Meta-Review of Metanalytic Studies with Repetitive Transcranial Magnetic Stimulation (rTMS) for the Treatment of Major Depression

BACKGROUND: Major Depression (MD) and treatment-resistant depression (TRD) are worldwide leading causes of disability and therapeutic strategies for these impairing and prevalent conditions include pharmacological augmentation strategies and brain stimulation techniques. In this perspective, repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique with a favorable profile of tolerability which, despite being recently approved by the Food and Drug Administration (FDA) for the treatment of patients with medication-refractory unipolar depression, still raises some doubts about most effective parameters of stimulation.METHODS: A literature search was performed using PubMed for the years 2001 through February 2011 in order to review meta-analytic studies assessing efficacy and safety issues for rTMS in depressive disorders. Fifteen meta-analyses were identified and critically discussed in order to provide an updated and comprehensive overview of the topic with specific emphasis on potentially optimal parameters of stimulation.RESULTS: First meta-analyses on the efficacy of rTMS for the treatment of MD and TRD have shown mixed results. On the other hand, more recent meta-analytic studies seem to support the antidepressant efficacy of the technique to a greater extent, also in light of longer periods of stimulation (e.g. > 2 weeks).CONCLUSION: rTMS seems to be an effective and safe brain stimulation technique for the treatment of medication refractory depression. Nevertheless, further studies are needed to better define specific stimulation-related issues, such as duration of treatment as well as durability of effects and predictors of response

Epigenetic modulation of BDNF gene: Differences in DNA methylation between unipolar and bipolar patients

Background The brain derived neurotrophic factor (BDNF) gene and its epigenetic regulation have been repeatedly implicated in the pathophysiology of mood disorders. Following previous investigation in the field, we further investigated differences in BDNF promoter gene methylation in patients with mood disorders, comparing unipolar and bipolar subjects, on the basis of illness phase, gender, age and psychotropic prescription. Methods 154 patients (43 MDD; 61 BD I; 50 BD II), on stable pharmacological treatment, and 44 age-matched, healthy controls were recruited. BDNF methylation levels from peripheral blood mononuclear cells (PBMCs) were compared by analysis of variance followed by Bonferroni's post-hoc test. Results Similar, higher levels of BDNF gene promoter methylation were found in BD II and MDD patients, compared to BD I subjects (P<0.01). When stratified on the basis of mood status, methylation levels of depressed patients were significantly higher, compared to the levels of manic/mixed patients (P<0.01). While gender and age did not seem to influence methylation levels of BDNF gene promoter, patients on lithium and valproate showed overall lower levels. Limitations: Cross-sectional analysis using PBMCs with further investigation with larger samples, including drug-na\uefve patients, needed to replicate findings in neuronal cells. Conclusions Present data confirm our previous results of higher methylation levels in BD II (compared to BD I) and MDD patients (compared to controls). A closer relationship between BD II and MDD, compared to BD I patients as well an association of lower methylation levels with the presence of mania/mixed state, compared to the depressive phase, was observed

Regulation of gene transcription in bipolar disorders: Role of DNA methylation in the relationship between prodynorphin and brain derived neurotrophic factor

Bipolar Disorder (BD) is a prevalent and disabling condition, determined by gene-environment interactions, possibly mediated by epigenetic mechanisms. The present study aimed at investigating the transcriptional regulation of BD selected target genes by DNA methylation in peripheral blood mononuclear cells of patients with a DSM-5 diagnosis of type I (BD-I) and type II (BD-II) Bipolar Disorders (n = 99), as well as of healthy controls (CT, n = 42). The analysis of gene expression revealed prodynorphin (PDYN) mRNA levels significantly reduced in subjects with BD-II but not in those with BD-I, when compared to CT. Other target genes (i.e. catechol-O-methyltransferase (COMT), glutamate decarboxylase (GAD67), serotonin transporter (SERT) mRNA levels remained unaltered. Consistently, an increase in DNA methylation at PDYN gene promoter was observed in BD-II patients vs CT. After stratifying data on the basis of pharmacotherapy, patients on mood-stabilizers (i.e., lithium and anticonvulsants) were found to have lower DNA methylation at PDYN gene promoter. A significantly positive correlation in promoter DNA methylation was observed in all subjects between PDYN and brain derived neurotrophic factor (BDNF), whose methylation status had been previously found altered in BD. Moreover, among key genes relevant for DNA methylation establishment here analysed, an up-regulation of DNA Methyl Transferases 3b (DNMT3b) and of the methyl binding protein MeCP2 (methyl CpG binding protein 2) mRNA levels was also observed again just in BD-II subjects. A clear selective role of DNA methylation involvement in BD-II is shown here, further supporting a role for BDNF and its possible interaction with PDYN. These data might be relevant in the pathophysiology of BD, both in relation to BDNF and for the improvement of available treatments and development of novel ones that modulate epigenetic signatures

Which factors influence onset and latency to treatment in generalized anxiety disorder, panic disorder, and obsessive-compulsive disorder?

Anxiety disorders are common, comorbid, and disabling conditions, often underdiagnosed and under-treated, typically with an early onset, chronic course, and prolonged duration of untreated illness. The present study aimed to explore the influence of sociodemographic and clinical factors in relation to onset and latency to treatment in patients with generalized anxiety disorder (GAD), panic disorder (PD), and obsessive-compulsive disorder (OCD). A total of 157 patients with a Diagnostic and Statistical Manual of Mental Disorders, 4th ed. Text Revision (DSM-IVTR) diagnosis of PD (n=49), GAD (n=68), and OCD (n=40) were recruited, and epidemiological and clinical variables were collected through a specific questionnaire. Statistical analyses were carried out to compare variables across diagnostic groups. PD, GAD, and OCD patients showed a duration of untreated illness of 53.9 ±81.5, 77.47 ±95.76, and 90.6± 112.1 months, respectively. Significant differences between groups were found with respect to age, age of first diagnosis, age of first treatment, family history of psychiatric illness, onset-related stressful events, benzodiazepine prescription as first treatment, antidepressant prescription as first treatment, and helpseeking (self-initiated vs. initiated by others). Patients with GAD, PD, and OCD showed significant differences in factors influencing onset and latency to treatment, which may, in turn, affect condition-related outcome and overall prognosis. Further studies with larger samples are warranted in the field