In an 8-week double-blind randomized comparison of olanzapine and clozapine in 25 adolescents with childhood-onset schizophrenia, Shaw et alArticle showed a more consistent pattern of clinical improvement with clozapine, with a significant difference found in alleviation of negative symptoms. The more favorable clinical profile of clozapine was balanced against more overall adverse events.
Ho et alArticle found that the Met allele of a brain-derived neurotrophic factor, possibly through the factor's role in modulating synaptic plasticity, causes a specific cognitive dysfunction in schizophrenia. Unlike healthy volunteers, Met allele–carrier patients had greater visuospatial impairment and small gray matter brain volumes in both ventral and dorsal visual pathways than their Val-homozygous counterparts.
Cannon et alArticle detected an abnormality in the central cholinergic system during depression in subjects with bipolar disorder but not major depressive disorder. Muscarinic type 2 receptor binding by the agonist radioligand [18F]FP-TZTP, which is sensitive to endogenous acetylcholine levels, was reduced during depression in subjects with bipolar disorder, and binding correlated negatively with the severity of depressive symptoms.
Segal et alArticle used sad mood provocation to study the vulnerability of remitted depressed patients for illness relapse. The (re)activation of depressive thinking styles triggered by induced dysphoric states was a significant predictor of relapse over the subsequent 18 months, regardless of whether remission was achieved through antidepressant medication or cognitive behavior therapy.
Linehan et alArticle tested whether treatment effects on patients with borderline personality disorder can be attributed to dialectical behavior therapy (DBT) per se rather than to nonspecific factors of expert therapy. Comparing DBT with expert treatment in the community, they found that DBT appears uniquely effective in reducing suicide attempts.
Arnold et alArticle analyzed the gene SLC1A1 in 157 individuals with obsessive-compulsive disorder (OCD) and their relatives. SLC1A1 is located within the strongest linkage peak (9p24) identified in the only published genome scan of OCD to the authors' knowledge. In the current study, a significant association was found between variants of SLC1A1 and OCD, particularly in males, suggesting that SLC1A1 variants may confer susceptibility to OCD through their influence on glutamatergic neurotransmission.
The neuronal and epithelial glutamate transporter gene (SLC1A1/EAAC1) on chromosome 9p24 is a positional and functional candidate gene in obsessive-compulsive disorder (OCD). Dickel et alArticle tested for association at 9 polymorphisms spanning SLC1A1/EAAC1. One polymorphism and the adjacent haplotype block showed evidence of association with early-onset OCD in males but not females. These findings support both gene × sex interaction and the involvement of the glutamate system in OCD.
Friedman et alArticle evaluated the presence of gray matter cellular alterations early in the course of autism. A group of young children with autism spectrum disorder were compared with children having delayed development and typical development using magnetic resonance spectroscopy and regression analyses. Results revealed a pattern of gray matter abnormalities distinct to autism spectrum disorder, suggesting decreased cellularity, or density, at this early point.
Plessen et alArticle compared anatomical magnetic resonance brain images from 51 children and adolescents with ADHD and 63 healthy controls aged 6 to 18 years. Overall hippocampal volumes were enlarged in subjects with ADHD. By using novel surface-based analyses, changes could further be localized to the head of the hippocampus. Moreover, they found disturbances in connectivity between the amygdala and orbitofrontal cortex, which they speculate may contribute to the impaired self-regulatory control observed in children with ADHD.
Studies of human cigarette smokers reveal considerable interindividual variability in the extent of smoking-induced dopamine release. Brody et alArticle determined associations between common gene variants of the brain dopamine reward pathway and smoking-induced dopamine release. Smokers with genes associated with low resting dopamine tone had more smoking-induced dopamine release than those with the alternate genotypes.
Hahn et alArticle examined the differences in craving, alcohol consumption, and alcohol outcome expectancies between ALDH2*1/*2 and ALDH2*1/*1 alcoholics and found that the psychological expectancies of drinking are more positive and less negative for ALDH2*1/*2 alcoholics, whose blood acetaldehyde levels are higher after drinking than alcoholics with ALDH2*/*1. A role of acetaldehyde is implied in these effects, which seem to override the usual discomfort effects associated with protection against alcohol drinking.
Simon et alArticle examined the association between obesity and a range of mood, anxiety, and substance use disorders in the US adult population. Mood and anxiety disorders were associated with 20% to 50% higher odds of obesity, while substance use disorders were associated with 20% lower risk. The association between mood disorders and obesity varied by educational level and race, suggesting that social or cultural factors may play a role in this relationship.
This Month in Archives of General Psychiatry. Arch Gen Psychiatry. 2006;63(7):714. doi:10.1001/archpsyc.63.7.714