Dear colleagues,
I am delighted to introduce our third issue of 2014 featuring latest articles in the areas of biological markers and treatment strategies in schizophrenia and psychotic disorders.
In their review, Zakharyan and Boyajyan demonstrated the presence of both genetically and environmentally determined alterations in mRNA and protein expressions of several proinflammatory and chemotactic cytokines in schizophrenia (SCZ) patients. They draw conclusions on using these cytokines and their receptors as additional therapeutic targets for treatment.
Using structural magnetic resonance imaging (sMRI) and proton magnetic resonance spectroscopy (1H MRS), Hasan and colleagues investigated the relationship between hippocampal anomalies and their functional relevance in patients with first-episode SCZ. Smaller volumes of the left hippocampus were found to be associated with lower verbal memory performances. Moreover, an inverse correlation between neurochemical ratios and verbal memory was detected, whereas cognitive flexibility and working memory scores were not correlated with MRI and 1H MRS values.
Schulze and colleagues tested the performance of polygenic models in discriminating between psychiatric disorders and healthy controls, and among cases with distinct psychiatric disorders. Genome-wide association studies (GWAS) were used to assign weights to individual alleles, based on odds ratios, which were then used to calculate allele scores for individual cases and controls, summing across many single nucleotide polymorphisms (SNPs). The most informative SNPs were overlapping in bipolar disorder, major depressive disorder and SCZ, whereas little or no overlap was seen for allele scores for psychiatric disorders and those for Parkinson's disease.
The relative specificity of deficits in olfactory processing in SCZ patients and non-ill first-degree relatives as well as in youth at clinical or genetic risk for developing SCZ were investigated by Kamath and colleagues. Results showed that both patients and first-degree relatives were impaired in odour identification, but deficits in odour discrimination were limited to the patient group. Youth at genetic risk were impaired in odour identification, whereas youth at clinical risk showed deficits in both tasks. The role of an isolated odour identification impairment as genetic marker for SCZ is discussed.
In a signed differential mapping (SDM) meta-analysis using voxel-based morphometry (VBM) studies, Fusar-Poli and colleagues scrutinized neuroanatomical markers of genetic liability to psychosis. Grey matter reductions in the anterior cingulate were considered markers of genetic liability to psychosis while reductions in the temporal gyrus and cerebellum were discussed as markers of a first onset of the illness.
Introducing our second topic, Cordes and colleagues set out to examine whether a preventive weight management program reduces weight gain during olanzapine treatment and whether there is an effect on metabolic parameters in patients with SCZ or schizoaffective disorder. Although patients who took part in the program showed a similar increase in weight, they had a smaller increase in waist circumference as well as a smaller increase in fasting glucose and 2-h glucose after oral glucose load than controls.
Kranaster and colleagues retrospectively investigated the clinical outcome and safety in patients with SCZ treated with electroconvulsive therapy (ECT) and receiving ketamine anaesthesia and compared seizure parameters compared to ECT-treated SCZ patients with thiopental anaesthesia. All but one patient receiving ECT with ketamine responded or remitted; moreover, ECT with ketamine was associated with longer seizures.
Finally, Chowdhury and colleagues examined the potential role of several SNPs, which have known regulatory functions in weight control and energy homeostasis, in weight gain induced by second-generation antipsychotic medications in SCZ patients. The authors found none of the analysed SNPs in the cocaine amphetamine and regulated transcript (CART), polypeptide pro-opiomelancortin (POMC) and the agouti related protein (AGRP) to be associated with antipsychotic induced weight gain.
Yours sincerely,
Siegfried Kasper, MD
Chief Editor