Mediators of Interpersonal Psychotherapy for Depressed Adolescents On Outcomes in Latinos: The Role of Peer and Family Interpersonal Functioning

Peer and family interpersonal functioning were examined as mediators of the impact of Interpersonal Psychotherapy for Depressed Adolescents (IPT-A; Mufson, Dorta, Moreau, & Weissman, 2004) on depression and suicidal ideation among Latino youth. Only youth self-identifying as Latino (n = 50) were included in the analyses. The majority were female (86%) with a mean age of 14.58 (SD = 1.91). The current sample was drawn from the intent to treat sample of a clinical trial examining the effectiveness of IPT-A as compared with treatment as usual (TAU; Mufson, Dorta, Wickramaratne et al., 2004). Youth were randomly assigned to receive IPT-A or TAU delivered by school-based mental health clinicians. Assessments, completed at baseline and at Weeks 4, 8, and 12 (or at early termination), included self-report measures of depression and interpersonal functioning as well as clinician-Administered measures of depression. Multilevel modeling indicated that IPT-A led to greater improvement in interpersonal functioning with family and peers. Improved family and peer interpersonal functioning emerged as significant partial mediators of the relationship between IPT-A and depression. Only improved family interpersonal functioning emerged as a significant partial mediator of the relationship between IPT-A and suicidal ideation. However, this indirect effect was small, suggesting that most of the benefit of IPT-A for suicidal ideation appears to proceed through a pathway other than family interpersonal functioning. These results suggest that the impact of IPT-A on depressive symptoms is partially mediated by family and peer interpersonal functioning and contributes to our understanding of the mechanisms of IPT-A

Structural neural markers of response to cognitive behavioral therapy in pediatric obsessive-compulsive disorder

Background Cognitive behavioral therapy (CBT) is an effective, first-line treatment for pediatric obsessive-compulsive disorder (OCD). While neural predictors of treatment outcomes have been identified in adults with OCD, robust predictors are lacking for pediatric patients. Herein, we sought to identify brain structural markers of CBT response in youth with OCD. Methods Twenty-eight children/adolescents with OCD and 27 matched healthy participants (7- to 18-year-olds, M = 11.71 years, SD = 3.29) completed high-resolution structural and diffusion MRI (all unmedicated at time of scanning). Patients with OCD then completed 12-16 sessions of CBT. Subcortical volume and cortical thickness were estimated using FreeSurfer. Structural connectivity (streamline counts) was estimated using MRtrix. Results Thinner cortex in nine frontoparietal regions significantly predicted improvement in Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) scores (all ts > 3.4, FDR-corrected ps < .05). These included middle and superior frontal, angular, lingual, precentral, superior temporal, and supramarginal gyri (SMG). Vertex-wise analyses confirmed a significant left SMG cluster, showing large effect size (Cohen's d = 1.42) with 72.22% specificity and 90.00% sensitivity in predicting CBT response. Ten structural connections between cingulo-opercular regions exhibited fewer streamline counts in OCD (all ts > 3.12, Cohen's ds > 0.92) compared with healthy participants. These connections predicted post-treatment CY-BOCS scores, beyond pretreatment severity and demographics, though not above and beyond cortical thickness. Conclusions The current study identified group differences in structural connectivity (reduced among cingulo-opercular regions) and cortical thickness predictors of CBT response (thinner frontoparietal cortices) in unmedicated children/adolescents with OCD. These data suggest, for the first time, that cortical and white matter features of task control circuits may be useful in identifying which pediatric patients respond best to individual CBT.Y