White matter diffusion estimates in obsessive-compulsive disorder across 1653 individuals: machine learning findings from the ENIGMA OCD Working Group.

White matter pathways, typically studied with diffusion tensor imaging (DTI), have been implicated in the neurobiology of obsessive-compulsive disorder (OCD). However, due to limited sample sizes and the predominance of single-site studies, the generalizability of OCD classification based on diffusion white matter estimates remains unclear. Here, we tested classification accuracy using the largest OCD DTI dataset to date, involving 1336 adult participants (690 OCD patients and 646 healthy controls) and 317 pediatric participants (175 OCD patients and 142 healthy controls) from 18 international sites within the ENIGMA OCD Working Group. We used an automatic machine learning pipeline (with feature engineering and selection, and model optimization) and examined the cross-site generalizability of the OCD classification models using leave-one-site-out cross-validation. Our models showed low-to-moderate accuracy in classifying (1) "OCD vs. healthy controls" (Adults, receiver operator characteristic-area under the curve = 57.19 ± 3.47 in the replication set; Children, 59.8 ± 7.39), (2) "unmedicated OCD vs. healthy controls" (Adults, 62.67 ± 3.84; Children, 48.51 ± 10.14), and (3) "medicated OCD vs. unmedicated OCD" (Adults, 76.72 ± 3.97; Children, 72.45 ± 8.87). There was significant site variability in model performance (cross-validated ROC AUC ranges 51.6-79.1 in adults; 35.9-63.2 in children). Machine learning interpretation showed that diffusivity measures of the corpus callosum, internal capsule, and posterior thalamic radiation contributed to the classification of OCD from HC. The classification performance appeared greater than the model trained on grey matter morphometry in the prior ENIGMA OCD study (our study includes subsamples from the morphometry study). Taken together, this study points to the meaningful multivariate patterns of white matter features relevant to the neurobiology of OCD, but with low-to-moderate classification accuracy. The OCD classification performance may be constrained by site variability and medication effects on the white matter integrity, indicating room for improvement for future research.

First trans-diagnostic experiences with a novel micro-choice based concentrated group rehabilitation for patients with low back pain, long COVID, and type 2 diabetes: a pilot study.

BACKGROUND: The health care is likely to break down unless we are able to increase the level of functioning for the growing number of patients with complex, chronic illnesses. Hence, novel high-capacity and cost-effective treatments with trans-diagnostic effects are warranted. In accordance with the protocol paper, we aimed to examine the acceptability, satisfaction, and effectiveness of an interdisciplinary micro-choice based concentrated group rehabilitation for patients with chronic low back pain, long COVID, and type 2 diabetes. METHODS: Patients with low back pain > 4 months sick-leave, long COVID, or type 2 diabetes were included in this clinical trial with pre-post design and 3-month follow-up. The treatment consisted of three phases: (1) preparing for change, (2) the concentrated intervention for 3-4 days, and (3) integrating change into everyday life. Patients were taught and practiced how to monitor and target seemingly insignificant everyday micro-choices, in order to break the patterns where symptoms or habits contributed to decreased levels of functioning or increased health problems. The treatment was delivered to groups (max 10 people) with similar illnesses. Client Satisfaction Questionnaire (CSQ-8)) (1 week), Work and Social Adjustment Scale (WSAS), Brief Illness Perception Questionnaire (BIPQ), and self-rated health status (EQ-5D-5L) were registered at baseline and 3-month follow-up. RESULTS: Of the 241 included participants (57% women, mean age 48 years, range 19-84), 99% completed the concentrated treatment. Treatment satisfaction was high with a 28.9 (3.2) mean CSQ-8-score. WSAS improved significantly from baseline to follow-up across diagnoses 20.59 (0.56) to 15.76 (0.56). BIPQ improved from: 22.30 (0.43) to 14.88 (0.47) and EQ-5D-5L: 0.715 (0.01) to 0.779 (0.01)), all P<0.001. CONCLUSIONS: Across disorders, the novel approach was associated with high acceptability and clinically important improvements in functional levels, illness perception, and health status. As the concentrated micro-choice based treatment format might have the potential to change the way we deliver rehabilitation across diagnoses, we suggest to proceed with a controlled trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT05234281.

Concentrated transdiagnostic and cross-disciplinary micro-choice based group treatment for patients with depression and with anxiety leads to lasting improvements after 12 months: a pilot study.

BACKGROUND: A concentrated transdiagnostic and micro choice-based group treatment for patients with depression and anxiety has previously shown to yield significant reduction in symptoms and increased level of functioning from pre to 3-month follow-up. In the present study, we report the results after 12 months follow-up. METHODS: This was a non-randomized clinical intervention pilot study, conducted in line with a published protocol. Sixty-seven consecutively referred patients, aged 19-47 (mean age 32.5, SD = 8.0) were included and completed treatment. All had a severity of their problems that entitled them to care in the specialist public mental health care. Self-reported age at onset of symptoms was 17.6 (SD = 7.9) years. Mean number of prior treatment courses was 3.5 (SD = 3.3; range 0-20). The main objective was to assess the treatment effectiveness by questionnaires measuring relevant symptoms at pre-treatment, 7 days-, 3 months-, 6 months- and at 12-months follow-up. RESULTS: Validated measures of functional impairment (WSAS), depression (PHQ9), anxiety (GAD7), worry (PSWQ), fatigue (CFQ), insomnia (BIS) and illness perception (BIPQ) improved significantly (p < .0005) from before treatment to 12 months follow-up, yielding mostly large to extremely large effect sizes (0.89-3.68), whereas some moderate (0.60-0.76). After 12 months, 74% report an overall improvement in problems related to anxiety and depression. Utilization of specialist, public and private mental health care was reported as nonexistent or had decreased for 70% of the patients at 12-month follow up. CONCLUSIONS: The concentrated, micro-choice based group treatment approach yielded a highly clinically significant reduction in a wide range of symptoms already one week after treatment, and the positive results persisted at 12-month follow-up. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05234281, first posted date 10/02/2022.

Patient adherence as a predictor of acute and long-term outcomes in concentrated exposure treatment for difficult-to-treat obsessive-compulsive disorder.

BACKGROUND: Exposure and response prevention (ERP) is considered the first-line psychotherapy for obsessive-compulsive disorder (OCD). Substantial research supports the effectiveness of ERP, yet a notable portion of patients do not fully respond while others experience relapse. Understanding poor outcomes such as these necessitates further research. This study investigated the role of patient adherence to ERP tasks in concentrated exposure treatment (cET) in a sample who had previously not responded to treatment or relapsed. METHOD: The present study included 163 adults with difficult-to-treat OCD. All patients received cET delivered during four consecutive days. Patients' treatment adherence was assessed using the Patient EX/RP Adherence Scale (PEAS-P) after the second and third day of treatment. OCD severity was evaluated at post-treatment, 3-month follow-up, and 1-year follow-up by independent evaluators. RESULTS: PEAS-P scores during concentrated treatment were associated with OCD-severity at post-treatment, 3-month follow-up, and 1-year follow-up. Moreover, PEAS-P scores predicted 12-month OCD severity adjusting for relevant covariates. Adherence also predicted work- and social functioning at 1-year follow-up. CONCLUSIONS: These results indicate that ERP adherence during the brief period of cET robustly relates to improvement in OCD symptoms and functioning in both the short and long term. Assessing adherence might identify patients at risk of poor outcomes, while improving adherence may enhance ERP for treatment resistant patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02656342.

The Bergen 4-day treatment for panic disorder: adapting to COVID-19 restrictions with a hybrid approach of face-to-face and videoconference modalities.

BACKGROUND: The Bergen 4-day treatment (B4DT) is a concentrated exposure-based therapy that has been shown to be effective in the treatment of anxiety disorders. The current study sought to examine the effectiveness of B4DT for panic disorder (PD), when delivered with a combination of face-to-face sessions and videoconferencing. METHODS: Treatment was delivered to 50 patients from April 2020 to May 2021. Because of regulations during the pandemic, a significant portion of the treatment was conducted via videoconference. The primary outcome measure was the clinician-rated Panic Disorder Severity Scale (PDSS), and secondary measures included patient-rated symptoms of panic disorder, agoraphobia, generalized anxiety, depression, and treatment satisfaction. Changes in symptom levels over time were estimated using multilevel models. RESULTS: Patients showed a significant reduction in clinician-rated symptoms of panic disorder (Measured by PDSS) from before treatment to post treatment (d = 2.18) and 3-month follow-up (d = 2.01). At three months follow-up 62% of patients were classified as in remission, while 70% reported a clinically significant response. We also found a reduction in symptoms of depression and generalized anxiety, and the patients reported high satisfaction with the treatment. CONCLUSION: The current study suggests that B4DT delivered in a combination of videoconference and face-to-face meetings may be a useful treatment approach. As the study is uncontrolled, future studies should also include more strictly designed investigations.

The Bergen 4-day treatment for panic disorder: implementation in a rural clinical setting.

INTRODUCTION: The Bergen 4-Day Treatment (B4DT) is a concentrated treatment with individually tailored exposure exercises. The format has shown promising results in the treatment of panic disorder. AIM: The aim of the current study was to investigate the effectiveness of the B4DT in a large sample in a rural clinical setting. METHOD: Fifty-eight patients with panic disorder were consecutively included using an open trial design. The primary outcome measure was the Panic Disorder Severity Scale. The Generalized Anxiety Disorder-7 and the Patient Health Questionnaire-9 were used as secondary outcome measures. Assessments were conducted at pretreatment, posttreatment, and 3-month follow-up. Treatment satisfaction was measured at posttreatment using the Client Satisfaction Questionnaire-8. RESULTS: There was a significant reduction in symptoms of panic disorder from pre- to posttreatment (d = 3.36) and from pretreatment to follow-up (d = 3.63). At posttreatment and follow-up, 72.4% and 81.0% of patients, respectively, were classified as in remission. Patients reported high treatment satisfaction, and there were significant reductions in symptoms of generalized anxiety and depression. CONCLUSION: The results from the current study replicated the findings from previous studies using a larger sample size. The findings indicate that the B4DT is a promising treatment format for panic disorder. The study also demonstrated that the treatment format can be successfully implemented in new rural clinics.

An overview of the first 5 years of the ENIGMA obsessive-compulsive disorder working group: The power of worldwide collaboration.

Neuroimaging has played an important part in advancing our understanding of the neurobiology of obsessive-compulsive disorder (OCD). At the same time, neuroimaging studies of OCD have had notable limitations, including reliance on relatively small samples. International collaborative efforts to increase statistical power by combining samples from across sites have been bolstered by the ENIGMA consortium; this provides specific technical expertise for conducting multi-site analyses, as well as access to a collaborative community of neuroimaging scientists. In this article, we outline the background to, development of, and initial findings from ENIGMA's OCD working group, which currently consists of 47 samples from 34 institutes in 15 countries on 5 continents, with a total sample of 2,323 OCD patients and 2,325 healthy controls. Initial work has focused on studies of cortical thickness and subcortical volumes, structural connectivity, and brain lateralization in children, adolescents and adults with OCD, also including the study on the commonalities and distinctions across different neurodevelopment disorders. Additional work is ongoing, employing machine learning techniques. Findings to date have contributed to the development of neurobiological models of OCD, have provided an important model of global scientific collaboration, and have had a number of clinical implications. Importantly, our work has shed new light on questions about whether structural and functional alterations found in OCD reflect neurodevelopmental changes, effects of the disease process, or medication impacts. We conclude with a summary of ongoing work by ENIGMA-OCD, and a consideration of future directions for neuroimaging research on OCD within and beyond ENIGMA.

The Bergen 4-day treatment for panic disorder: replication and implementation in a new clinic.

BACKGROUND: Bergen 4-day treatment (B4DT) is a concentrated exposure-based treatment (cET), where the patient receives concentrated, individually tailored cognitive behavioral therapy (CBT) during four consecutive days. Previous findings have indicated that B4DT could be a promising treatment for panic disorder (PD). AIM: The aim of the present study was to evaluate the implementation of B4DT for panic disorder with- and without agoraphobia, at a new clinic. This is the first replication study for B4DT on panic disorder. METHOD: Thirty consecutively recruited patients with PD were included in an open trial design. Assessment of symptoms of panic disorder were measured with Panic Disorder Severity Scale (PDSS), while symptoms of generalized anxiety were assessed by Generalized Anxiety Disorder-7 (GAD-7) and depressive symptoms by Patient Health Questionnaire (PHQ-9) pre-treatment, post-treatment and at 3-month follow-up. Treatment satisfaction was measured with Client Satisfaction Questionnaire (CSQ-8) post-treatment. RESULTS: The results showed a significant reduction in symptom severity from pre-treatment to post-treatment (d = 4.32), and at 3-month follow-up (d = 4.91). The proportion of patients classified as fulfilling the criteria for remission was 80.0% at post-treatment and 86.7% at follow up. There was a significant reduction in symptoms of depression and generalized anxiety. Treatment satisfaction was high and none of the patients dropped out. CONCLUSION: The current study replicated the results from the original study and indicate that the treatment can be successfully implemented at new clinics. B4DT may be a promising treatment for panic disorder and comorbid symptoms of generalized anxiety and depression. Larger and more controlled studies are needed to establish the efficacy of B4DT for panic disorder.

Personality traits and hardiness as risk- and protective factors for mental distress during the COVID-19 pandemic: a Norwegian two-wave study.

BACKGROUND: Several risk factors for anxious-depressive symptomatology during the COVID-19 pandemic have been established. However, few studies have examined the relationship between personality traits, hardiness, and such symptomatology during the pandemic. These constructs might serve as risk- and/or protective factors for such mental distress through the pandemic. METHODS: A sample of 5783 Norwegians responded to a survey at two time points within the first year of the pandemic. The first data collection was in April 2020 (T1) and the second in December 2020 (T2). Measures included the Ten-Item Personality-Inventory, the Revised Norwegian Dispositional Resilience Scale, and the Patient Health Questionnaire Anxiety and Depression Scale. Analyses were performed using Pearson's correlations, multiple linear regression, and a moderation analysis. RESULTS: Anxious-depressive symptomatology in early phases (T1) of the pandemic was the strongest predictor for the presence of such symptomatology 9 months after the outbreak (T2). Personality and hardiness correlated significantly with mental distress at T1 and T2. Personality traits explained 5% variance in symptoms when controlling for age, gender, solitary living, negative economic impact, and mental distress at baseline. Higher neuroticism predicted higher mental distress, whereas higher conscientiousness and extraversion predicted less mental distress. Hardiness did not explain variance in outcome beyond personality traits. Hardiness did not significantly moderate the relationship between neuroticism and mental distress. CONCLUSION: Individuals with high levels of neuroticism had greater difficulties adapting to the circumstances of the COVID-19 pandemic and were more prone to mental distress. Contrastingly, higher conscientiousness and extraversion may have served as protective factors for mental distress during the pandemic. The current findings might aid identification of vulnerable individuals and groups. Consequently, preventive interventions could be offered to those who need it the most.

Concentrated transdiagnostic and cross-disciplinary group treatment for patients with depression and with anxiety: a pilot study.

BACKGROUND: A number of treatment approaches have shown efficacy for depression and/or anxiety, yet there is a paucity of research on potentially cost-effective concentrated approaches. Based on our previous experience with concentrated treatment in disorders such as Obsessive-Compulsive Disorder and chronic fatigue, we proposed that this novel approach could be useful for other conditions, including depression and/or anxiety. As a pre-requisite for a future randomized controlled trial, the aim of this study was to investigate the acceptability, satisfaction and effectiveness of a transdiagnostic, interdisciplinary group treatment delivered during 5 consecutive days to groups of 6-10 patients with depression and/or anxiety. METHODS: This was a non-randomized clinical intervention pilot study in line with a published protocol. Forty-two consecutively referred patients, aged 19-47 (mean age 31.7, SD = 8.12) were included and completed treatment. All had a severity of their problems that entitled them to care in the specialist public mental health care. Self-reported age when the symptoms became a problem was 20.9 years. Mean number of prior treatment courses was 2.77 (SD = 2.19; range 0-8). Acceptability was defined as the proportion of eligible patients who accepted and completed the treatment. Satisfaction was evaluated by Client Satisfaction Questionnaire-8. Secondary objectives were to assess the treatment effectiveness by questionnaires at pre-treatment, seven days post-treatment and three months follow-up. RESULTS: The treatment was highly acceptable (91.3% accepted, all completed), and patients were highly satisfied with the treatment, including the amount. Functional impairment, as measured by Work and Social Adjustment Scale (WSAS) improved significantly (p < .0005) from "severe" (mean 25.4 SD = 6.59) to "less severe" (mean 13.37, SD = 9.43) at 3 months follow-up. Using the Generalized Anxiety Disorder Scale (GAD-7) and the Patient Health Questionnaire (PHQ-9), the effect sizes at 3 months follow-up were 1.21 for anxiety and 1.3 for depression. More than 80% reported reduced utilization of mental health care, and 67% had not used, or had used the family doctor less, for anxiety or depression. 52% had not used, or had reduced, medication for their disorder. CONCLUSIONS: The concentrated, interdisciplinary treatment approach yielded promising results. Long-term follow up is warranted. TRIAL REGISTRATION: This study is registered in Clinical Trials, identifier NCT05234281 and approval date 09/02/2022.

Mental health symptoms during the first months of the COVID-19 outbreak in Norway: A cross-sectional survey study.

BACKGROUND: The COVID-19 pandemic has led to major social and economic changes that could impact public mental health. The main aim of the current study was to investigate mental health in Norway during the COVID-19 outbreak (since the first confirmed case on 26 February 2020). METHODS: The results are from the first wave of the data collection (1 April-2 June 2020), which took place during the outbreak along with its initial restrictions. A total of 19,372 (11,883 students) people participated in a cross-sectional web-based survey. RESULTS: A total of 21.8% scored above the cut-off for depression and 23.7% for anxiety. Severity of symptoms was associated with the accumulation of risk factors, such as possible/confirmed infection for oneself or one's family, female/other sex, students, having mental health problems, increased use of tobacco, increased use of alcohol, less exercise, losing one's job, suffering economic impact and lower education. CONCLUSIONS: COVID-19 could have a negative association with public mental health, especially for certain risk groups. Future data-collection waves will provide further insight into the development of symptoms following the pandemic.

Nordic OCD & Related Disorders Consortium: Rationale, design, and methods.

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric disorder, yet its etiology is unknown and treatment outcomes could be improved if biological targets could be identified. Unfortunately, genetic findings for OCD are lagging behind other psychiatric disorders. Thus, there is a pressing need to understand the causal mechanisms implicated in OCD in order to improve clinical outcomes and to reduce morbidity and societal costs. Specifically, there is a need for a large-scale, etiologically informative genetic study integrating genetic and environmental factors that presumably interact to cause the condition. The Nordic countries provide fertile ground for such a study, given their detailed population registers, national healthcare systems and active specialist clinics for OCD. We thus formed the Nordic OCD and Related Disorders Consortium (NORDiC, www.crowleylab.org/nordic), and with the support of NIMH and the Swedish Research Council, have begun to collect a large, richly phenotyped and genotyped sample of OCD cases. Our specific aims are geared toward answering a number of key questions regarding the biology, etiology, and treatment of OCD. This article describes and discusses the rationale, design, and methodology of NORDiC, including details on clinical measures and planned genomic analyses.

The Bergen 4-day treatment for OCD: four years follow-up of concentrated ERP in a clinical mental health setting.

There are few long-term follow-up studies on psychological treatment of anxiety disorders carried out in clinical mental health settings, so called effectiveness studies. The present paper presents a four year follow-up of patients with obsessive-compulsive disorder treated by the Bergen 4-day treatment (B4DT), a concentrated form of exposure and response prevention (ERP). A total of 77 obsessive-compulsive disorder (OCD) patients received treatment during four consecutive days and were assessed with the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) pre, post, and at follow-ups after 3 and 6 months, and 4 years post-treatment. The Y-BOCS mean score changed from 25.9 at pre- to 10.0 post-treatment and 9.9 at long-term follow-up. The proportion fulfilling the strict international consensus criteria for remission was 73% at post-treatment and 69% at follow-up. When taking declining rate, attrition rate, remission, relapse, and further improvement during the follow-up period into account, 72% were recovered on a long-term basis. A comparison with previously published effectiveness studies of ERP indicated that the 4-day treatment yielded significantly higher proportions of remission at post-treatment and recovery at follow-up, as well as within-group effect size on the Y-BOCS. The implications of these results are discussed.

Does Family Accommodation Predict Outcome of Concentrated Exposure and Response Prevention for Adolescents?

Findings suggest that increased levels of family accommodation are associated with a poorer treatment outcome in obsessive-compulsive disorder (OCD). A concentrated treatment format, the Bergen 4-day treatment (B4DT), has previously demonstrated promising results in the treatment of adolescents with OCD. The present paper examined changes in family accommodation and investigated whether family accommodation predicted outcome, in a sample of 63 adolescents (age range 11-18) participating in the B4DT. There were significant reductions on CY-BOCS and FAS from pre- to post-treatment and from pre-treatment to follow-up (p < 0.001), with large within-group effect sizes on both measures. Pre-treatment levels of symptom severity or family accommodation was not found to predict outcome at post-treatment or at follow-up. Less OCD-related functional impairment at pre-treatment predicted a better outcome at both post-treatment and follow-up. The findings suggest that the B4DT significantly reduces OCD-symptoms regardless of pre-treatment levels of family accommodation or OCD severity.

Dispositional resilience in treatment-seeking patients with obsessive-compulsive disorder and its association with treatment outcome.

There is a lack of research on the relation between obsessive-compulsive disorder (OCD) and resilience. Dispositional resilience, as described and defined in literature on hardiness, consists of three facets, namely beliefs about having control in everyday living, having a sense of purpose or commitment, and a positive attitude toward challenges. This study explores associations between dispositional resilience (measured with the Dispositional Resilience Scale (DRS-15-R)), symptom severity, and treatment outcome in a sample of 89 patients treated with concentrated exposure therapy (cET), and compares the findings with scores from two reference groups (students and soldiers). The patient group had significantly lower resilience scores than the two reference groups. Weak correlations were observed between dispositional resilience and OCD symptoms. Differences in dispositional resilience were weakly related to remission status at follow-up (odds ratio of 1.11). Furthermore, resilience improved from pre- to post-treatment (Cohen's d of 0.65). Our results imply that patients' initial resilience score does not hinder nor facilitate treatment effects to a great extent in this format of ERP treatment.

Successfully treating 90 patients with obsessive compulsive disorder in eight days: the Bergen 4-day treatment.

BACKGROUND: Oslo University Hospital, Norway, had by autumn 2016, accumulated a waiting list of 101 patients with obsessive-compulsive disorder (OCD) who had a legal right to receive treatment by a specialized OCD team. In this challenging situation, the Bergen OCD-team suggested to solve the problem by offering all patients an option for the rapid Bergen 4-day treatment (B4DT). The B4DT is an individual treatment delivered during four consecutive days in a group of six patients with the same number of therapists. The approach has previously shown a post-treatment response rate of 90% and a 3-month remission rate of 70%. METHODS: Ninety-seven of the wait-list patients were available for the scheduled time slots, and 90 received the 4-day format during 8 days (45 patients each week). The therapists were recruited from 22 different specialized OCD-teams from all over Norway, and 44 (68%) had not previously delivered the 4-day format. RESULTS: Post-treatment; 91.1% of the patients were classified as responders, and 72.2% were in remission. At 3-month follow-up; 84.4 were classified as responders and the remission rate was 67.7%. Oslo University Hospital now offers the 4-day treatment as standard treatment for OCD. CONCLUSIONS: We conclude that the B4DT is an acceptable and potentially effective OCD-treatment.

Sleep disturbances in treatment-seeking OCD-patients: Changes after concentrated exposure treatment.

Research indicates that patients with Obsessive Compulsive Disorder (OCD) frequently suffer from comorbid sleep difficulties, and that these difficulties often are not clinically recognized and diagnosed. There has been limited research investigating if comorbid sleep difficulties impair treatment outcome for OCD and if the sleep difficulties change following OCD-treatment. Thirty-six patients with obsessive compulsive disorder underwent concentrated exposure treatment delivered in a group over four consecutive days and were assessed with measures of OCD, depressive symptoms and sleep disturbance at three different time points (pre, post and 6 months follow-up). The sample was characterized by a high degree of comorbidity with other psychiatric disorders. At pre-treatment nearly 70% of the patients reported sleep difficulties indicative of primary insomnia. The results showed that patients had large reductions of OCD-symptoms as well as significant improvements in sleep disturbance assessed after treatment, and that these improvements were maintained at follow-up. Sleep disturbance did not impair treatment outcome, on the contrary patients with higher degree of sleep disturbance at pre-treatment had better outcome on OCD-symptoms after treatment. The results indicated that the majority of the OCD sample suffered from sleep disturbances and that these sleep disturbances were significantly reduced following adequate treatment of OCD without specific sleep interventions. However, a proportion of the patients suffered from residual symptoms of insomnia after treatment.

Concentrated ERP Delivered in a Group Setting: A Replication Study.

BACKGROUND: In a previous effectiveness study (Havnen et al., 2014), 35 obsessive compulsive disorder (OCD) patients underwent Concentrated Exposure Treatment (cET), which is a newly developed group treatment format delivered over four consecutive days. AIMS: The primary aims of the present study were to evaluate the treatment results for a new sample of OCD patients receiving the cET treatment approach and to replicate the effectiveness study described in Havnen et al. (2014). METHOD: Forty-two OCD patients underwent cET treatment. Treatment was delivered by different therapists than in Havnen et al. (2014), except for two groups led by the developers of the treatment. Assessments of OCD symptom severity, treatment satisfaction, and occupational impairment were included. RESULTS: The results showed a significant reduction in Yale-Brown Obsessive Compulsive Scale scores from pre-treatment to post-treatment, which was maintained at 6-month follow-up. At post-treatment, 74% of the sample was remitted; at 6-month follow-up, 60% were recovered. The sample showed a very high degree of overall treatment satisfaction. The results from the present study were statistically compared with those obtained in the previous study. The analyses showed that the study samples had comparable demographic data and equal application of treatment. The outcome of the present and original study did not differ significantly on primary and secondary outcome measures. CONCLUSIONS: This study shows that cET was successfully replicated in a new patient sample treated by different therapists than the original study. The results indicate that cET is well accepted by the patients, and the potential for dissemination is discussed.

A Burden of Rare Copy Number Variants in Obsessive-Compulsive Disorder.

Current genetic research on obsessive-compulsive disorder (OCD) supports contributions to risk specifically from common single nucleotide variants (SNVs), along with rare coding SNVs and small insertion-deletions (indels). The contribution to OCD risk from large, rare copy number variants (CNVs), however, has not been formally assessed at a similar scale. Here we describe an analysis of rare CNVs called from genotype array data in 2,248 deeply phenotyped OCD cases and 3,608 unaffected controls from Sweden and Norway. We found that in general cases carry an elevated burden of large (>30kb, at least 15 probes) CNVs (OR=1.12, P=1.77×10-3). The excess rate of these CNVs in cases versus controls was around 0.07 (95% CI 0.02-0.11, P=2.58×10-3). This signal was largely driven by CNVs overlapping protein-coding regions (OR=1.19, P=3.08×10-4), particularly deletions impacting loss-of-function intolerant genes (pLI>0.995, OR=4.12, P=2.54×10-5). We did not identify any specific locus where CNV burden was associated with OCD case status at genome-wide significance, but we noted non-random recurrence of CNV deletions in cases (permutation P = 2.60×10-3). In cases where sufficient clinical data were available (n=1612) we found that carriers of neurodevelopmental duplications were more likely to have comorbid autism (P<0.001), and that carriers of deletions overlapping neurodevelopmental genes had lower treatment response (P=0.02). The results demonstrate a contribution of large, rare CNVs to OCD risk, and suggest that studies of rare coding variation in OCD would have increased power to identify risk genes if this class of variation were incorporated into formal tests.