Decreased brain-derived neurotrophic factor plasma levels in psoriasis patients

Brain-derived neurotrophic factor (BDNF) is associated with neuroplasticity and synaptic strength, and is decreased in conditions associated with chronic stress. Nevertheless, BDNF has not yet been investigated in psoriasis, a chronic inflammatory systemic disease that is exacerbated by stress. Therefore, our aim was to determine BDNF plasma levels in psoriasis patients and healthy controls. Adult patients (n=94) presenting with psoriasis for at least 1 year were enrolled, and age- and gender-matched with healthy controls (n=307) from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Participants had neither a previous history of coronary artery disease nor current episode of major depression. BDNF plasma levels were determined using the Promega ELISA kit. A general linear model was used to compare BDNF levels in psoriasis patients and controls, with age, gender, systolic blood pressure, serum fasting glucose, blood lipid levels, triglycerides, smoking status, and body mass index examined. After adjusting for clinical and demographic variables, significantly decreased BNDF plasma levels were observed in psoriasis patients (P=0.01) (estimated marginal means of 3922 pg/mL; 95%CI=2660-5135) compared with controls (5788 pg/mL; 95%CI=5185-6442). Similar BDNF levels were found in both mild and severe cases of psoriasis. Our finding, that BDNF is decreased in psoriasis, supports the concept of a brain-skin connection in psoriasis. Further studies should determine if BDNF is increased after specific psoriasis treatments, and associated with different disease stages.     

Transcranial direct current stimulation in psychiatric disorders

The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry.     

Impact of escitalopram on vagally mediated cardiovascular function in healthy participants: implications for understanding differential age-related,treatment emergent effects

Rationale

Black box warnings for young adults under the age of 25 years indicate that antidepressants may increase risk of suicide. While underlying mechanisms for age-related treatment effects remain unclear, vagally mediated cardiovascular function may play a key role. Decreased heart rate (HR) and an increase in its variability (HRV) improve one’s capacity to adapt to environmental stress and attenuate risk for suicide.

Objectives

Using a double blind, randomized, placebo-controlled, crossover, experimental study, we examine whether a single dose of escitalopram (20 mg) attenuates cardiovascular responses to stress under experimental conditions and determine whether age moderates these effects.

Methods

Forty-four healthy females received a single dose of escitalopram (20 mg) and placebo treatment separated by a 1-week interval (>5 half-lives). HR and high frequency HRV (HF HRV normalized units; 0.15–0.40 Hz) were measured during resting state and stress.

Results

While escitalopram attenuated the increase in HR and increased HF HRV, these moderate to large effects were only significant in participants over 25 years of age. No beneficial cardiovascular effects of escitalopram were observed in those under the age of 25.

Conclusions

Maturational differences in the development of the prefrontal cortex—a critical region in the central network of autonomic control—may underpin these differential findings. This study provides a theoretical framework on which future research on treatment-emergent suicidality in clinical populations could be based.     

Transcranial direct current stimulation and repetitive transcranial magnetic stimulation in consultation-liaison psychiatry

Patients with clinical diseases often present psychiatric conditions whose pharmacological treatment is hampered due to hazardous interactions with the clinical treatment and/or disease. This is particularly relevant for major depressive disorder, the most common psychiatric disorder in the general hospital. In this context, nonpharmacological interventions could be useful therapies; and, among those, noninvasive brain stimulation (NIBS) might be an interesting option. The main methods of NIBS are repetitive transcranial magnetic stimulation (rTMS), which was recently approved as a nonresearch treatment for some psychiatric conditions, and transcranial direct current stimulation (tDCS), a technique that is currently limited to research scenarios but has shown promising results. Therefore, our aim was to review the main medical conditions associated with high depression rates, the main obstacles for depression treatment, and whether these therapies could be a useful intervention for such conditions. We found that depression is an important and prevalent comorbidity in a variety of diseases such as epilepsy, stroke, Parkinson''s disease, myocardial infarction, cancer, and in other conditions such as pregnancy and in patients without enteral access. We found that treatment of depression is often suboptimal within the above contexts and that rTMS and tDCS therapies have been insufficiently appraised. We discuss whether rTMS and tDCS could have a significant impact in treating depression that develops within a clinical context, considering its unique characteristics such as the absence of pharmacological interactions, the use of a nonenteral route, and as an augmentation therapy for antidepressants.