Effects of 12 Months of Vagus Nerve Stimulation in Treatment-Resistant Depression: A Naturalistic Study

Authors

• A. John Rush, University of Texas Southwestern Medical CenterFollow
• Harold A. Sackeim, New York State Psychiatric InstituteFollow
• Lauren B. Marangell, Baylor College of Medicine
• Mark S. George, Medical University of South CarolinaFollow
• Stephen K. Brannan, Cyberonics Inc.
• Sonia M. Davis, Quintiles Inc.Follow
• Phil Lavori, Stanford UniversityFollow
• Robert Howland, University of Pittsburgh School of Medicine
• Mitchel A. Kling, University of Maryland School of Medicine
• Barry Rittberg, University of Minnesota Medical School
• Linda Carpenter, University of Texas Southwestern Medical Center
• Philip Ninan, Psychiatric Research Institute
• Francisco Moreno, St. Louis University Health Science Center
• Thomas Schwartz, SUNY Upstate Medical University at Syracuse
• Charles Conway, St. Louis University Health Science Center
• Michael Burke, University of Nebraska Medical Center
• John J. Barry, New York State Psychiatric Institute

Date of this Version

2005

Document Type

Article

Citation

Biological Psychiatry, Volume 58, Issue 5, 1 September 2005, Pages 355-363

Abstract

Background: The need for effective, long-term treatment for recurrent or chronic, treatment-resistant depression is well established.

Methods: This naturalistic follow-up describes outpatients with nonpsychotic major depressive (n = 185) or bipolar (I or II) disorder, depressed phase (n = 20) who initially received 10 weeks of active (n = 110) or sham vagus nerve stimulation (VNS) (n = 95). The initial active group received another 9 months, while the initial sham group received 12 months of VNS. Participants received antidepressant treatments and VNS, both of which could be adjusted.

Results: The primary analysis (repeated measures linear regression) revealed a significant reduction in 24-item Hamilton Rating Scale for Depression (HRSD₂₄) scores (average improvement, .45 points [SE = .05] per month (p < .001). At exit, HRSD₂₄ response rate was 27.2% (55/202); remission rate (HRSD₂₄ ≤ 9) was 15.8% (32/202). Montgomery Asberg Depression Rating Scale (28.2% [57/202]) and Clinical Global Impression-Improvement (34.0% [68/200]) showed similar response rates. Voice alteration, dyspnea, and neck pain were the most frequently reported adverse events.

Conclusions: These 1-year open trial data found VNS to be well tolerated, suggesting a potential long-term, growing benefit in treatment-resistant depression, albeit in the context of changes in depression treatments. Comparative long-term data are needed to determine whether these benefits can be attributed to VNS.