and qualified our comparative analysis by investigating the possible covariates age, pubertal stage, and sex. Participants included 113 children and adolescents (8-17 years) with OCD and 88 children and adolescents without any previous or current psychiatric disorder and their parents (254 parents included). Salivary oxytocin concentrations were measured in children and parents with enzyme-linked immunosorbent assay (ELISA). Statistical analyses were performed using frequentist and Bayesian approaches. We found no evidence of a difference in mean salivary oxytocin concentrations between children and adolescents with and without OCD. Bayesian analysis indicated anecdotal to moderate support for the null hypothesis. We found an association between oxytocin and age and between oxytocin and pubertal stage, which by visual inspection of plots and post-hoc tests indicated nonlinear relationships. We found no association between oxytocin concentration and sex. Our findings do not suggest elevated oxytocin concentrations in pediatric OCD. Nonlinear changes in oxytocin across development show the importance of accounting for hormonal and behavioral changes during puberty.

Longitudinal relationship between oppositional defiant disorder symptoms and attention-deficit/hyperactivity disorder symptoms in Chinese children: insights from cross-lagged panel network analyses

Oppositional defiant disorder (ODD) and attention-deficit/hyperactivity disorder (ADHD) are two of the most common childhood mental disorders, and they have substantial comorbidity. The developmental precursor model has long been widely used to explain the mechanisms of comorbidity between ODD and ADHD, however whether it is equally effective at the symptomatic level is unclear. Therefore, this study aimed to (a) examine the stability of the ODD and ADHD comorbidity network in a longitudinal sample of high-risk children in China; and (b) examine the longitudinal relationship between the ODD and ADHD symptom networks based on a developmental precursor model. Two hundred sixty-three Chinese children aged 6 to 13 years with ODD and/or ADHD were assessed for symptoms of ODD and ADHD in two surveys conducted 1 year apart. We used data from these two time points to construct two cross-sectional networks and a cross-lagged panel network (CLPN) to explore the symptom network for comorbidity of ODD and ADHD. The analysis shows that: (1) the two cross-sectional networks are highly similar in terms of structure, existence of edges, centrality estimates, and the invariance test shows that there is no significant difference between them. The symptoms "follow through", "interrupts/intrudes", "difficulty playing quietly" and "concentration" had the highest expected influence centrality at both time points. (2) Combined with the results of the cross-sectional and cross-lagged networks, we found that "annoy" and "blame" are potential bridge symptoms between the ODD and ADHD symptom networks. The symptom "annoy" forms a reciprocal predictive relationship with "interrupts/intrudes", while "blame" unidirectionally predicts "close attention". In addition, we found that "vindictive" predicted numerous ADHD symptoms, whereas "angry" was predicted by numerous ADHD symptoms. The findings emphasize the broad predictive relationship between ODD and ADHD symptoms with each other, and that ODD symptoms may lead to activation of the ADHD symptom network and vice versa. These findings suggest that the developmental precursor model at the symptom level may partially explain the comorbidity mechanisms of ODD and ADHD, and future studies should further investigate the underlying multiple mechanisms.

An investigation of the experience of control through the sense of agency in people with obsessive-compulsive disorder: a review and meta-analysis

The construct of sense of agency (SoA) has proven useful for understanding mechanisms underlying obsessive-compulsive disorder (OCD) phenomenology, especially in explaining the apparent dissociation in OCD between actual and perceived control over one's actions. Paradoxically, people with OCD appear to experience both diminished SoA (feeling unable to control their actions) and inflated SoA (having "magical" control over events). The present review investigated the extent to which the SoA is distorted in OCD, in terms of both implicit (ie, inferred from correlates and outcomes of voluntary actions) and explicit (ie, subjective judgment of one's control over an outcome) measures of SoA. Our search resulted in 15 studies that met the criteria for inclusion in a meta-analysis, where we also examined the potential moderating effects of the type of measure (explicit versus implicit) and of the actual control participants had over the outcome. We found that participants with OCD or with high levels of OCD symptoms show lower implicit measures of SoA and at the same time tend to overestimate their control in situations where they do not actually have it. Together, these findings support the hypothesized dissociation in OCD between actual and perceived control over one's actions.

Mindfulness as a therapeutic option for obsessive-compulsive disorder

INTRODUCTION

Obsessive-compulsive disorder (OCD) is a prevalent mental health issue characterized by intrusive thoughts (obsessions) and repetitive behaviors (compulsions) that can cause significant life impairment. Despite cognitive-behavioral therapy (CBT) being the most effective treatment, some individuals experience insufficient symptom reduction or relapse.

AREAS COVERED

This special report explores the potential of mindfulness-based interventions as complementary treatments for OCD, examining the specific techniques used and their practical application. In the initial section, the authors examine ten randomized control trial studies included in the meta-analysis conducted by Chien et al. (2022), demonstrating the effectiveness of mindfulness interventions. The authors focus on elucidating the specific mindfulness techniques used in these studies. Then, the authors discuss the integration of these mindfulness strategies into CBT, focusing on enhancing emotional regulation, cognitive flexibility, and acceptance of intrusive thoughts.

EXPERT OPINION

While mindful based interventions (MBIs) show promise as adjunctive treatments for OCD, variability in OCD symptoms and treatment responses necessitate individualized therapeutic approaches. Further research is required to refine mindfulness-based techniques and optimize their effectiveness. Incorporating MBIs into standard CBT protocols may improve outcomes for patients with persistent OCD symptoms.

Resting-state functional connectivity of amygdala subregions across different symptom subtypes of obsessive-compulsive disorder patients

AIM

Obsessive-compulsive disorder (OCD) is a heterogeneous condition characterized by distinct symptom subtypes, each with varying pathophysiologies and treatment responses. Recent research has highlighted the role of the amygdala, a brain region that is central to emotion processing, in these variations. However, the role of amygdala subregions with distinct functions has not yet been fully elucidated. In this study, we aimed to clarify the biological mechanisms underlying OCD subtype heterogeneity by investigating the functional connectivity (FC) of amygdala subregions across distinct OCD symptom subtypes.

METHODS

Resting-state functional magnetic resonance images were obtained from 107 medication-free OCD patients and 110 healthy controls (HCs). Using centromedial, basolateral, and superficial subregions of the bilateral amygdala as seed regions, whole-brain FC was compared between OCD patients and HCs and among patients with different OCD symptom subtypes, which included contamination fear and washing, obsessive (i.e., harm due to injury, aggression, sexual, and religious), and compulsive (i.e., symmetry, ordering, counting, and checking) subtypes.

RESULTS

Compared to HCs, compulsive-type OCD patients exhibited hypoconnectivity between the left centromedial amygdala (CMA) and bilateral superior frontal gyri. Compared with patients with contamination fear and washing OCD subtypes, patients with compulsive-type OCD showed hypoconnectivity between the left CMA and left frontal cortex.

CONCLUSIONS

CMA-frontal cortex hypoconnectivity may contribute to the compulsive presentation of OCD through impaired control of behavioral responses to negative emotions. Our findings underscored the potential significance of the distinct neural underpinnings of different OCD manifestations, which could pave the way for more targeted treatment strategies in the future.

Co-occurring PTSD in intensive OCD treatment: Impact on treatment trajectory vs. response

BACKGROUND

Obsessive-compulsive disorder (OCD) and co-occurring posttraumatic stress disorder (PTSD) is associated with more severe and chronic OCD. However, findings regarding treatment effectiveness of cognitive behavioral treatment (CBT) with exposure and response prevention (ERP) with this comorbidity are mixed. Research aimed at understanding the precise barriers to OCD treatment effectiveness for individuals with co-occurring PTSD may help elucidate unique treatment needs.

METHODS

The current study used linear regression and latent growth curve analysis comparing treatment response and trajectory from patients with OCD (n = 3083, 94.2 %) and OCD + PTSD (n = 191, 5.2 %) who received CBT with ERP in two major intensive OCD treatment programs.

RESULTS

Although patients with OCD + PTSD evidenced similar trajectories of overall severity change, patients at one site required nearly 11 additional treatment days to achieve comparable reduction in OCD severity. Further, at the dimensional level, those with OCD + PTSD had poorer treatment response for unacceptable thoughts and symmetry symptoms. The moderate effect for unacceptable thoughts, indicating the widest gap in treatment response, suggests these symptoms may be particularly relevant to PTSD.

LIMITATIONS

Findings are limited by a naturalistic treatment sample with variation in treatment provision.

CONCLUSIONS

Findings emphasize caution in using a one-size-fits-all approach for patients with co-occurring OCD + PTSD within intensive OCD treatment programs, as broadly defined outcomes (e.g., reduction in overall severity) may not translate to reduction in the nuanced symptom dimensions likely to intersect with trauma. Unacceptable thoughts and symmetry symptoms, when co-occurring with PTSD, may require a trauma-focused treatment approach within intensive OCD treatment.

From compulsivity to compulsion: the neural basis of compulsive disorders

Compulsive behaviour, an apparently irrational perseveration in often maladaptive acts, is a potential transdiagnostic symptom of several neuropsychiatric disorders, including obsessive-compulsive disorder and addiction, and may reflect the severe manifestation of a dimensional trait termed compulsivity. In this Review, we examine the psychological basis of compulsions and compulsivity and their underlying neural circuitry using evidence from human neuroimaging and animal models. Several main elements of this circuitry are identified, focused on fronto-striatal systems implicated in goal-directed behaviour and habits. These systems include the orbitofrontal, prefrontal, anterior cingulate and insular cortices and their connections with the basal ganglia as well as sensoriomotor and parietal cortices and cerebellum. We also consider the implications for future classification of impulsive-compulsive disorders and their treatment.

Comparative efficacy of repetitive transcranial magnetic stimulation protocols for obsessive-compulsive disorder: A network meta-analysis

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has been found to be helpful for the treatment of obsessive-compulsive disorder (OCD). However, the relative efficacy of different rTMS protocols is unclear.

OBJECTIVE

To conduct a systematic review and network meta-analysis (NMA) of published literature to compare the relative efficacy of different rTMS protocols for decreasing Yale-Brown Obsessive Compulsive Severity (Y-BOCS) scores in patients with OCD.

METHOD

Relevant articles published between 1985 to September 2023 were searched from the Cochrane Central Register of Controlled Trials, PubMed and PsycInfo. Double or single-blinded randomized controlled studies conducted on patients with OCD comparing an active rTMS protocol with either another active or sham rTMS protocol were included. Network meta-analysis (NMA) was conducted using a frequentist approach. Standardized mean difference (SMD) of change in Y-BOCS scores was calculated employing Hedge's g. Pairwise meta-analysis using random effects model was conducted which was extended to the NMA using restricted maximum likelihood estimation procedure. Surface under the cumulative ranking (SUCRA) probabilities were used to rank the interventions.

RESULTS

Excitatory rTMS of the bilateral dorsolateral prefrontal cortex (DLPFC), inhibitory rTMS of right DLPFC, inhibitory as well as excitatory rTMS of bilateral medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC) and inhibitory rTMS of bilateral supplementary motor area (SMA) were superior to sham stimulation. The DLPFC and mPFC/ACC protocols had a higher probability of being among the top-ranked interventions. The majority of studies had a modest sample size and at least some concerns in the risk of bias assessment.

CONCLUSION

rTMS targeting either the medial or lateral prefrontal cortices is a promising intervention for resistant OCD. There is a need to confirm these findings in large systematic studies.

A Psychometric Evaluation of the Expanded Version of the Inventory of Depression and Anxiety Symptoms (IDAS-II) in Children and Adolescents

The expanded version of the Inventory of Depression and Anxiety Symptoms (IDAS-II) is a self-report measure of 18 empirically derived internalizing symptom dimensions. The measure has shown good psychometric properties in adults but has never been evaluated in children and adolescents. A Swedish version of the IDAS-II was administered to 633 children and adolescents (Mage =16.6 [SD = 2.0]) and 203 adults (Mage = 35.4 [SD = 12.1]). The model/data fit of the 18-factor structure was excellent in both samples and measurement invariance across age groups was supported. All scales showed good to excellent internal consistency and psychometric properties replicated in the younger youth sample (< 16 years). Among youth, good convergent validity was established for all scales and divergent validity for most scales. The IDAS-II was better at identifying youth with current mental health problems than an internationally recommended scale of internalizing symptoms. In conclusion, the IDAS-II shows promise as a measure of internalizing symptoms in youth.

The clinical presentation of major depressive disorder in youth with co-occurring obsessive-compulsive disorder

BACKGROUND

Major depressive disorder (MDD) is common in youth and among the most frequent comorbid disorders in pediatric obsessive-compulsive disorder (OCD), but it is unclear whether the presence of OCD affects the symptom presentation of MDD in youth.

METHODS

A sample of youth with OCD and MDD (n = 124) and a sample of youth with MDD but no OCD (n = 673) completed the Patient Health Questionnaire for Adolescents (PHQ-A). The overall and symptom-level presentation of MDD were examined using group comparisons and network analysis.

RESULTS

Youth with MDD and OCD, compared to those with MDD and no OCD, had more severe MDD (Cohen's d = 0.39) and more reported moderate to severe depression (75 % vs 61 %). When accounting for demographic variables and the overall severity of MDD, those with comorbid OCD reported lower levels of anhedonia and more severe difficulties with psychomotor retardation/agitation. No significant differences in the interconnections among symptoms emerged.

LIMITATIONS

Data were cross-sectional and self-reported, gold standard diagnostic tools were not used to assess OCD, and the sample size for the group with MDD and OCD was relatively small yielding low statistical power for network analysis.

CONCLUSIONS

Youth with MDD and OCD have more severe MDD than those with MDD and no OCD and they experience more psychomotor issues and less anhedonia, which may relate to the behavioral activation characteristic of OCD.

Temperament Traits in Pediatric Obsessive-Compulsive Disorder in Relation to Tourette Syndrome and Attention-Deficit Hyperactivity Disorder

INTRODUCTION

Pediatric obsessive-compulsive disorder (OCD), attention-deficit hyperactivity disorder (ADHD), and Tourette syndrome (TS) are often concurrent. This study explores the temperament profile of complex OCD phenotypes.

METHODS

A clinical registry recorded demographic data, psychiatric diagnoses, and temperament traits, including novelty seeking (exploratory behaviors), harm avoidance (fear of uncertainty), reward dependence (sentimentality), and persistence (perseverance). Temperament data were accrued from the Junior Temperament and Character Inventory (JTCI). Participants were divided into (1) OCD only; (2) OCD+ADHD or TS; and (3) OCD+ADHD+TS to compare temperament.

RESULTS

Participants include 126 youths with OCD (61.9% male, 88.9% white) between the ages 6 and 18 years (12.7 ± 3.1). Among the three groups, the complex neurodevelopmental disorder group OCD+ADHD+TS expresses the highest novelty seeking and lowest persistence. Harm avoidance is increased in all groups compared to reference controls, irrespective of concurrent ADHD or TS. For the OCD+ADHD+TS group, contamination and washing symptoms have higher novelty seeking (p < 0.01), while counting and ordering have lower novelty seeking (p < 0.05). Harm avoidance is increased with aggressive, somatic, and checking symptoms in OCD only (p < 0.01), while persistence is increased with repeating and counting symptoms in the comorbid groups (OCD+ADHD or TS, OCD+ADHD+TS).

DISCUSSION/CONCLUSION

The complex subtype, OCD+ADHD+TS, is associated with high novelty seeking and low persistence, while high harm avoidance is linked to pediatric OCD irrespective of ADHD or TS co-occurrence. In sum, pediatric OCD with ADHD and TS confers a unique temperament profile, further refining complex phenotypes of pediatric OCD for future research.

In Search of Conceptual Clarity About the Structure of Psychopathic Traits in Children: A Network-Based Proposal

Psychopathic traits in childhood have been revealed as potential identifiers of risk, being predictive of later forms of behavioral maladjustment. Yet, it is still under debate how psychopathic traits in children should be best conceptualized and which are the core dimensions for construct definition and prediction. The present study aims to examine the structure of psychopathic traits in childhood, and its predictive value, by using a combination of traditional factor analysis and more recent network-based methods. Data on psychopathic traits, as measured by the Child Problematic Traits Inventory (CPTI), were collected in a large sample of children (n = 2454; 48.2% girls), aged 3 to 6 at the onset of the study (Mage = 4.26; SD = 0.91), who were followed-up one and two years later using parent- and teacher-reports. Results showed that psychopathic traits measured via CPTI are best conceptualized as five latent factors encompassing grandiosity, deceitfulness, callousness, impulsivity and need of stimulation, a result that converged across informants and time. Callousness and grandiosity emerged as central traits using network analysis of parent-reports, while deceitfulness was most central using teacher-reports. Finally, callousness, impulsivity and deceitfulness emerged as the best predictors of concurrent, prospective and stable conduct problems. These results provide a refined structure of psychopathic traits in children that better accounts for the core elements of the construct. Additional theoretical and practical implications will be discussed in terms of assessment, diagnostic classification and tailored prevention/intervention.

Excessive Checking in Obsessive-Compulsive Disorder: Neurochemical Correlates Revealed by 7T Magnetic Resonance Spectroscopy

Background

Compulsive checking, a common symptom of obsessive-compulsive disorder (OCD), has been difficult to capture experimentally. Therefore, determination of its neural basis remains challenging despite some evidence suggesting that it is linked to dysfunction of cingulostriatal systems. This study introduces a novel experimental paradigm to measure excessive checking and its neurochemical correlates.

Methods

Thirty-one patients with OCD and 29 healthy volunteers performed a decision-making task requiring them to decide whether 2 perceptually similar visual representations were the same or different under a high-uncertainty condition without feedback. Both groups underwent 7T magnetic resonance spectroscopy scans on the same day. Correlations between out-of-scanner experimental measures of checking and the glutamate/GABA (gamma-aminobutyric acid) ratio in the anterior cingulate cortex, supplementary motor area, and occipital cortex were assessed. Their relationship with subjective ratings of doubt, anxiety, and confidence was also investigated.

Results

Patients with OCD exhibited excessive and dysfunctional checking, which was significantly correlated with changes in the glutamate/GABA ratio within the anterior cingulate cortex. No behavioral/neurochemical relationships were evident for either the supplementary motor area or occipital cortex. The excessive checking observed in patients was negatively correlated with their confidence levels and positively related to doubt, anxiety, and compulsivity traits.

Conclusions

We conclude that experimental measures of excessive and dysfunctional checking in OCD, which have been linked to increased doubt, anxiety, and lack of confidence, are related to an imbalance between excitatory and inhibitory neural activity within the anterior cingulate cortex. This study adds to our understanding of the role of this region in OCD by providing a laboratory model of the possible development of compulsive checking.

Revisiting deficits in threat and safety appraisal in obsessive-compulsive disorder

Current behavioural treatment of obsessive-compulsive disorder (OCD) is informed by fear conditioning and involves iteratively re-evaluating previously threatening stimuli as safe. However, there is limited research investigating the neurobiological response to conditioning and reversal of threatening stimuli in individuals with OCD. A clinical sample of individuals with OCD (N = 45) and matched healthy controls (N = 45) underwent functional magnetic resonance imaging. While in the scanner, participants completed a well-validated fear reversal task and a resting-state scan. We found no evidence for group differences in task-evoked brain activation or functional connectivity in OCD. Multivariate analyses encompassing all participants in the clinical and control groups suggested that subjective appraisal of threatening and safe stimuli were associated with a larger difference in brain activity than the contribution of OCD symptoms. In particular, we observed a brain-behaviour continuum whereby heightened affective appraisal was related to increased bilateral insula activation during the task (r = 0.39, pFWE  = .001). These findings suggest that changes in conditioned threat-related processes may not be a core neurobiological feature of OCD and encourage further research on the role of subjective experience in fear conditioning.

Conceptualising compulsivity through network analysis: A two-sample study

Compulsivity is a transdiagnostic construct crucial to understanding multiple psychiatric conditions and problematic repetitive behaviours. Despite being identified as a clinical- and research-relevant construct, there are limited insights into the internal conceptual structure of compulsivity. To provide a more nuanced understanding of compulsivity, the current study estimated the structure of compulsivity (indexed using the previously validated Cambridge-Chicago Compulsivity Trait Scale, CHI-T) among two large-scale and geographically distinct samples using the network estimation method. The samples consisted of a United Kingdom cohort (n = 122,346, 51.4% female, Mean age = 43.7, SD = 16.5, range = 9-86 years) and a South Africa cohort (n = 2674, 65.6% female, Mean age = 24.6, SD = 8.6, range = 18-65 years). Network community analysis demonstrated that compulsivity was constituted of three interrelated dimensions, namely: perfectionism, cognitive rigidity and reward drive. Further, 'Completion leads to soothing' and 'Difficulty moving from task to task' were identified as core (central nodes) to compulsivity. The dimensional structure and central nodes of compulsivity networks were consistent across the two samples. These findings facilitate the conceptualisation and measurement of compulsivity and may contribute to the early detection and treatment of compulsivity-related disorders.

Pathological Networking of Gray Matter Dendritic Density With Classic Brain Morphometries in OCD

Importance

The pathogenesis of obsessive-compulsive disorder (OCD) may involve altered dendritic morphology, but in vivo imaging of neurite morphology in OCD remains limited. Such changes must be interpreted functionally within the context of the multimodal neuroimaging approach to OCD.

Objective

To examine whether dendritic morphology is altered in patients with OCD compared with healthy controls (HCs) and whether such alterations are associated with other brain structural metrics in pathological networks.

Design, Setting, and Participants

This case-control study used cross-sectional data, including multimodal brain images and clinical symptom assessments, from 108 patients with OCD and 108 HCs from 2014 to 2017. Patients with OCD were recruited from Shanghai Mental Health Center, Shanghai, China, and HCs were recruited via advertisements. The OCD group comprised unmedicated adults with a Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV) diagnosis of OCD, while the HCs were adults without any DSM-IV diagnosis, matched for age, sex, and education level. Data were analyzed from September 2019 to April 2023.

Exposure

DSM-IV diagnosis of OCD.

Main Outcomes and Measures

Multimodal brain imaging was used to compare neurite microstructure and classic morphometries between patients with OCD and HCs. The whole brain was searched to identify regions exhibiting altered morphology in patients with OCD and explore the interplay between the brain metrics representing these alterations. Brain-symptom correlations were analyzed, and the performance of different brain metric configurations were evaluated in distinguishing patients with OCD from HCs.

Results

Among 108 HCs (median [IQR] age, 26 [23-31] years; 50 [46%] female) and 108 patients with OCD (median [IQR] age, 26 [24-31] years; 46 [43%] female), patients with OCD exhibited deficient neurite density in the right lateral occipitoparietal regions (peak t = 3.821; P ≤ .04). Classic morphometries also revealed widely-distributed alterations in the brain (peak t = 4.852; maximum P = .04), including the prefrontal, medial parietal, cingulate, and fusiform cortices. These brain metrics were interconnected into a pathological brain network associated with OCD symptoms (global strength: HCs, 0.253; patients with OCD, 0.941; P = .046; structural difference, 0.572; P < .001). Additionally, the neurite density index exhibited high discriminatory power in distinguishing patients with OCD from HCs (accuracy, ≤76.85%), and the entire pathological brain network also exhibited excellent discriminative classification properties (accuracy, ≤82.87%).

Conclusions and Relevance

The findings of this case-control study underscore the utility of in vivo imaging of gray matter dendritic density in future OCD research and the development of neuroimaging-based biomarkers. They also endorse the concept of connectopathy, providing a potential framework for interpreting the associations among various OCD symptom-related morphological anomalies.

Obsessive-Compulsive Symptoms in Children Are Related to Sensory Sensitivity and to Seeking Proxies for Internal States

Symptoms of obsessive-compulsive disorder are related to atypical sensory processing, particularly sensory over-responsivity, in both children and adults. In adults, obsessive-compulsive symptoms are also associated with the attenuation of access to the internal state and compensatory reliance on proxies for these states, including fixed rules and rituals. We aimed to examine the associations between sensory over-responsivity, the tendency to seek proxies for internal states, and obsessive-compulsive symptoms in children. Parents of 404 children between 5 and 10 years of age completed online measures of obsessive-compulsive symptoms, seeking proxies for internal states, sensory over-responsivity, and anxiety. Linear regression, dominance analysis, and network analysis were used to explore the unique associations between these variables. The tendency to seek proxies for internal states was more strongly associated with obsessive-compulsive symptoms than with anxiety symptoms and uniquely associated with all major obsessive-compulsive symptom dimensions except obsessing. Both the tendency to seek proxies for internal states and sensory over-responsivity were significantly associated with obsessive-compulsive symptoms, but the association was significantly stronger for the tendency to seek proxies for internal states. While limited by the sole reliance on the parent-report, the present study shows that the tendency to seek proxies for internal states could help clarify the developmental processes involved in the onset of obsessive-compulsive symptoms during childhood and that sensory sensitivity may be important to consider in this process.

Everyday executive functioning in pediatric obsessive-compulsive disorder: diagnostic specificity, clinical correlations, and outcome

BACKGROUND

Obsessive-compulsive disorder (OCD) typically onsets during childhood or adolescence and difficulties with executive functioning (EF) may be involved in its onset and maintenance. Yet, few studies have examined everyday EF difficulties in youth with OCD and no study has compared EF in youth with OCD to EF in youth with anxiety disorders, leaving the diagnostic specificity of EF unclear.

METHODS

In this study, parents of treatment-seeking children and adolescents with OCD (n = 96, Mage = 13.3, SD = 2.7, 59% girls) or anxiety disorders (n = 67, Mage = 14.0, SD = 2.6, 78% girls) reported on their children's everyday EF using the Behavior Rating Inventory of Executive Function (BRIEF) measure.

RESULTS

Compared to community youth, the two clinical groups showed moderately elevated EF deficits but did not differ significantly from each other. EF deficits were not associated with the major symptom dimensions of OCD, age of OCD symptom onset, duration of OCD symptoms, and OCD severity, and did not predict treatment outcome in OCD.

CONCLUSIONS

Compared to peers, youth with OCD show moderate difficulties with EF, but very similar difficulties are seen in youth with anxiety disorders, and it is unclear whether these difficulties are of clinical relevance. Among youth with OCD, EF difficulties were not differentially associated with the major symptom dimensions of OCD, which is inconsistent with findings from adults. Difficulties with EF did not predict treatment outcome, indicating that integrating EF modules into OCD treatment may be of limited value, although EF may be important for treatment planning in individual cases.

Comparative neurogenetics of dog behavior complements efforts towards human neuropsychiatric genetics

Domestic dogs display a wide array of heritable behaviors that have intermediate genetic complexity thanks to a long history of human-influenced selection. Comparative genetics in dogs could address the scarcity of non-human neurogenetic systems relevant to human neuropsychiatric disorders, which are characterized by mental, emotional, and behavioral symptoms and involve vastly complex genetic and non-genetic risk factors. Our review describes the diverse behavioral "phenome" of domestic dogs, past and ongoing sources of behavioral selection, and the state of canine behavioral genetics. We highlight two naturally disordered behavioral domains that illustrate how dogs may prove useful as a comparative, forward neurogenetic system: canine age-related cognitive dysfunction, which can be examined more rapidly given the attenuated lifespan of dogs, and compulsive disorders, which may have genetic roots in purpose-bred behaviors. Growing community science initiatives aimed at the companion dog population will be well suited to investigating such complex behavioral phenotypes and offer a comparative resource that parallels human genomic initiatives in scale and dimensionality.

Symptom Dimension Breakpoints for the Obsessive-Compulsive Inventory-Child Version (OCI-CV)

Pediatric obsessive-compulsive disorder (OCD) clusters around three major symptom dimensions: contamination/cleaning, symmetry/ordering, and disturbing thoughts/checking. The Obsessive-Compulsive Inventory-Child Version (OCI-CV) is a self-report questionnaire that provides scores along six theory-based OCD dimensions, but no study has evaluated how well OCI-CV identifies clinically significant symptoms within each of the three major symptom dimensions of OCD. We examined this question using data from 197 Swedish and Spanish youth with OCD. All youth completed the OCI-CV and clinically significant symptom severity within each major OCD dimension was established with a validated interview-based measure. Results showed that a score ≥ 3 on the OCI-CV washing scale excellently captured those with clinically significant contamination/cleaning symptoms (AUC = 0.85 [0.80-0.90], 79% accuracy). A score ≥ 4 on the obsessing scale adequately captured those with disturbing thoughts/checking symptoms (AUC = 0.71 [0.64-0.78], 67% accuracy) and a score ≥ 3 on the ordering scale adequately captured those with symmetry/ordering symptoms (AUC = 0.72 [0.65-0.79], 70% accuracy). Similar accuracy of the breakpoints was found in the Swedish and Spanish samples. OCI-CV works well to identify youth with pediatric OCD that have clinically significant contamination/cleaning symptoms. The measure can also with adequate precision identify those with clinically significant disturbing thoughts/checking and symmetry/ordering symptoms. The breakpoints provided in this study can be used to examine differences in clinical presentation and treatment outcome for youth with different types of OCD.

Relationship between Cognitive Strategies of Emotion Regulation and Dimensions of Obsessive-Compulsive Symptomatology in Adolescents

Cognitive emotion regulation refers to the management of one's emotions through cognitive strategies. Studies have found that individuals with obsessive-compulsive symptoms utilize emotion regulation strategies differently compared to those without these symptoms. This study aims to investigate the relationship between cognitive strategies for emotion regulation and specific dimensions of obsessive-compulsive symptoms in adolescents. A cross-sectional descriptive study was conducted with 307 adolescents between 12 and 18 years old. Associations between sociodemographic variables, obsessive-compulsive symptoms, and emotion regulation strategies were examined using regression and network analyses. Regression results indicated that emotion regulation strategies and gender accounted for 28.2% of the variation in overall obsessive-compulsive symptoms (p < 0.001) and that emotion regulation explained most variance in the symptom dimension of obsessing. Network analysis showed that self-blame and catastrophizing were uniquely linked to overall obsessive-compulsive symptoms, while several strategies were uniquely linked to specific symptom dimensions. The adaptive strategy that demonstrated the strongest association with obsessive-compulsive symptoms was refocus on planning, while maladaptive strategies included catastrophizing, self-blame, and rumination. In conclusion, the results support the relationship between cognitive strategies for emotion regulation and dimensions of obsessive-compulsive symptoms in adolescents, though these relations appear complex and require further investigation. Addressing emotion regulation in the prevention of obsessive-compulsive symptoms may be warranted, but prospective studies are needed.

Treatment of disgust in specific emotional disorders

Although conditioning approaches have highlighted potential characteristics of disgust in anxiety disorders, obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD), these findings have yet to be translated into evidence-based treatments. Examination of the literature suggests various indicators of disgust that predict treatment outcome in these disorders. However, mechanisms remain unclear because studies examining disgust during the course of treatment are limited. Increasingly, the field has moved toward experimental investigation of strategies that reduce disgust. While cognitive reappraisal and imagery techniques appear promising, such techniques have yet to be examined as anxiety disorder treatments in large-scale randomized clinical trials. The literature also points to novel approaches to treating disgust, ranging from an inhibitory-informed approach to exposure therapy to transcranial direct current stimulation. However, the development of novel treatment approaches will require more rigorous experimental psychopathology approaches that can further elucidate processes that contribute to the etiology and/or maintenance of disorders of disgust.

Sensory Processing Difficulties in Children and Adolescents with Obsessive-Compulsive and Anxiety Disorders

Altered sensory processing has been linked to symptoms of obsessive-compulsive disorder (OCD) and anxiety disorders (ADs) in youth, but few studies have examined sensory processing in clinical samples and no study has analyzed self-report data from youth meeting diagnostic criteria for OCD or ADs. This study included 86 youth with OCD, 82 youth with ADs, and 46 youth without psychiatric disorders. Participants completed the adolescent version of the Sensory Profile and scales measuring three symptom dimensions of OCD, four symptom dimensions of anxiety, and symptoms of major depression. Results showed that different forms of sensory processing difficulties (sensitivity, avoidance, low registration) were adequately captured by one broad sensory processing factor. Youth with OCD and ADs reported statistically significantly more sensory difficulties than youth without psychiatric disorders, but the two clinical groups did not differ from each other. Altered sensory processing in the clinical groups was not explained by the presence of neurodevelopmental disorders. Sensory difficulties were moderately to strongly related to all self-reported symptom dimensions, and uniquely related to the OCD dimension of symmetry/ordering and the anxiety dimensions of panic and social anxiety. Most youth in the clinical groups were classified as having difficulties with sensory processing. The present study shows that sensory processing difficulties are common in youth with OCD and ADs, not explained by co-occurring neurodevelopmental disorders, and linked to a host of internalizing symptoms. More research is needed to identify whether sensory processing difficulties precede, follow, or mutually reinforce the development of OCD and ADs in youth.

Measuring symptoms of obsessive-compulsive and related disorders using a single dimensional self-report scale

BACKGROUND

Obsessions and compulsions are heterogenous but can be classified into obsessive-compulsive disorder (OCD), body dysmorphic disorder (BDD), hoarding disorder (HD), hair-pulling disorder (HPD), and skin-picking disorder (SPD). OCD is in itself heterogenous, with symptoms clustering around four major symptom dimensions: contamination/cleaning, symmetry/ordering, taboo obsessions, and harm/checking. No single self-report scale captures the full heterogeneity of OCD and related disorders, limiting assessment in clinical practice and research on nosological relations among the disorders.

METHODS

To provide a single self-report scale of OCD and related disorders that respects the heterogeneity of OCD, we expanded the DSM-5-based Obsessive-Compulsive and Related Disorders-Dimensional Scales (OCRD-D) so that is also includes the four major symptom dimensions of OCD. A psychometric evaluation and an exploration of the overarching relations among the dimensions were conducted using an online survey which was completed by 1,454 Spanish adolescents and adults (age span = 15-74 years). Approximately 8 months after the initial survey, 416 participants completed the scale again.

RESULTS

The expanded scale showed excellent internal psychometric properties, adequate test-retest correlations, known groups validity, and correlations in the expected directions with well-being, depression/anxiety symptoms, and satisfaction with life. The higher-order structure of the measure indicated that harm/checking and taboo obsessions formed a common disturbing thoughts factor and that HPD and SPD formed a common body-focused repetitive behaviors factor.

CONCLUSION

The expanded OCRD-D (OCRD-D-E) shows promise as a unified way to assess symptoms across the major symptom dimensions of OCD and related disorders. The measure may be useful in clinical practice (e.g., screening) and research, but more research on construct validity, incremental validity, and clinical utility is needed.

Neurobiological outcomes of cognitive behavioral therapy for obsessive-compulsive disorder: A systematic review

Introduction

Obsessive-compulsive disorder (OCD) is characterized by recurrent distressing thoughts and repetitive behaviors, or mental rituals performed to reduce anxiety. Recent neurobiological techniques have been particularly convincing in suggesting that cortico-striatal-thalamic-cortico (CSTC) circuits, including orbitofrontal cortex (OFC) and striatum regions (caudate nucleus and putamen), are responsible for mediation of OCD symptoms. However, it is still unclear how these regions are affected by OCD treatments in adult patients. To address this yet open question, we conducted a systematic review of all studies examining neurobiological changes before and after first-line psychological OCD treatment, i.e., cognitive-behavioral therapy (CBT).

Methods

Studies were included if they were conducted in adults with OCD and they assessed the neurobiological effects of CBT before and after treatment. Two databases were searched: PsycINFO and PubMed for the time frame up to May 2022.

Results

We obtained 26 pre-post CBT treatment studies performed using different neurobiological techniques, namely functional magnetic resonance imaging (fMRI), Positron emission tomography (PET), regional cerebral blood flow (rCBF), 5-HT concentration, magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), Electroencephalography (EEG). Neurobiological data show the following after CBT intervention: (i) reduced activations in OFC across fMRI, EEG, and rCBF; (ii) decreased activity in striatum regions across fMRI, rCBF, PET, and MRI; (iii) increased activations in cerebellum (CER) across fMRI and MRI; (iv) enhanced neurochemical concentrations in MRS studies in OFC, anterior cingulate cortex (ACC) and striatum regions. Most of these neurobiological changes are also accompanied by an improvement in symptom severity as assessed by a reduction in the Y-BOCS scores.

Conclusion

Cognitive-behavioral therapy seems to be able to restructure, modify, and transform the neurobiological component of OCD, in addition to the clinical symptoms. Nevertheless, further studies are necessary to frame the OCD spectrum in a dimensional way.

Co-occurring depression and obsessive-compulsive disorder: A dimensional network approach

BACKGROUND

Depressive and obsessive-compulsive (OCD) symptoms often co-occur and a number of possible explanations for this co-occurrence have been explored, including shared biological and psychosocial risk factors. Network approaches have offered a novel hypothesis for the link between depression and OCD: functional inter-relationships across the symptoms of these conditions. The few network studies in this area have relied largely on item, rather than process-level constructs, and have not examined relationships dimensionally.

METHODS

Network analytic methods were applied to data from 463 treatment-seeking adults with OCD. Patients completed self-report measures of OCD and depression. Factor analysis was used to derive processes (i.e., nodes) to include in the network. Networks were computed, and centrality, bridge, and stability statistics examined.

RESULTS

Networks showed positive relations among specific OCD and depressive symptoms. Obsessions (particularly repugnant thoughts), negative affectivity, and cognitive-somatic changes (e.g., difficulty concentrating) were central to the network. Unique relations were observed between symmetry OCD symptoms and cognitive-somatic changes. No direct link between harm-related OCD symptoms and depression was observed.

CONCLUSIONS

Our results bring together prior findings, suggesting that both negative affective and psychomotor changes are important to consider in examining the relationship between OCD and depression. Increased consideration of heterogeneity in the content of OCD symptoms is key to improving clinical conceptualizations, particularly when considering the co-occurrence of OCD with other disorders.

Initial evaluation of a therapist-supported online cognitive therapy self-help for patients with taboo obsessions

OBJECTIVES

The current study evaluated the feasibility of an internet-delivered cognitive therapy (I-CT) in a self-help format with minimal therapist support for patients with obsessive-compulsive disorder (OCD) with primary taboo obsessions. Specifically, the aims were to investigate (1) whether participants were able to grasp and apply the internet-delivered cognitive framework to their own situation; (2) whether they had clinically meaningful reductions of OCD symptom severity; and (3) whether reduced negative appraisals (hypothesized mechanism of change in CT) preceded reductions in OCD symptom severity.

METHOD

Nineteen OCD patients with primary taboo obsessions, recruited from an OCD clinic or self-referrals, received the I-CT intervention for 10 weeks. I-CT did not contain any systematic exposure or response prevention.

RESULTS

Adherence and engagement with the intervention was high. Most participants (n = 13, 68%) understood and successfully applied the cognitive model to their own situation. Within-group analyses showed large reductions in OCD symptom severity at post-treatment (bootstrapped within group d = 1.67 [95% CI; 0.67 to 2.66]) measured with the Yale-Brown Obsessive-Compulsive Scale. The gains were maintained at the 6-month follow-up. Post-hoc analyses revealed that the large reductions in OCD symptom severity were driven by the participants who understood the cognitive model. Reductions in negative appraisals predicted subsequent reductions in OCD symptom severity during treatment.

CONCLUSION

It is possible to adapt a purely cognitive intervention to a digital guided self-help format and to achieve both cognitive change and meaningful symptom reduction. The results require confirmation in a randomized clinical trial.

Elevated Anxious and Depressed Mood Relates to Future Executive Dysfunction in Older Adults: A Longitudinal Network Analysis of Psychopathology and Cognitive Functioning

Vulnerability models posit that executive-functioning (EF) problems centrally affect future common (vs. rare) psychopathology symptoms. Conversely, scar theory postulates that depression/anxiety (vs. other psychopathology) symptoms centrally influence reduced EF. However, most studies so far have been cross-sectional. We used cross-lagged panel network analysis to determine temporal and component-to-component relations on this topic. Community older adults participated across four time points. Cognitive tests and the caregiver-rated Neuropsychiatric Inventory assessed nine psychopathology and eight cognitive-functioning nodes. Nodes with the highest bridge expected influence cross-sectionally were agitation and episodic memory. Episodic memory had the strongest inverse relation with age. Agitation had the strongest negative association with global cognition. EF nodes tended to be centrally affected by prior depressed and anxious moods rather than influential on any future nodes. Heightened anxious and depressed mood (vs. other nodes) centrally predicted future decreased EF-related (vs. non-EF-related) nodes in older adults, supporting scar (vs. vulnerability) theory.

Taboo obsessions and their association with suicidality in obsessive-compulsive disorder

Individuals with obsessive-compulsive disorder (OCD) more often think about, attempt, and die by suicide than individuals from the general population. Sexual and religious obsessions (i.e., taboo obsessions) have been linked to increased risk of suicidality, but it is unclear if they explain additional risk over and above other risk factors. We refined the recently proposed multidimensional hierarchical model of OCD and explored how each symptom dimension in the model was associated with suicidality in a random half (n = 500) of a well-characterized cohort of patients with OCD. Symptom dimensions and other risk factors significantly associated with suicidality were included in a confirmatory multivariable model conducted with the other half of the sample (n = 501). The predictive confirmatory model accounted for 19% of the variance in suicidality. Taboo obsessions, the general OCD factor (i.e., having many different OCD symptoms at the same time), lifetime major depression, and lifetime substance use disorders significantly predicted suicidality in this model. Lifetime major depression explained most unique variance in suicidality (5.6%) followed by taboo obsessions and the general OCD factor (1.9% each). Taboo obsessions explain a small but significant proportion of variance in suicidality and should be considered an independent risk factor for suicidality in patients with OCD.

A systematic review on the links between emotion regulation difficulties and obsessive-compulsive disorder

BACKGROUND

Growing evidence suggests a link between emotion regulation (ER) deficits and obsessive-compulsive symptoms (OCS).

AIMS

A systematic review was conducted to integrate empirical research on the nature of ER difficulties associated with obsessive-compulsive disorder (OCD), validated measures of ER for OCD and evidence base for psychological interventions targeting ER difficulties in OCD.

METHODS

Database searches were conducted on CINAHL, Cochrane Library, EMBASE, MEDLINE, PUBMED, PsycINFO and Scopus with keywords related to ER and OCD. 2609 articles were found, six were identified from other sources and 21 studies were included in this review. The review was registered on PROSPERO (CDR42020184076).

RESULTS

The non-acceptance of emotions was the most consistently related to OCS - albeit not uniformly with all OCS dimensions. There was also some evidence suggesting that difficulties in impulse-control, accessing effective ER strategies and engaging in goal-directed behaviours to be related to OCS. No OCD-specific ER measure was identified. Interventions with ER components appeared to be promising for the treatment of OCD.

FUTURE DIRECTIONS

Recommendations on how to build on the existing literature and improve the quality of evidence were provided.

A multi-group confirmatory factor analysis of the revised children's anxiety and depression scale (RCADS) in Spain, Chile and Sweden

BACKGROUND

There is a need for a measure that can be used across countries and cultures to advance cross-cultural research about internalizing mental health symptoms in children and adolescents. The Revised Children's Anxiety and Depression Scale (RCADS) is a potential candidate, but no study has examined whether its scales are measured similarly in youth populations from different countries.

METHODS

In this study, we use confirmatory factor analysis (CFA) and multi-group CFA to examine the cross-cultural properties of a short and free to use 30-item version of RCADS that assesses social, generalized, panic, and separation anxiety alongside depression and obsessive-compulsive symptoms. We tested the factor structure of RCADS in children and adolescents from Chile, Spain, and Sweden, recruited using different research designs (i.e., school-based studies and an anonymous web survey), and whether the factor structure showed measurement invariance across the three countries.

RESULTS

The proposed factor structure of RCADS showed good model/data fit in all three countries and was superior to a unidimensional model in which correlations among scale items were explained by a single broad internalizing factor. Each RCADS subscale showed adequate to excellent internal consistency in all three countries and multi-group CFA supported scalar invariance across the three countries.

LIMITATIONS

No clinical sample was included.

CONCLUSIONS

This study provides an important first step in supporting the use of RCADS in cross-cultural research on depression, anxiety and obsessive-compulsive symptoms in children and adolescents, but more work on validity aspects of the scale across cultures is needed.

Functional Connectivity within the Frontal–Striatal Network Differentiates Checkers from Washers of Obsessive-Compulsive Disorder

Background: Obsessive-compulsive disorder (OCD) is a psychiatric disorder with high clinical heterogeneity manifested by the presence of obsessions and/or compulsions. The classification of the symptom dimensional subtypes is helpful for further exploration of the pathophysiological mechanisms underlying the clinical heterogeneity of OCD. Washing and checking symptoms are the two major symptom subtypes in OCD, but the neural mechanisms of the different types of symptoms are not yet clearly understood. The purpose of this study was to compare regional and network functional alterations between washing and checking OCD based on resting-state functional magnetic resonance imaging (rs-fMRI). Methods: In total, 90 subjects were included, including 15 patients in the washing group, 30 patients in the checking group, and 45 healthy controls (HCs). Regional homogeneity (ReHo) was used to compare the differences in regional spontaneous neural activity among the three groups, and local indicators were analyzed by receiver operating characteristic (ROC) curves as imaging markers for the prediction of the clinical subtypes of OCD. Furthermore, differently activated local brain areas, as regions of interest (ROIs), were used to explore differences in altered brain functioning between washing and checking OCD symptoms based on a functional connectivity (FC) analysis. Results: Extensive abnormalities in spontaneous brain activity involving frontal, temporal, and occipital regions were observed in the patients compared to the HCs. The differences in local brain functioning between checking and washing OCD were mainly concentrated in the bilateral middle frontal gyrus, right supramarginal gyrus, right angular gyrus, and right inferior occipital gyrus. The ROC curve analysis revealed that the hyperactivation right middle frontal gyrus had a better discriminatory value for checking and washing OCD. Furthermore, the seed-based FC analysis revealed higher FC between the left medial superior frontal gyrus and right caudate nucleus compared to that in the healthy controls. Conclusions: These findings suggest that extensive local differences exist in intrinsic spontaneous activity among the checking group, washing group, and HCs. The neural basis of checking OCD may be related to dysfunction in the frontal–striatal network, which distinguishes OCD from washing OCD.

Sensory over-responsivity and symptoms across the obsessive-compulsive spectrum: a web-based study (Preprint)

BACKGROUND

Sensory overresponsivity (SOR) has emerged as a potential endophenotype in obsessive-compulsive disorder (OCD), but few studies have examined SOR in relation to the major symptom dimensions of OCD and to symptoms across the full obsessive-compulsive (OC) symptom spectrum.

OBJECTIVE

This study had 2 main objectives. First, we examined the psychometric properties of the SOR Scales in a community-based sample of Spanish adolescents and adults. Second, we identified how SOR difficulties are related to symptoms across the full OC spectrum (eg, OC, body dysmorphic, hoarding, skin-picking, and hair-pulling symptoms), including the heterogeneity of OC symptoms.

METHODS

We translated the SOR Scales into Spanish-a measure that assesses SOR across the 5 sensory modalities-and created a web-based version of the measure. A sample of 1454 adolescents and adults (mean age 23.84, SD 8.46 years) participated in the study, and 388 (26.69%) participants completed the survey twice (approximately 8 months apart). The survey also contained a web-based measure that assesses symptoms across the full OC spectrum: harm and checking, taboo obsessions, contamination or cleaning, symmetry and ordering, body dysmorphic, hoarding, hair-pulling, and skin-picking symptoms.

RESULTS

The psychometric properties of the SOR Scales were excellent, and the test-retest reliability was adequate. All types of SOR were related to all major symptom dimensions of OCD and to all OC spectrum symptoms.

CONCLUSIONS

SOR across the sensory modalities can be validly assessed using a web-based measure. SOR emerged as a pure transdiagnostic phenomenon in relation to symptoms across the OC spectrum, with no specific sensory modality being more strongly related to OC symptoms. SOR can shed much needed light on basic mechanisms that are important for the onset and maintenance of OC spectrum symptoms, and this study shows that large-scale web-based studies can aid in this endeavor. Future studies should examine whether SOR precedes or emerges alongside OC symptoms.

Cognitive Beliefs Across the Symptom Dimensions of Pediatric Obsessive-Compulsive Disorder: Type of Symptom Matters

The cognitive model of obsessive-compulsive disorder (OCD) posits that dysfunctional cognitive beliefs are crucial to the onset and maintenance of OCD; however, the relationship between these cognitive beliefs and the heterogeneity of OCD symptoms in children and adolescents remains unknown. We examined how the major belief domains of the cognitive model (inflated responsibility/threat estimation, perfectionism/intolerance of uncertainty, importance/control of thoughts) and dysfunctional metacognitions were related to OCD symptoms across the following dimensions: doubting/checking, obsessing, hoarding, washing, ordering, and neutralization. Self-report ratings from 137 treatment-seeking youth with OCD were analyzed. When cognitive beliefs and symptom dimensions were analyzed in tandem, inflated responsibility/threat estimation and dysfunctional metacognitions were uniquely related to doubting/checking, obsessing, and hoarding and perfectionism/intolerance of uncertainty to ordering. Cognitive beliefs explained a large proportion of variation in doubting/checking (61%) and obsessing (46%), but much less so in ordering (15%), hoarding (14%), neutralization (8%), and washing (3%). Similar relations between cognitive beliefs and symptom dimensions were present in children and adolescents. Cognitive beliefs appear to be relevant for pediatric OCD related to harm, responsibility, and checking, but they do not map clearly onto contamination and symmetry-related symptoms. Implications for OCD etiology and treatment are discussed.

The Genetic Architecture of Obsessive-Compulsive Disorder: Contribution of Liability to OCD From Alleles Across the Frequency Spectrum

OBJECTIVE

Obsessive-compulsive disorder (OCD) is known to be substantially heritable; however, the contribution of genetic variation across the allele frequency spectrum to this heritability remains uncertain. The authors used two new homogeneous cohorts to estimate the heritability of OCD from inherited genetic variation and contrasted the results with those of previous studies.

METHODS

The sample consisted of 2,090 Swedish-born individuals diagnosed with OCD and 4,567 control subjects, all genotyped for common genetic variants, specifically >400,000 single-nucleotide polymorphisms (SNPs) with minor allele frequency (MAF) ≥0.01. Using genotypes of these SNPs to estimate distant familial relationships among individuals, the authors estimated the heritability of OCD, both overall and partitioned according to MAF bins.

RESULTS

Narrow-sense heritability of OCD was estimated at 29% (SE=4%). The estimate was robust, varying only modestly under different models. Contrary to an earlier study, however, SNPs with MAF between 0.01 and 0.05 accounted for 10% of heritability, and estimated heritability per MAF bin roughly followed expectations based on a simple model for SNP-based heritability.

CONCLUSIONS

These results indicate that common inherited risk variation (MAF ≥0.01) accounts for most of the heritable variation in OCD. SNPs with low MAF contribute meaningfully to the heritability of OCD, and the results are consistent with expectation under the "infinitesimal model" (also referred to as the "polygenic model"), where risk is influenced by a large number of loci across the genome and across MAF bins.

Comparison of Hypomanic Symptoms Between Bipolar I and Bipolar II Disorders: A Network Perspective

BACKGROUND

Hypomanic symptoms between bipolar-I disorder (BD-I) and bipolar-II disorder (BD-II) are often indistinguishable in clinical practice. This study compared the network structure of hypomanic symptoms between patients with BD-I and BD-II.

METHODS

The 32-item Hypomania Checklist (HCL-32) was used to assess hypomanic symptoms. Network model was generated in BD-I and BD-II patients. Centrality index of strength was used to quantify the importance of each symptom in the network. The Network Comparison Test (NCT) was used to assess the differences in hypomanic symptoms between BD-I and BD-II patients.

RESULTS

Altogether, 423 patients with BD (BD-I: 191 and BD-II: 232) were included. The most central symptom was HCL17 "I am more flirtatious and/or am more sexually active" (strength _BD-I = 5.21) and HCL12 "I have more ideas, I am more creative" (strength _BD-II = 6.84) in BD-I and BD-II samples, respectively. The results of NCT showed that four nodes (HCL12 "I have more ideas, I am more creative," HCL17 "I am more flirtatious and/or am more sexually active," HCL23 "My thoughts jump from topic to topic," and HCL31 "I drink more alcohol") were significantly different between the BD-I and BD-II samples. Two edges (HCL3 "I am more self-confident"-HCL17 "I am more flirtatious and/or am more sexually active," and HCL10 "I am physically more active (sport, etc.)"-HCL24 "I do things more quickly and/or more easily") were significantly stronger in BD-I compared to BD-II patients.

CONCLUSION

The network structure of hypomanic symptoms is different between BD-I and BD-II patients. Interventions targeting the respective central symptoms and edges should be developed for BD-I and BD-II separately.

Factor structure of the Dimensional Yale-Brown Obsessive-Compulsive Scale in a large sample of adults with obsessive-compulsive disorder

Objectives:

Although the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) is a widely used instrument for assessing different obsessive-compulsive symptom dimensions, its factor structure has never been studied in a Brazilian population. Thus, we aimed to assess the goodness-of-fit indexes and factor loadings of two higher-order models of the DY-BOCS using confirmatory factor analysis (CFA) in a large obsessive-compulsive disorder (OCD) sample.

Methods:

We tested two CFA models in a sample of 955 adults with OCD who had been assessed with the DY-BOCS in a cross-sectional multi-site study. The first model encompassed the symptom checklist (present or absent), whereas the second focused on items related to severity scores.

Results:

Both models presented adequate goodness-of-fit indexes. The comparative fit index, Tucker-Lewis index, and omega were > 0.9, while the root mean square error of approximation was ≤ 0.06 for both models. Factor loadings for each item of each dimension are presented and discussed.

Conclusion:

Higher-order factor models showed adequate goodness-of-fit indexes, indicating that they appropriately measured OCD dimensions in this Brazilian population.

Elevated C-reactive protein levels across diagnoses: The first comparison among inpatients with major depressive disorder, bipolar disorder, or obsessive-compulsive disorder

OBJECTIVE

We addressed elevated C-reactive protein level (eCRP) specificity comparing, for the first time, eCRP (i.e., serum CRP > 3 and ≤10 mg/L) in patients with major depressive disorder (MDD), bipolar disorder (BD), or obsessive-compulsive disorder (OCD). We also assessed to what extent multiple variables that can potentially increase inflammation may have influenced eCRP in our sample.

METHODS

We performed a retrospective, observational, cross-sectional study using information documented in the electronic medical records (EMRs) of patients hospitalized for a 4-week psychiatric rehabilitation program. We collected all information according to the standardized procedures of the hospital's clinical practice and applied a logistic regression model (α = 0.05).

RESULTS

We included 388 inpatients, that is, 156 (40.2%) with MDD, 135 (34.8%) with BD, and 97 (25.0%) with OCD, and found considerable eCRP rates among them (36.5%, 47.4%, and 29.9% in MDD, BD, and OCD, respectively) but without significant differences across groups. In the whole sample, eCRP variations were only partially attributable (approximately for one-third) to potential confounders. All groups presented considerable rates of cardiovascular risk factors, and we classified most patients as having medium or high CRP-based cardiovascular risk.

CONCLUSION

This first study comparing eCRP in MDD, BD, and OCD suggests that eCRP may be a transdiagnostic feature of different psychiatric disorders, and other mechanisms beyond the effects of multiple confounders may explain the presence of eCRP in a substantial portion of psychiatric patients. Therefore, we encourage the routine measurement of CRP in psychiatric clinical practice.

Neural correlates of fear conditioning and fear extinction and its association with cognitive-behavioral therapy outcome in adults with obsessive-compulsive disorder

Recent neurobiological models of obsessive-compulsive disorder (OCD) have highlighted the potential role of abnormalities in fear learning processes. We compared brain activation -as assessed with whole-brain functional magnetic resonance imaging- during fear conditioning, fear extinction learning, and fear extinction recall in patients with OCD (n = 18) and healthy controls (n = 18). We also investigated whether brain activation during any of these processes was associated with exposure-based cognitive-behavioral therapy (CBT) outcome in patients. Patients with OCD showed significantly lower brain activation in the right insulo-opercular region and the dorsal anterior cingulate cortex during fear conditioning in comparison to healthy controls. Moreover, brain activation in the right insula predicted CBT outcome, with lower activation predicting a better outcome. Brain activation during extinction learning or recall did not differ between patients and controls or predicted CBT outcome in patients. Our results suggest that neural activations during fear conditioning in patients with OCD are abnormal and predict CBT outcome.

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.