title: Effectiveness and safety of vagus nerve stimulation for severe treatment-resistant major depression in clinical practice after FDA approval: outcomes at 1 year.
abstract: OBJECTIVE
  To describe the outcomes of a consecutive series of depressed patients treated with vagus nerve stimulation (VNS) following US Food and Drug Administration (FDA) approval of this intervention.
  
  
  METHODS
  We implanted a VNS device in 15 consecutive outpatients with treatment-resistant major depressive episodes, including 10 with major depressive disorder and 5 with bipolar disorder (DSM-IV criteria), between November 2005 and August 2006. Existing antidepressant treatment remained fixed as far as clinically possible. The primary outcome was change from baseline in the Beck Depression Inventory (BDI) score. Outcomes were assessed at 6 and 12 months postimplant and compared to those of the VNS pivotal efficacy trial that led to FDA approval of VNS.
  
  
  RESULTS
  The BDI score decreased significantly compared to baseline at 6 months (P < .05) and 12 months (P < .01), from a mean of 37.8 (SD = 7.8) before VNS activation to a mean of 24.6 (SD = 11.4) at 12 months. By 1 year, 28.6% (n = 4) of the sample responded to VNS and 7.1% (n = 1) remitted according to the BDI. Secondary outcomes on the Hamilton Depression Rating Scale 24-Item showed similar improvement at 1 year, with a 43% response rate (n = 6) and 14.3% remission rate (n = 2). No obvious predictors of response were detected. Side effects of VNS included hoarseness (73%), dyspnea (47%), nausea (40%), pain (33%), and anxiety (20%); no patient terminated treatment due to intolerable side effects.
  
  
  CONCLUSIONS
  We found that a substantial minority of patients with extremely difficult-to-treat depressive disorders benefited from VNS in an ambulatory clinical practice, with outcomes comparable to those observed in previous VNS efficacy studies and with a similar side effect profile.
authors.affiliation: Mood and Anxiety Disorders Treatment and Research Program, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. pilar.cristancho@uphs.upenn.edu
authors.forename: Pilar
authors.initials: P
authors.lastname: Cristancho
authors.forename: Mario A
authors.initials: MA
authors.lastname: Cristancho
authors.forename: Gordon H
authors.initials: GH
authors.lastname: Baltuch
authors.forename: Michael E
authors.initials: ME
authors.lastname: Thase
authors.forename: John P
authors.initials: JP
authors.lastname: O'Reardon
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000628:therapy; D003131:Combined Modality Therapy; D003865:Major Depressive Disorder / Q000628:therapy*; D061218:Depressive Disorder, Treatment-Resistant / Q000628:therapy*; D018795:Device Approval; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D057566:Self Report; D013997:Time Factors; D016896:Treatment Outcome; D055536:Vagus Nerve Stimulation / Q000009:adverse effects
chemical_list: D000928:Antidepressive Agents