Beyond the treatment of epilepsy: new applications of vagus nerve stimulation in psychiatry.
ABSTRACT Vagus nerve stimulation (VNS) in humans generally refers to stimulation of the left vagus nerve at the cervical level VNS is an established treatment largely devoid of severe side effect for medically refractory partial onset seizures and has been used in more than 16,000 patients. Over the past 5 years, applications in other neuropsychiatric disorders have been investigated with a special emphasis on depression. Recent data from an open-label, multi-center pilot study involving 60 patients suggest a potential clinical usefulness in the acute and maintenance treatment of drug-resistant depressive disorder. The perspective of VNS as along-term treatment with the advantage of assured compliance makes it an interesting technique to potentially treat drug-resistant depression. However, definite therapeutic effects of clinical significance remain to be confirmed in large placebo-controlled trial. Results of clinical pilot studies involving patients suffering from obesity and Alzheimer's disease indicate that VNS might induce weight loss and improve cognition. Besides its clinical usefulness, VNS can be used as a research tool, allowing neurophysiologic investigations of the parasympathetic system and its interactions with other parts of the central nervous system.
- SourceAvailable from: Thomas E Schlaepfer[Show abstract] [Hide abstract]
ABSTRACT: Most patients suffering from psychiatric disorders respond to combinations of psycho- and psychopharmacotherapy; however there are patients who profit little if anything even after many years of treatment. Since about a decade different modalities of targeted neuromodulation - among them most prominently - deep brain stimulation (DBS) - are being actively researched as putative approaches to very treatment-resistant forms of those disorders. Recently, promising pilot data have been reported both for major depression (MD) and obsessive-compulsive disorder (OCD). Given the fact that patients included in DBS studies had been treated unsuccessfully for many years with conventional treatment methods, renders these findings remarkable. Remarkable is the fact, that in case of the long-term studies underway for MD, patients show a stable response. This gives hope to a substantial percentage of therapy-resistant psychiatric patients requiring new therapy approaches. There are no fundamental ethic objections to its use in psychiatric disorders, but until substantial clinical data is available, mandatory standards are needed. DBS is a unique and very promising method for the treatment of therapy-resistant psychiatric patients. The method allows manipulating pathological neuronal networks in a very precise way.Frontiers in Integrative Neuroscience 01/2011; 5:29.
- The World Journal of Biological Psychiatry 02/2010; 11(1):2-18. · 3.57 Impact Factor
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ABSTRACT: Human brown adipose tissue (BAT) activity is inversely related to obesity and positively related to energy expenditure. BAT is highly innervated and it is suggested the vagus nerve mediates peripheral signals to the central nervous system, there connecting to sympathetic nerves that innervate BAT. Vagus nerve stimulation (VNS) is used for refractory epilepsy, but is also reported to generate weight loss. We hypothesize VNS increases energy expenditure by activating BAT. FIFTEEN PATIENTS WITH STABLE VNS THERAPY (AGE: 45±10yrs; body mass index; 25.2±3.5 kg/m(2)) were included between January 2011 and June 2012. Ten subjects were measured twice, once with active and once with inactivated VNS. Five other subjects were measured twice, once with active VNS at room temperature and once with active VNS under cold exposure in order to determine maximal cold-induced BAT activity. BAT activity was assessed by 18-Fluoro-Deoxy-Glucose-Positron-Emission-Tomography-and-Computed-Tomography. Basal metabolic rate (BMR) was significantly higher when VNS was turned on (mean change; +2.2%). Mean BAT activity was not significantly different between active VNS and inactive VNS (BAT SUV(Mean); 0.55±0.25 versus 0.67±0.46, P = 0.619). However, the change in energy expenditure upon VNS intervention (On-Off) was significantly correlated to the change in BAT activity (r = 0.935, P<0.001). VNS significantly increases energy expenditure. The observed change in energy expenditure was significantly related to the change in BAT activity. This suggests a role for BAT in the VNS increase in energy expenditure. Chronic VNS may have a beneficial effect on the human energy balance that has potential application for weight management therapy. The study was registered in the Clinical Trial Register under the ClinicalTrials.gov Identifier NCT01491282.PLoS ONE 01/2013; 8(10):e77221. · 3.53 Impact Factor