Data on the impact of SSRIs and depression symptoms on the neural activities in obsessive-compulsive disorder at rest

Development and validation of a machine learning model to predict cognitive behavioral therapy outcome in obsessive-compulsive disorder using clinical and neuroimaging data

Cognitive behavioral therapy (CBT) is a first-line treatment for obsessive-compulsive disorder (OCD), but clinical response is difficult to predict. In this study, we aimed to develop predictive models using clinical and neuroimaging data from the multicenter Enhancing Neuro-Imaging and Genetics through Meta-Analysis (ENIGMA)-OCD consortium. Baseline clinical and resting-state functional magnetic imaging (rs-fMRI) data from 159 adult patients aged 18-60 years (88 female) with OCD who received CBT at four treatment/neuroimaging sites were included. Fractional amplitude of low frequency fluctuations, regional homogeneity and atlas-based functional connectivity were computed. Clinical CBT response and remission were predicted using support vector machine and random forest classifiers on clinical data only, rs-fMRI data only, and the combination of both clinical and rs-fMRI data. The use of only clinical data yielded an area under the ROC curve (AUC) of 0.69 for predicting remission (p=0.001). Lower baseline symptom severity, younger age, an absence of cleaning obsessions, unmedicated status, and higher education had the highest model impact in predicting remission. The best predictive performance using only rs-fMRI was obtained with regional homogeneity for remission (AUC=0.59). Predicting response with rs-fMRI generally did not exceed chance level. Machine learning models based on clinical data may thus hold promise in predicting remission after CBT for OCD, but the predictive power of multicenter rs-fMRI data is limited.

Abnormalities of Localized Connectivity in Obsessive-Compulsive Disorder: A Voxel-Wise Meta-Analysis

Background: A large amount of resting-state functional magnetic resonance imaging (rs-fMRI) studies have revealed abnormalities of regional homogeneity (ReHo, an index of localized intraregional connectivity) in the obsessive-compulsive disorder (OCD) in the past few decades, However, the findings of these ReHo studies have remained inconsistent. Hence, we performed a meta-analysis to investigate the concurrence across ReHo studies for clarifying the most consistent localized connectivity underpinning this disorder. Methods: A systematic review of online databases was conducted for whole-brain rs-fMRI studies comparing ReHo between OCD patients and healthy control subjects (HCS). Anisotropic effect size version of the seed-based d mapping, a voxel-wise meta-analytic approach, was adopted to explore regions of abnormal ReHo alterations in OCD patients relative to HCS. Additionally, meta-regression analyses were conducted to explore the potential effects of clinical features on the reported ReHo abnormalities. Results: Ten datasets comprising 359 OCD patients and 361 HCS were included. Compared with HCS, patients with OCD showed higher ReHo in the bilateral inferior frontal gyri and orbitofrontal cortex (OFC). Meanwhile, lower ReHo was identified in the supplementary motor area (SMA) and bilateral cerebellum in OCD patients. Meta-regression analysis demonstrated that the ReHo in the OFC was negatively correlated with illness duration in OCD patients. Conclusions: Our meta-analysis gave a quantitative overview of ReHo findings in OCD and demonstrated that the most consistent localized connectivity abnormalities in individuals with OCD are in the prefrontal cortex. Meanwhile, our findings provided evidence that the hypo-activation of SMA and cerebellum might be associated with the pathophysiology of OCD.

Alterations in resting-state local functional connectivity in obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) is increasingly conceptualized as a brain connectivity disorder. Recently, abnormalities in remote resting-state functional connectivity (FC) have been well demonstrated in the frontoparietal areas that linked impairments in large-scale intrinsic brain networks with aberrant fronto-striatal interactions. Beyond the remote FC abnormalities in OCD, many studies using regional homogeneity (ReHo) analysis have reported local FC alterations. However, their results were not entirely consistent.

METHODS

We conducted a voxel-wise meta-analysis of ReHo studies to identify consistent local FC abnormalities in patients with OCD. A seed-based d mapping approach was used.

RESULTS

Eight studies that compared 200 patients with OCD and 187 healthy controls were included. Increased ReHo in the lateral orbitofrontal cortices and dorsomedial prefrontal cortices bilaterally, and decreased ReHo in the fusiform gyri bilaterally were the most consistent and reliable findings in patients with OCD relative to healthy controls.

LIMITATIONS

The number of available studies included in the meta-analysis was relatively small. Many potential confounds on changes in ReHo warrant further attention.

CONCLUSIONS

These regions are critically implicated in the pathophysiology of OCD. Our findings in local FC alterations are complementary to the abnormalities in remote FC in OCD, contributing to the modeling of brain functional connectomes in OCD.