Davis et al (SEE ARTICLE) performed a meta-analysis of 124 randomized, controlled trials with efficacy data of 10 second-generation vs first-generation antipsychotics. Clozapine, risperidone, olanzapine, and amisulpride were significantly more efficacious than first-generation antipsychotics. They also found no evidence that the dose of first-generation drugs used in comparison with second-generation drugs affects differential efficacy between the two classes.
Aleman et al (SEE ARTICLE) used meta-analytic techniques to integrate the published studies on sex differences in schizophrenia incidence. The mean incidence risk ratio for men to develop schizophrenia relative to women was 1.42 when all studies were included in the analysis (49 effect sizes). The sex difference remained significant when studies that minimized selection biases were analyzed separately. The authors conclude that male sex is a major risk factor for a more severe and therefore more easily recognizable form of schizophrenia.
Hashimoto et al (SEE ARTICLE) report that the serum levels of D-serine and the ratio of D-serine to total (L + D) serine in patients with schizophrenia are significantly decreased in comparison with those of age- and sex-matched normal controls. These findings suggest that, as an endogenous agonist for glycine site on the NMDA receptors, D-serine may play a role in the pathophysiology of schizophrenia, supporting the NMDA receptor hypofunction hypothesis of schizophrenia.
Malaspina and Coleman (SEE ARTICLE) examined the association between smell identification ability and social function in schizophrenia. They demonstrated a robust relationship between smell identification and social drive, which fully explained the observed association of impaired smell identification with both negative symptoms and the deficit syndrome. Almost 50% of the variance in smell identification ability was explained by its similarly strong and independent relationships with social drive and intelligence.
Ho et al (SEE ARTICLE) examined 73 recent-onset schizophrenia patients and 23 healthy volunteers at intake and after an average of 3 years using magnetic resonance imaging. Patients diverged from the normal age-expected trajectory by showing progressive frontal white matter volume reduction, with reciprocal enlargements in frontal and sulcal cerebrospinal fluid volumes. These findings support the growing evidence that there are ongoing brain changes during the course of schizophrenia, and that such changes have functional significance.
In an investigation of state- and trait-related impairments in the function of prefrontal cortices in bipolar disorder, Blumberg et al (SEE ARTICLE) used functional magnetic resonance imaging to measure regional brain activation while subjects performed an event-related color-word Stroop task. Hemisphere-specific disturbances in activation that depended on the polarity of the mood state were detected within the ventrocaudal prefrontal cortex. In addition, blunted activation that was independent of mood state was observed in the left rostroventral prefrontal cortex.
Szanto et al (SEE ARTICLE) found that 77% of 395 older patients with major depression reported feelings that life is empty, thoughts of death, or suicidal ideation at the time of initiation of protocolized pharmacologic treatment. After 12 weeks of treatment, 10% felt that life is empty and 8% reported thoughts of death, but suicidal ideation had resolved in all patients. However, those who were suicidal at baseline had a lower rate of treatment response and needed a longer time to respond.
While folate deficiency has been associated with depression in several clinical studies, other elements of 1-carbon metabolism have been less studied. Bjelland et al (SEE ARTICLE) examined such factors in relation to anxiety disorder and depression in a large Norwegian population-based study. The strongest relationship was observed between the TT genotype of the methylenetetrahydrofolate reductase polymorphism and depression. Total plasma homocysteine level was positively associated with depression, while no relation was found with plasma folate or vitamin B12 levels. None of the factors were related to anxiety disorder.
Frasure-Smith and Lespérance (SEE ARTICLE) examined the importance of depression symptoms and multiple indices of anxiety, anger, and social support in predicting 5-year cardiac mortality in a large post–myocardial infarction sample. Only depression symptoms remained significant after adjustment for cardiac disease severity. Exploratory factor analysis revealed 3 common factors: negative affectivity, overt anger, and social support. Both negative affectivity and some unique aspect of depression predicted cardiac mortality independently of each other and covariates.
Minsky et al (SEE ARTICLE) examined whether previous findings of disproportionate rates of schizophrenia among African Americans are replicated in a large clinical sample and whether similar patterns exist for Latinos. Results indicated that Latinos were more likely to receive a clinical diagnosis of major depression, whereas African Americans were more likely to receive a diagnosis within the schizophrenia spectrum, despite elevated scores of self-reported psychotic symptoms in Latino patients, and, conversely, relatively lower levels of self-reported psychosis and symptom severity in African Americans.
