Reduced resting-state functional connectivity between insula and inferior frontal gyrus and superior temporal gyrus in hoarding disorder.

Background: Hoarding disorder (HD) is characterized by cognitive control impairments and abnormal brain activity in the insula and anterior cingulate cortex (ACC) during disposal of personal items or certain executive function tasks. However, whether there are any changes in resting-state functional connectivity of the insula and ACC remains unclear. Methods: A total of 55 subjects, including 24 patients with HD and 31 healthy controls (HCs), participated in the study. We acquired resting-state functional magnetic resonance imaging data and examined group differences in functional connectivity from the insula and ACC in whole-brain voxels. Results: In patients with HD, functional connectivity was significantly lower between the right insula and right inferior frontal gyrus (IFG) and left superior temporal gyrus (STG) compared to HCs. There was no correlation between these connectivities and HD symptoms. Conclusions: Although the clinical implication is uncertain, our results suggest that patients with HD have resting-state functional alterations between the insula and IFG and STG, corresponding with the results of previous fMRI studies. These findings provide new insight into the neurobiological basis of HD.

Psychological treatments for mental health symptoms associated with COVID-19 infection: A scoping review.

The aim of this scoping review was to synthesize published studies and ongoing clinical trials of psychological interventions for mental health problems associated with COVID-19 infection. The study protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews. We conducted systematic searches for studies published or registered between January 2020 and October 2022 using eight scientific databases and clinical trial registries, which identified 40 complete published studies and 53 ongoing clinical trials. We found that most studies were randomized controlled trials (74%) while the remaining used study designs of lower methodological quality. Most studies investigated interventions for acute COVID-19 patients (74%) and others explored post-COVID conditions (PCC) or recovered patients. Cognitive and behavioral therapies were the main intervention approaches (31%), followed by multidisciplinary programs (21%) and mindfulness (17%). The most frequently evaluated outcomes were anxiety (33%), depression (26%), quality of life (13%), and insomnia (10%). No studies on youths, older people, or marginalized communities were found. These findings summarize the burgeoning research on a range of psychological interventions for individuals infected with COVID-19. However, the field is in its infancy and further research to develop an evidence base for targeted care is necessary. The gaps identified in the current study also highlight the need for more research on youths, older people, and members of marginalized communities, and PCC patients. It is important to ascertain interventions and delivery strategies that are not only effective and affordable but also allow high scalability and accessibility.

Incidence of post-COVID psychiatric disorders according to the periods of SARS-CoV-2 variant dominance: The LIFE study.

This retrospective cohort study examined the incidence of post-COVID psychiatric disorders in older adults according to hospitalization status and SARS-CoV-2 variant period in Japan. Claims data, COVID-19 case-related information, and vaccination records were obtained from three Japanese municipalities. We identified individuals aged ≥65 years who had COVID-19 or other respiratory tract infection (RTI) between March 2021 and December 2022. Participants were categorized into non-hospitalized and hospitalized patients, and the study period was divided into the Alpha (March to May 2021), Delta (June to December 2021), Omicron BA.1/BA.2 (January to June 2022), and Omicron BA.5 (July to December 2022) periods. Modified Poisson regression analyses were performed to estimate the incidence rate ratios (IRRs) for the occurrence of psychiatric disorders (organic mental disorders, psychotic disorders, mood disorders, anxiety disorders, and insomnia) three months after COVID-19 (reference: other RTI). For overall psychiatric disorders, we analyzed 19,489 non-hospitalized patients (COVID-19: 6,728, Other RTI: 12,761) and 2925 hospitalized patients (COVID-19: 1,036, Other RTI: 1889). When compared with other RTI cases, COVID-19 cases had significantly lower IRRs for overall psychiatric disorders in both non-hospitalized (IRR: 0.59, P < 0.001) and hospitalized cases (IRR: 0. 83, P = 0.045) during the Omicron BA.1/BA.2 period, but only in non-hospitalized cases (IRR: 0.45, P < 0.001) during the Omicron BA.5 period. The incidences of the individual post-COVID psychiatric disorders varied according to disorder type, hospitalization status, and SARS-CoV-2 variant period. These findings provide a foundation for further research to explore these variations and improve the provision of psychiatric care in future epidemics.

Associations between COVID-19 vaccination and incident psychiatric disorders after breakthrough SARS-CoV-2 infection: The VENUS Study.

BACKGROUND: The associations between COVID-19 vaccination and post-COVID psychiatric disorders are unclear. Furthermore, it is uncertain if these associations differ depending on the dominant SARS-CoV-2 variant at the time of infection. This retrospective cohort study aimed to clarify the associations between COVID-19 vaccination and incident psychiatric disorders after breakthrough infection according to the different variant periods in Japan. METHODS: Medical claims data, COVID-19 case-related information, and vaccination records were collected from three Japanese municipalities. The study population comprised public insurance enrollees aged ≥65 years who developed COVID-19 between June 2021 and December 2022. The study exposure was each participant's vaccination status 14 days before infection, and the outcomes were the occurrence of psychiatric disorders within three months of infection. Multivariable logistic regression analyses were performed to calculate the odds ratios (ORs) and 95 % confidence intervals (CIs) of vaccination for the occurrence of psychiatric disorders. Analyses were conducted for the Delta period (June to December 2021), Omicron BA.1/BA.2 period (January to June 2022), and Omicron BA.5 period (July to December 2022). RESULTS: We analyzed 270 participants (vaccinated: 149) in the Delta period, 2,963 participants (vaccinated: 2,699) in the Omicron BA.1/BA.2 period, and 7,723 participants (vaccinated: 7,159) in the Omicron BA.5 period. During the Delta period, vaccinated participants had significantly lower odds for psychotic disorders (OR: 0.23, 95 % CI: 0.06-0.88, P = 0.032) than unvaccinated participants. During the Omicron BA.5 period, vaccinated participants had significantly lower odds for organic mental disorders (OR: 0.54, 95 % CI: 0.30-0.95, P = 0.033), psychotic disorders (OR: 0.31, 95 % CI: 0.19-0.53, P < 0.001), mood disorders (OR: 0.53, 95 % CI: 0.29-0.99, P = 0.046), and insomnia (OR: 0.48, 95 % CI: 0.32-0.72, P < 0.001) than unvaccinated participants. There were no significant differences in psychiatric disorders between the vaccinated and unvaccinated groups during the Omicron BA.1/BA.2 period. CONCLUSIONS: This is the first study to demonstrate that the associations between COVID-19 vaccination and post-COVID psychiatric disorders vary among the different variant periods. Future studies on these associations should be conducted with consideration to the prevalent circulating variants.

Decision-making deficits in obsessive-compulsive disorder are associated with abnormality of recency and response consistency parameter in prospect valence learning model.

Background: Patients with obsessive-compulsive disorder (OCD) have deficits in decision-making in the Iowa Gambling Task (IGT). However, no study has investigated the parameters of the prospect valence learning (PVL) model in the IGT for OCD. Aims: This study aimed to investigate deficits in decision-making in OCD using the PVL model and identify whether the parameters of the PVL model were associated with obsessive-compulsive severity. Methods: Forty-seven medication-free patients with OCD were compared with 47 healthy controls (HCs). Decision-making was measured using the total net and block net scores of the IGT. A PVL model with a decay-reinforcement learning rule (PVL-DecayRI) was used to investigate the parameters of the model. Correlation analysis was conducted between each parameter of the PVL-DecayRL and obsessive-compulsive symptoms. Results: The total net score of patients with OCD was significantly lower than that of the HCs. The block net scores of the OCD group did not differ across the five blocks, whereas in the HCs, the fifth block net score was significantly higher than the block net scores of the first and second blocks. The values of the recency and response consistency parameters of the PVL-DecayRI in patients with OCD were significantly lower than those in HCs. The recency parameter positively correlated with the Y-BOCS obsessive score. Meanwhile, there was no correlation between consistency parameter values and symptom severity in OCD. Conclusion: Our detailed analysis of the decision-making deficit in OCD suggests that the most recent outcome has a small influence on the expectancy of prospect valence, as indicated by the lower recency parameter, and is characterized by more impulsive choices, as indicated by the lower consistency parameter.

Posterior cingulate cortex spontaneous activity associated with motor response inhibition in patients with obsessive-compulsive disorder: A resting-state fMRI study.

Recent evidence suggests that broad brain regions, not limited to the fronto-striato-thalamo-cortical circuit, play an important role in motor response inhibition. However, it is still unclear which specific key brain region is responsible for impaired motor response inhibition observed in obsessive-compulsive disorder (OCD). We calculated the fractional amplitude of low-frequency fluctuations (fALFF) and measured response inhibition ability using the stop-signal task in 41 medication-free patients with OCD and 49 healthy control (HC) participants. We explored the brain region that shows different association between the fALFF and the ability of motor response inhibition. Significant differences in fALFF associated with the ability of motor response inhibition were identified in dorsal posterior cingulate cortex (PCC). There was a positive correlation between increased fALFF in the dorsal PCC and impaired motor response inhibition in OCD. In the HC group, there was a negative correlation between the two variables. Our results suggest that the magnitude of resting-state blood oxygen level-dependent oscillation of the dorsal PCC is a key brain region for the underlying mechanisms of impaired motor response inhibition in OCD. Future studies should examine whether this characteristic of dorsal PCC affects other large-scale networks responsible for motor response inhibition of OCD.

Gyrification of the medial and lateral orbitofrontal cortex in first-degree relatives of patients with obsessive-compulsive disorder.

Gyrification patterns reflect early neurodevelopment and could be highly heritable. While some discrepant results have been reported, the most consistent finding was that patients with obsessive-compulsive disorder showed altered gyrification patterns in the orbitofrontal cortex. Nevertheless, no study has investigated the alterations in gyrification in unaffected first-degree relatives of patients with obsessive-compulsive disorder. We measured local gyrification by the FreeSurfer software in 23 unaffected first-degree relatives of patients with obsessive-compulsive disorder and 52 healthy control participants. We explored differences in the local gyrification index using vertex-wise whole-brain analysis and a region of interest-based approach in the medial and lateral orbitofrontal cortex. There was no significant difference in the local gyrification index between the 2 groups in the vertex-wise whole-brain analysis. Region of interest analyses showed that, compared with healthy controls, first-degree relatives showed significantly reduced local gyrification index in the left medial and lateral orbitofrontal cortex. A negative correlation was observed between the reduced local gyrification index in lateral orbitofrontal cortex and the subclinical anxiety scores of first-degree relatives. Our results showed that first-degree relatives of patients with obsessive-compulsive disorder had an altered local gyrification index in the orbitofrontal cortex. Especially, reduced local gyrification index in lateral orbitofrontal cortex associated with subclinical anxiety symptom could be a potential neurodevelopmental marker for the illness onset.

Survey of psychiatric symptoms among inpatients with COVID-19 using the Diagnosis Procedure Combination data and medical records in Japan.

Physical symptoms such as fatigue and muscle weakness, and psychiatric symptoms like depression and anxiety are considered as complications and sequelae of COVID-19. This epidemiological study investigated the actual status of psychiatric symptoms and disorders caused by COVID-19, from four major university hospitals and five general hospitals in Fukuoka Prefecture, Japan, having a population of 5 million. We conducted a survey of psychiatric disorders associated with COVID-19 using Diagnosis Procedure Combination (DPC) data and the psychiatric records of the hospitals. In the study period from January 2019 to September 2021, 2743 COVID-19 admissions were determined from DPC data across the nine sites. These subjects had significantly more anxiety, depression, and insomnia, and were receiving higher rates of various psychotropic medications than controls influenza and respiratory infections. A review of psychiatric records revealed that the frequency of organic mental illness with insomnia and confusion was proportional to the severity of COVID-19 infection and that anxiety symptoms appeared independent of infection severity. These results indicate that COVID-19 is more likely to produce psychiatric symptoms such as anxiety and insomnia than conventional infections.

Psychological treatments for the mental health symptoms among individuals infected with COVID-19: a scoping review protocol.

INTRODUCTION: Mental health symptoms such as depression, anxiety and sleep problems are commonly observed in individuals suffering from acute COVID-19 infection to post-COVID-19 syndrome. Studies have provided preliminary evidence for the efficacies of cognitive behavioural therapy, mindfulness-based interventions, acceptance and commitment therapy, and many other treatments for this population. Although there have been attempts to synthesise the literature on these psychological interventions, previous reviews have been limited in terms of the sources, symptoms and interventions that they included. Furthermore, most studies reviewed were conducted in early 2020, when COVID-19 had only recently been classified as a global pandemic. Since then, substantial research has been conducted. As such, we sought to provide an updated synthesis of the available evidence of treatments for the range of mental health symptoms associated with COVID-19. METHODS AND ANALYSIS: This scoping review protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. Systematic searches were carried out on scientific databases (PubMed, Web of Science, PsycINFO and Scopus) and clinical trial registries (ClinicalTrials.gov, WHO ICTRP, EU Clinical Trials Register and Cochrane Central Register of Controlled Trials) to identify studies that have or will assess the efficacy or any aspects of psychological treatment for acute to post-COVID-19 syndrome. The search was conducted on 14 October 2022 and identified 17 855 potentially eligible sources/studies published since 1 January 2020 (duplicates removed). Six investigators will independently carry out titles and abstract screening, full-text screening and data charting and the results will be summarised using descriptive statistics and narrative synthesis. ETHICS AND DISSEMINATION: Ethical approval is not required for this review. The results will be disseminated through a peer-reviewed journal, conference presentations and/or academic newspapers. This scoping review has been registered with Open Science Framework (https://osf.io/wvr5t).

Functional connectivity between pre-supplementary motor area and inferior parietal lobule associated with impaired motor response inhibition in first-degree relatives of patients with obsessive-compulsive disorder.

Previous studies have suggested that specific fronto-striatal circuits are associated with impaired motor response inhibition in patients with obsessive-compulsive disorder (OCD) and their relatives. However, no study has investigated the underlying resting-state network associated with motor response inhibition in the unaffected first-degree relatives of patients with OCD. We measured motor response inhibition using stop-signal task, and obtained resting-state fMRI in 23 first-degree relatives and 52 healthy control participants. We explored the group differences in the functional network from seed regions-of-interest (ROIs) associated with motor response inhibition abilities. We used the inferior frontal gyrus (IFG) and pre-supplementary motor area (pre-SMA) as seed-ROIs. A significant group difference was observed in functional connectivity between the pre-SMA and inferior parietal lobule. In the relative group, reduced functional connectivity between these areas was associated with a longer stop-signal reaction time. Additionally, relatives showed significantly greater functional connectivity between the IFG and SMA, precentral, and postcentral areas. Our results could provide new insights into the resting-state neural activity of the pre-SMA underlying impaired motor response inhibition of unaffected first-degree relatives. In addition, our results suggested that relatives have an altered connectivity of the sensorimotor region, similar to that of patients with OCD shown in previous literature.

The Impact of Gender and Age Differences and Infectious Disease Symptoms on Psychological Distress in Quarantined Asymptomatic or Mildly Ill COVID-19 Patients in Japan.

Quarantine imposed due to COVID-19 infection can exacerbate psychological distress, and it is important for a public mental health agency to identify factors that are predictive of high psychological distress in such situation. The aim of this study was to investigate whether gender, age, and the presence or absence of infectious disease symptoms affected psychological distress among asymptomatic or mildly ill COVID-19 patients who were quarantined. Participants were 436 asymptomatic or mildly symptomatic COVID-19-infected patients who were quarantined in a treatment facility between 1 May 2020 and 30 September 2021. We used Quantification Theory I analysis to investigate the effects of gender, age, and the nature of infectious disease symptoms on psychological distress. The results of the analysis showed that the contribution rate was 0.06. Among gender, age, presence of symptoms, and the nature of symptoms, age had the greatest effect on psychological distress, and being in one's teens to thirties was considered to exacerbate psychological distress the most. According to the results, the psychological distress of asymptomatic and mildly symptomatic COVID-19 patients isolated was affected by gender, age, and symptomology, especially due to age differences. However, the impact of these items on psychological distress was not considered significant.

Inverse Association Between Resting-State Putamen Activity and Iowa Gambling Task Performance in Patients With Obsessive-Compulsive Disorder and Control Subjects.

Background: Symptoms of obsessive-compulsive disorder (OCD) have been conceptualized as manifestations of decision-making deficits. Patients with OCD exhibit impairment during the decision-making process, as assessed by the Iowa Gambling Task (IGT). This impairment is independent of clinical severity and disease progression. However, the association between the decision-making deficit and resting-state brain activity of patients with OCD has not been examined. Methods: Fifty unmedicated patients with OCD and 55 matched control subjects completed IGT. Resting-state brain activity was examined using the fractional amplitude of low-frequency fluctuations (fALFFs). fALFF analysis focused on the slow-4 and 5 bands. Group comparisons were performed to determine the association between IGT performance and fALFFs. Results: There was a significant group difference in the association between the IGT total net score and slow-4 fALFFs in the left putamen (voxel height threshold of p < 0.001; cluster size threshold of p < 0.05; family wise error-corrected). Higher putamen slow-4 fALFFs were correlated with lower IGT scores for OCD patients (r = -0.485; p < 0.0005) and higher IGT scores for control subjects (r = 0.402; p < 0.005). There was no group difference in the association between the IGT total net score and slow-5 fALFFs. Conclusions: These findings in unmedicated patients demonstrate the importance of resting-state putamen activity for decision-making deficit associated with OCD, as measured by IGT. The inverse correlation may be explained by the hypersensitive response of the putamen in patients with OCD.

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

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

Abnormal white matter structure in hoarding disorder.

Although preliminary neuroimaging research suggests that patients with hoarding disorder (HD) show widespread abnormal task-related activity in the brain, there has been no research on alterations in the white matter tracts in these patients. The aim of this study was to investigate the characteristics of the major white matter tracts in patients with HD. Tract-based spatial statistics were used to search for white matter tract abnormalities throughout the brain in 25 patients with HD and 36 healthy controls. Post hoc analysis of regions of interest was performed to detect correlations with clinical features. Compared with the controls, patients with HD showed decreased fractional anisotropy and increased radial diffusivity in anatomically widespread white matter tracts. Post hoc analysis of regions of interest revealed a significant negative correlation between the severity of hoarding symptoms and fractional anisotropy in the left anterior limb of the internal capsule and a positive correlation between the severity of these symptoms and radial diffusivity in the right anterior thalamic radiation. Patients with HD showed a broad range of alterations in the frontal white matter tracts, including the frontothalamic circuit, frontoparietal network, and frontolimbic pathway. The findings of this study indicate associations between frontal white matter abnormalities related to the severity of hoarding symptoms in HD and the cortical regions involved in cognitive dysfunction. The insights provided would be useful for understanding the neurobiological basis of HD.

Increased functional connectivity between presupplementary motor area and inferior frontal gyrus associated with the ability of motor response inhibition in obsessive-compulsive disorder.

Recent evidence suggests that presupplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) play an important role in response inhibition. However, no study has investigated the relationship between these brain networks at resting-state and response inhibition in obsessive-compulsive disorder (OCD). We performed resting-state functional magnetic resonance imaging scans and then measured the response inhibition of 41 medication-free OCD patients and 49 healthy control (HC) participants by using the stop-signal task outside the scanner. We explored the differences between OCD and HC groups in the functional connectivity of pre-SMA and IFG associated with the ability of motor response inhibition. OCD patients showed a longer stop-signal reaction time (SSRT). Compared to HC, OCD patients exhibit different associations between the ability of motor response inhibition and the functional connectivity between pre-SMA and IFG, inferior parietal lobule, dorsal anterior cingulate cortex, insula, and anterior prefrontal cortex. Additional analysis to investigate the functional connectivity difference from the seed ROIs to the whole brain voxels revealed that, compared to HC, OCD exhibited greater functional connectivity between pre-SMA and IFG. Also, this functional connectivity was positively correlated with the SSRT score. These results provide additional insight into the characteristics of the resting-state functional connectivity of the regions belonging to the cortico-striato-thalamo-cortical circuit and the cingulo-opercular salience network, underlying the impaired motor response inhibition of OCD. In particular, we emphasize the importance of altered functional connectivity between pre-SMA and IFG for the pathophysiology of motor response inhibition in OCD.

Mental Health Difficulties and Countermeasures during the Coronavirus Disease Pandemic in Japan: A Nationwide Questionnaire Survey of Mental Health and Psychiatric Institutions.

The number of people with coronavirus disease (COVID-19) has been increasing worldwide. Anxiety about potential infection, fear of severe illness, death, economic problems, and loneliness and isolation brought on by social distancing are increasingly being experienced by people. Therefore, it is imperative to address and improve such mental health-related problems during COVID-19. We aimed to investigate the current mental health care and psychological intervention statuses related to COVID-19 in Japan. In a questionnaire survey, 55 of 69 (80%) mental health and welfare centers and 194 of 931 (21%) psychiatric institutions across Japan responded. COVID-19 patients, their family members, and the general public often consulted the mental health and welfare institutions through telephone. The questionnaire included various information of mental health difficulties related to COVID-19 such as the numbers and contents of the consultations, and the type of the interventions. The contents of consultation included psychological symptoms (anxiety, depression, insomnia, and alcohol problems) and psychosocial problems (interpersonal problems, prejudice, and discrimination). Overall, 9% of mental health and welfare centers provided psychological first aid as psychological intervention and 28% of consultations involved cases requiring urgent care. In Japan, consultations about COVID-19-related mental health problems occurred mainly in mental health and welfare centers. There is urgent need to establish a system that enables mental health triage and brief psychological interventions that are feasible in the centers.

Aberrant Resting-State Cerebellar-Cerebral Functional Connectivity in Unmedicated Patients With Obsessive-Compulsive Disorder.

Background: Although abnormality of cerebellar-cerebral functional connectivity at rest in obsessive-compulsive disorder (OCD) has been hypothesized, only a few studies have investigated the neural mechanism. To verify the findings of previous studies, a large sample of patients with OCD was studied because OCD shows possible heterogeneity. Methods: Forty-seven medication-free patients with OCD and 62 healthy controls (HCs) underwent resting-state functional magnetic imaging scans. Seed-based connectivity was examined to investigate differences in cerebellar-cerebral functional connectivity in OCD patients compared with HCs. Correlations between functional connectivity and the severity of obsessive-compulsive symptoms were analyzed. Results: In OCD, we found significantly increased functional connectivity between the right lobule VI and the left precuneus, which is a component of the default mode network (DMN), compared to HCs. However, there was no correlation between the connectivity of the right lobule VI-left precuneus and obsessive-compulsive severity. Conclusions: These findings suggest that altered functional connectivity between the cerebellum and DMN might cause changes in intrinsic large-scale brain networks related to the traits of OCD.

Impacts of Stressful Life Events and Traumatic Experiences on Onset of Obsessive-Compulsive Disorder.

Not a few patients with obsessive-compulsive disorder (OCD) have experienced events that affected the onset. The onset of OCD is not limited to the original meaning of trauma; rather, traumatic experiences such as unexpected exposure to contaminants or various stressful life events often cause the onset of OCD. It would be useful to understand the experiences surrounding the onset, including stressful life events and traumatic experiences, for comprehension of the pathophysiology of OCD. In the present study, we investigated the onset conditions of 281 patients with OCD and compared clinical characteristics among groups with or without stressful life events including traumatic experiences. As a result, 172 (61.2%) participants had experienced various stressful life events, and 98 (34%) participants had had traumatic experiences before the onset. Furthermore, the participants who had had stressful life events showed more contamination/fear symptoms compared with those without such life events. Meanwhile, the patients who had had specific traumatic experiences showed a tendency toward hoarding obsessions. To comprehend the pathophysiology of OCD, it is important to understand the stressful life events that precede its onset.

A voxel-based analysis of cerebral blood flow abnormalities in obsessive-compulsive disorder using pseudo-continuous arterial spin labeling MRI.

OBJECTIVE: To identify abnormalities of regional cerebral blood flow (rCBF) in individuals with obsessive-compulsive disorder (OCD) by conducting a voxel-based analysis of pseudo-continuous arterial spin labeling (pCASL) perfusion images. MATERIALS AND METHODS: This prospective study included 23 OCD patients (nine males, 14 females; age 21-62 years; mean ± SD 37.2 ± 10.7 years) diagnosed based on DSM-IV-TR criteria and 64 healthy controls (27 males, 37 females; age 20-64 years; mean ± SD 38.3 ± 12.8 years). Subjects were recruited from October 2011 to August 2017. Imaging was performed on a 3T scanner. Quantitative rCBF maps generated from pCASL images were co-registered and resliced with the three-dimensional T1-weighted images, and then spatially normalized to a brain template and smoothed. We used statistical nonparametric mapping to assess the differences in rCBF and gray matter volume between the OCD and control groups. The significance level was set at the p-value <0.05 with family-wise error rate correction for multiple comparisons. RESULTS: Compared to the control group, there were significant rCBF reductions in the right putamen, right frontal operculum, left midcingulate cortex, and right temporal pole in the OCD group. There were no significant between-group differences in the gray matter volume. CONCLUSION: The pCASL imaging noninvasively detected physiologically disrupted areas without structural abnormalities in OCD patients. The rCBF reductions observed in these regions in OCD patients could be associated with the pathophysiology of OCD.

Clinical characteristics of hoarding disorder in Japanese patients.

Previous studies have reported clinical characteristics of hoarding disorder (HD), such as early onset, a chronic course, familiality, high unmarried rate, and high rates of comorbidities. However, clinical research targeting Japanese HD patients has been very limited. As a result, there is a low recognition of HD in Japan, leading to insufficient evaluation and treatment of Japanese HD patients. The aim of the current study was to delineate the clinical characteristics of Japanese HD patients. Thirty HD patients, 20 obsessive-compulsive disorder (OCD) patients, and 21 normal controls (NC) were targeted in this study. The HD group had a tendency toward higher familiality, earlier onset, and longer disease duration compared to the OCD group. In addition, the HD group showed a significantly higher unmarried rate than the NC group. The top two comorbidities in the HD group were major depressive disorder (56.7%) and attention-deficit/hyperactivity disorder (26.7%). The HD group had significantly higher scores on hoarding rating scales and lower scores on the Global Assessment of Functioning Scale than the other two groups. The current study showed a clinical trend in Japanese HD patients similar to previous studies in various countries, suggesting that HD may be a universal disease with consistent clinical symptoms.