Glutamate in Pediatric Obsessive-Compulsive Disorder and Response to Cognitive-Behavioral Therapy: Randomized Clinical Trial.

Cognitive-behavioral therapy (CBT) is effective for pediatric obsessive-compulsive disorder (OCD), but non-response is common. Brain glutamate (Glu) signaling may contribute to OCD pathophysiology and moderate CBT outcomes. We assessed whether Glu measured with magnetic resonance spectroscopy (MRS) was associated with OCD and/or CBT response. Youths aged 7-17 years with DSM-IV OCD and typically developing controls underwent 3 T proton echo-planar spectroscopic imaging (PEPSI) MRS scans of pregenual anterior cingulate cortex (pACC) and ventral posterior cingulate cortex (vPCC)-regions possibly affected by OCD-at baseline. Controls returned for re-scan after 8 weeks. OCD youth-in a randomized rater-blinded trial-were re-scanned after 12-14 weeks of CBT or after 8 weeks of minimal-contact waitlist; waitlist participants underwent a third scan after crossover to 12-14 weeks of CBT. Forty-nine children with OCD (mean age 12.2±2.9 years) and 29 controls (13.2±2.2 years) provided at least one MRS scan. At baseline, Glu did not differ significantly between OCD and controls in pACC or vPCC. Within controls, Glu was stable from scan-to-scan. Within OCD subjects, a treatment-by-scan interaction (p=0.034) was observed, driven by pACC Glu dropping 19.5% from scan-to-scan for patients randomized to CBT, with minor increases (3.8%) for waitlist participants. The combined OCD participants (CBT-only plus waitlist-CBT) also showed a 16.2% (p=0.004) post-CBT decrease in pACC Glu. In the combined OCD group, within vPCC, lower pre-CBT Glu predicted greater post-CBT improvement in symptoms (CY-BOCS; r=0.81, p=0.00025). Glu may be involved in the pathophysiology of OCD and may moderate response to CBT.

Predicting Anxiety Diagnoses and Severity with the CBCL-A: Improvement Relative to Other CBCL Scales?

The Child Behavior Checklist (CBCL) is a widely used parent-report of child and adolescent behavior. We examined the ability of the CBCL-A scale, a previously published subset of CBCL items, to predict the presence of generalized anxiety disorder (GAD), separation anxiety disorder (SAD), and social phobia (SoP), as well as anxiety severity, among 488 youth randomized in the Child Anxiety Multimodal Study (CAMS). We predicted that the CBCL-A's unique inclusion of items related to somatic symptoms would better identify anxiety disorder and severity than other CBCL scales, given that somatic complaints are often key features of anxiety among youth. Results support the use of the anxiety-based CBCL subscales as first-line screeners for generally elevated symptoms of anxiety, rather than tools to identify specific anxiety disorders. Although somatic symptoms are often reported and included in diagnostic criteria for certain anxiety disorders (e.g., SAD, GAD), the unique combination of somatic and non-somatic symptoms for the CBCL-A subscale did not increase its ability to consistently predict the presence of specific anxiety disorders.

Searching for moderators and mediators of pharmacological treatment effects in children and adolescents with anxiety disorders.

OBJECTIVE: To examine whether age, gender, ethnicity, type of anxiety disorder, severity of illness, comorbidity, intellectual level, family income, or parental education may function as moderators and whether treatment adherence, medication dose, adverse events, or blinded rater's guess of treatment assignment may function as mediators of pharmacological treatment effect in children and adolescents with anxiety disorders. METHOD: The database of a recently reported double-blind placebo-controlled trial of fluvoxamine in 128 youths was analyzed. With a mixed-model random-effects regression analysis of the Pediatric Anxiety Rating Scale total score, moderators and mediators were searched by testing for a three-way interaction (strata by treatment by time). A two-way interaction (strata by time) identified predictors of treatment outcome. RESULTS: No significant moderators of efficacy were identified, except for lower baseline depression scores, based on parent's (but not child's) report, being associated with greater improvement (p < .001). Patients with social phobia (p < .05) and greater severity of illness (p < .001) were less likely to improve, independently of treatment assignment. Blinded rater's guess of treatment assignment acted as a possible mediator (p < .001), but improvement was attributed to fluvoxamine, regardless of actual treatment assignment. Treatment adherence tended to be associated (p = .05) with improvement. CONCLUSIONS: In this exploratory study, patient demographics, illness characteristics, family income, and parental education did not function as moderators of treatment effect. Social phobia and severity of illness predicted less favorable outcome. Attribution analyses indicated that study blindness remained intact. The presence of concomitant depressive symptoms deserves attention in future treatment studies of anxious children.

MRSI correlates of cognitive-behavioral therapy in pediatric obsessive-compulsive disorder.

BACKGROUND: The brain mechanisms of cognitive-behavioral therapy (CBT), a highly effective treatment for pediatric obsessive-compulsive disorder (OCD), are unknown. Neuroimaging in adult OCD indicates that CBT is associated with metabolic changes in striatum, thalamus, and anterior cingulate cortex. We therefore probed putative metabolic effects of CBT on these brain structures in pediatric OCD using proton magnetic resonance spectroscopic imaging (1H MRSI). METHOD: Five unmedicated OCD patients (4 ♀, 13.5±2.8) and 9 healthy controls (7 ♀, 13.0±2.5) underwent MRSI (1.5 T, repetition-time/echo-time=1500/30 ms) of bilateral putamen, thalamus and pregenual anterior cingulate cortex (pACC). Patients were rescanned after 12 weeks of exposure-based CBT. The Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) of OCD symptoms was administered before and after CBT. RESULTS: Four of 5 patients responded to CBT (mean 32.8% CY-BOCS reduction). Multiple metabolite effects emerged. Pre-CBT, N-acetyl-aspartate+N-acetyl-aspartyl-glutamate (tNAA) in left pregenual anterior cingulate cortex (pACC) was 55.5% higher in patients than controls. Post-CBT, tNAA (15.0%) and Cr (23.9%) in left pACC decreased and choline compounds (Cho) in right thalamus increased (10.6%) in all 5 patients. In left thalamus, lower pre-CBT tNAA, glutamate+glutamine (Glx), and myo-inositol (mI) predicted greater post-CBT drop in CY-BOCS (r=0.98) and CY-BOCS decrease correlated with increased Cho. CONCLUSIONS: Interpretations are offered in terms of the Glutamatergic Hypothesis of Pediatric OCD. Similar to 18FDG-PET in adults, objectively measurable regional MRSI metabolites may indicate pediatric OCD and predict its response to CBT.

Remission after acute treatment in children and adolescents with anxiety disorders: findings from the CAMS.

OBJECTIVE: To report on remission rates in anxious youth who participated in the Child/Adolescent Anxiety Multimodal Study (CAMS). The CAMS, a multisite clinical trial, randomized 488 children and adolescents (ages 7-17 years; 79% Caucasian; 50% female) with separation, social, and/or generalized anxiety disorder to a 12-week treatment of sertraline (SRT), cognitive behavioral therapy (CBT), their combination (COMB), or clinical management with pill placebo (PBO). METHOD: The primary definition of remission was loss of all study-entry anxiety disorder diagnoses; additional definitions of remission were used. All outcomes were rated by independent evaluators blind to treatment assignment. Predictors of remission were also examined. RESULTS: Remission rates after 12 weeks of treatment ranged from 46% to 68% for COMB, 34% to 46% for SRT, 20% to 46% for CBT, and 15% to 27% for PBO. Rates of remission (i.e., achieving a nearly symptom-free state) were significantly lower than rates of response (i.e., achieving a clinically meaningful improvement relative to baseline) for the entire sample. Youth who received COMB had significantly higher rates of remission compared to all other treatment groups. Both monotherapies had higher remission rates compared to PBO, but rates were not different from each other. Predictors of remission were younger age, nonminority status, lower baseline anxiety severity, absence of other internalizing disorders (e.g., anxiety, depression), and absence of social phobia. CONCLUSIONS: For the majority of children, some symptoms of anxiety persisted, even among those showing improvement after 12 weeks of treatment, suggesting a need to augment or extend current treatments for some children.

Clinical characteristics of anxiety disordered youth.

Reports the characteristics of a large, representative sample of treatment-seeking anxious youth (N=488). Participants, aged 7-17 years (mean 10.7 years), had a principal DSM-IV diagnosis of separation anxiety disorder (SAD), generalized anxiety disorder (GAD), or social phobia (SP). Although youth with a co-primary diagnosis for which a different disorder-specific treatment would be indicated (e.g., major depressive disorder, substance abuse) were not included, there were few other exclusion criteria. Participants and their parent/guardian underwent an extensive baseline assessment using a broad array of measures capturing diagnostic status, anxiety symptoms and severity, and areas of functional impairment. Means and standard deviations of the measures of psychopathology and data on diagnostic status are provided. The sample had moderate to severe anxiety disorder and was highly comorbid, with 55.3% of participants meeting criteria for at least one non-targeted DSM-IV disorder. Anxiety disorders in youth often do not present as a single/focused disorder: such disorders in youth overlap in symptoms and are highly comorbid among themselves.