Augmentation of learning in schizophrenia by D-serine is related to auditory and frontally-generated biomarkers: A randomized, double-blind, placebo-controlled study

Auditory cognition is impaired in schizophrenia, and typically engages a complex, distributed, hierarchical network, including both auditory and frontal input. We recently demonstrated proof of principle for the target engagement of an N-methyl-D-aspartate-type glutamate receptor (NMDAR) agonist + auditory targeted remediation (d-serine+AudRem) combination, showing significant improvement in auditory-learning induced plasticity and mismatch negativity. In this secondary analysis, we report on frontal EEG outcomes, assessing for both generalized effects and the mechanism of auditory plasticity. 21 schizophrenia or schizoaffective disorder participants were randomized to three 1x weekly AudRem + double-blind d-serine (100 mg/kg) visits. In AudRem, participants indicated which paired tone was higher in pitch. The focus of this secondary analysis was a frontally (premotor) mediated EEG outcome- event-related desynchronization in the b band (b-ERD), which was shown to be sensitive to AudRem in previous studies. d-Serine+AudRem led to significant improvement in b-ERD power across the retention and motor preparation intervals (F 1,18 =6.0, p=0.025) vs. AudRem alone. b-ERD was significantly related to baseline cognition, but not auditory-learning induced plasticity. The principal finding of this prespecified secondary analysis are that in addition to improving auditory based biomarkers, the d-serine+AudRem combination led to significant improvement in biomarkers thought to represent frontally mediated dysfunction, suggesting potential generalization of effects. Changes in auditory-learning induced plasticity were independent of these frontally mediated biomarkers. Ongoing work will assess whether d-serine+AudRem is sufficient to remediate cognition or whether targeting frontal NMDAR deficits with higher-level remediation may also be required. Trial Registration: NCT03711500.

A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Tocilizumab, An Interleukin-6 Receptor Antibody, For Residual Symptoms in Schizophrenia

Evidence from preclinical, epidemiological, and human studies indicates that inflammation, and in particular elevated interleukin-6 (IL-6) activity, may be related to clinical manifestations and pathophysiology of schizophrenia. Furthermore, studies in preclinical models suggest that decreasing IL-6 activity may mitigate or reverse some of these deficits. The purpose of this trial was to test whether an IL-6 receptor antibody, tocilizumab, would improve residual positive and negative symptoms and cognitive deficits in schizophrenia. We randomized 36 clinically stable, moderately symptomatic (i.e., Positive and Negative Syndrome Scale (PANSS) >60) individuals with schizophrenia to 3 monthly infusions of 8 mg/kg tocilizumab or placebo (normal saline). The primary outcome was effect at week 12 on the PANSS Total Score. Effects on the MATRICS, other PANSS subscales, Clinical Global Impression, and Global Assessment of Functioning were secondary outcomes. There were no observed treatment effects on any behavioral outcome measure. Baseline C-reactive protein (CRP) or cytokine levels did not predict treatment outcome, nor were there correlations between changes in these inflammatory markers and the measured outcomes. As expected, IL-6 and IL-8 increased, while CRP decreased, in the tocilizumab group compared with the placebo group. This study did not reveal any evidence that an IL-6 receptor antibody affects behavioral outcomes in schizophrenia. One potential explanation is the lack of capacity of this agent to penetrate the central nervous system. Additional trials of medications aimed at targeting cytokine overactivity that act directly on brain function and/or treatment in early-stage psychosis populations are needed.

Attention bias in adults with anorexia nervosa, obsessive-compulsive disorder, and social anxiety disorder

BACKGROUND

Attention bias to threat (selective attention toward threatening stimuli) has been frequently found in anxiety disorder samples, but its distribution both within and beyond this category is unclear. Attention bias has been studied extensively in social anxiety disorder (SAD) but relatively little in obsessive compulsive disorder (OCD), historically considered an anxiety disorder, or anorexia nervosa (AN), which is often characterized by interpersonal as well as body image/eating fears.

METHODS

Medication-free adults with SAD (n = 43), OCD (n = 50), or AN (n = 30), and healthy control volunteers (HC, n = 74) were evaluated for attention bias with an established dot probe task presenting images of angry and neutral faces. Additional outcomes included attention bias variability (ABV), which summarizes fluctuation in attention between vigilance and avoidance, and has been reported to have superior reliability. We hypothesized that attention bias would be elevated in SAD and associated with SAD severity.

RESULTS

Attention bias in each disorder did not differ from HC, but within the SAD group attention bias correlated significantly with severity of social avoidance. ABV was significantly lower in OCD versus HC, and it correlated positively with severity of OCD symptoms within the OCD group.

CONCLUSIONS

Findings do not support differences from HC in attention bias to threat faces for SAD, OCD, or AN. Within the SAD sample, the association of attention bias with severity of social avoidance is consistent with evidence that attention bias moderates development of social withdrawal. The association of ABV with OCD diagnosis and severity is novel and deserves further study.

A Multicenter, Rater-Blinded, Randomized Controlled Study of Auditory Processing-Focused Cognitive Remediation Combined With Open-Label Lurasidone in Patients With Schizophrenia and Schizoaffective Disorder

OBJECTIVE

Small-scale studies of auditory processing cognitive remediation programs have demonstrated efficacy in schizophrenia. We describe a multicenter, rater-blinded, randomized, controlled study of auditory-focused cognitive remediation, conducted from June 24, 2010, to June 14, 2013, and approved by the local institutional review board at all sites.

METHOD

Prior to randomization, participants with schizophrenia (DSM-IV-TR) were stabilized on a standardized antipsychotic regimen (lurasidone [40-160 mg/d]), followed by randomization to adjunctive cognitive remediation: auditory focused (Brain Fitness) versus control (nonspecific video games), administered 1-2 times weekly for 30 sessions. Coprimary outcome measures included MATRICS Consensus Cognitive Battery (MCCB) and the University of California, San Diego, Performance-Based Skills Assessment-Brief scale.

RESULTS

120 participants were randomized and completed at least 1 auditory-focused cognitive remediation (n = 56) or video game control session (n = 64). 74 participants completed ≥ 25 sessions and postrandomization assessments. At study completion, the change from prestabilization was statistically significant for MCCB composite score (d = 0.42, P < .0001) across groups. Participants randomized to auditory-focused cognitive remediation had a trend-level higher mean MCCB composite score compared to participants randomized to control cognitive remediation (P = .08). After controlling for scores at the time of randomization, there were no significant between-treatment group differences at study completion.

CONCLUSIONS

Auditory processing cognitive remediation combined with lurasidone did not lead to differential improvement over nonspecific video games. Across-group improvement from prestabilization baseline to study completion was observed, but since all participants were receiving lurasidone open label, it is difficult to interpret the source of these effects. Future studies comparing both pharmacologic and behavioral cognitive enhancers should consider a 2 × 2 design, using a control for both the medication and the cognitive remediation.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01173874.

PREPULSE INHIBITION DEFICITS ONLY IN FEMALES WITH OBSESSIVE-COMPULSIVE DISORDER

BACKGROUND

Deficits in sensorimotor gating have been hypothesized to underlie the inability to inhibit repetitive thoughts and behaviors. To test this hypothesis, this study assessed prepulse inhibition (PPI), a measure of sensorimotor gating, across three psychiatric disorders (obsessive-compulsive disorder [OCD], social anxiety disorder [SAD], and anorexia nervosa [AN]) whose clinical presentations include repetitive thoughts and behaviors

METHODS

We tested acoustic PPI in unmedicated individuals with OCD (n = 45), SAD (n = 37), and AN (n = 26), and compared their results to matched healthy volunteers (n = 62). All participants completed a structured clinical interview and a clinical assessment of psychiatric symptom severity.

RESULTS

Percent PPI was significantly diminished in females with OCD compared to healthy female volunteers (P = .039). No other differences between healthy volunteers and participants with disorders (male or female) were observed. Percent PPI was not correlated with severity of obsessions and compulsions, as measured by the Yale-Brown Obsessive Compulsive Scale.

CONCLUSIONS

This is the first study to assess PPI in participants with SAD or AN, and the largest study to assess PPI in participants with OCD. We found PPI deficits only in females with OCD, which suggests that the cortico-striato-pallido-thalamic and pontine circuitry (believed to underlie PPI) differs between males and females with OCD. Given that PPI deficits were only present in females with OCD and not related to repetitive thoughts and behaviors, our results do not support the hypothesis that sensorimotor gating deficits, as measured by PPI, underlie the inability to inhibit repetitive thoughts and behaviors in individuals with OCD, SAD, and AN.

Perceived and Police-Reported Neighborhood Crime: Linkages to Adolescent Activity Behaviors and Weight Status

PURPOSE

Inadequate physical activity and obesity during adolescence are areas of public health concern. Questions exist about the role of neighborhoods in the etiology of these problems. This research addressed the relationships of perceived and objective reports of neighborhood crime to adolescent physical activity, screen media use, and body mass index (BMI).

METHODS

Socioeconomically and racially/ethnically diverse adolescents (N = 2,455, 53.4% female) from 20 urban, public middle and high schools in Minneapolis/St. Paul, Minnesota responded to a classroom survey in the Eating and Activity in Teens 2010 study. BMI was measured by research staff. Participants' mean age was 14.6 (standard deviation = 2.0); 82.7% represented racial/ethnic groups other than non-Hispanic white. Linear regressions examined associations between crime perceived by adolescents and crime reported to police and the outcomes of interest (BMI z-scores, physical activity, and screen time). Models were stratified by gender and adjusted for age, race/ethnicity, socioeconomic status, and school.

RESULTS

BMI was positively associated with perceived crime among girls and boys and with reported crime in girls. For girls, there was an association between higher perceived crime and increased screen time; for boys, between higher reported property crime and reduced physical activity. Perceived crime was associated with reported crime, both property and personal, in both genders.

CONCLUSIONS

Few prior studies of adolescents have studied the association between both perceived and reported crime and BMI. Community-based programs for youth should consider addressing adolescents' safety concerns along with other perceived barriers to physical activity. Interventions targeting actual crime rates are also important.

Changes in the prevalence of mood and anxiety disorders among male and female current smokers in the United States: 1990-2001

PURPOSE

The present study investigated whether the prevalence of mood and anxiety disorders has increased over time among current smokers and whether these trends differ by gender and in comparison with nonsmokers.

METHODS

Data were drawn from the National Comorbidity Survey (1990) and the National Comorbidity Survey-Replication (2001), representative samples of the US adult population. Binomial regression analyses were used to determine differences between mood and anxiety disorders among current smokers in 1990 and 2001 and whether these differed by gender and in comparison with those who were former or never current smokers.

RESULTS

Any anxiety disorder, panic attacks, panic disorder, social anxiety disorder and dysthymia were all significantly more common among current smokers in 2001 compared with 1990 and except for social anxiety disorder these increases were significantly greater than any trend found in non-smokers. Increases in panic attacks, social anxiety disorder, and dysthymia were more pronounced in female than in male smokers. Major depressive disorder and generalized anxiety disorder were not found to increase over time among smokers.

CONCLUSIONS

The prevalence of several anxiety disorders and dysthymia among current smokers appears to have increased from 1990 to 2001. Future studies are needed to determine whether these trends have continued. If so, interventions aimed at moving the prevalence lower may have limited success if treatment of mental health problems such as anxiety disorders and certain mood disorders are not considered in the development and dissemination of tobacco control programs.

Dynamics of Saturn's Magnetosphere from MIMI During Cassini's Orbital Insertion

The Magnetospheric Imaging Instrument (MIMI) onboard the Cassini spacecraft observed the saturnian magnetosphere from January 2004 until Saturn orbit insertion (SOI) on 1 July 2004. The MIMI sensors observed frequent energetic particle activity in interplanetary space for several months before SOI. When the imaging sensor was switched to its energetic neutral atom (ENA) operating mode on 20 February 2004, at approximately 10(3) times Saturn's radius RS (0.43 astronomical units), a weak but persistent signal was observed from the magnetosphere. About 10 days before SOI, the magnetosphere exhibited a day-night asymmetry that varied with an approximately 11-hour periodicity. Once Cassini entered the magnetosphere, in situ measurements showed high concentrations of H+, H2+, O+, OH+, and H2O+ and low concentrations of N+. The radial dependence of ion intensity profiles implies neutral gas densities sufficient to produce high loss rates of trapped ions from the middle and inner magnetosphere. ENA imaging has revealed a radiation belt that resides inward of the D ring and is probably the result of double charge exchange between the main radiation belt and the upper layers of Saturn's exosphere.