Ziad Nahas, MD, MSCR; Lauren B. Marangell, MD; Mustafa M. Husain, MD; A. John Rush, MD; Harold A. Sackeim, PhD; Sarah H. Lisanby, MD; James M. Martinez, MD; and Mark S. George, MD
Background: Vagus nerve stimulation
(VNS) had antidepressant effects in an initial open,
acute phase pilot study of 59 participants in a
treatment-resistant major depressive episode
(MDE). We examined the effects of adjunctive VNS
over 24 months in this cohort.
Method: Adult outpatients (N = 59)
with chronic or recurrent major depressive disorder
or bipolar (I or II) disorder and experiencing a
treatment-resistant, nonpsychotic MDE (DSM-IV criteria) received 2 years of VNS. Changes in
psychotropic medications and VNS stimulus parameters were allowed only after the first
3 months. Response was defined as > = 50% reduction from the baseline 28-item Hamilton
Rating Scale for Depression (HAM-D-28) total
score, and remission was defined as a HAM-D-28
score < = 10.
Results: Based on last observation
carried forward analyses, HAM-D-28 response rates
were 31% (18/59) after 3 months, 44% (26/59) after
1 year, and 42% (25/59) after 2 years of
adjunctive VNS. Remission rates were 15% (9/59) at
3 months, 27% (16/59) at 1 year, and 22% (13/59) at 2 years. By 2 years, 2 deaths (unrelated
to VNS) had occurred, 4 participants had withdrawn from the study, and 81% (48/59) were still
receiving VNS. Longer-term VNS was generally well tolerated.
Conclusion: These results suggest that
patients with chronic or recurrent,
treatment-resistant depression may show long-term benefit
when treated with VNS.
J Clin Psychiatry 2005;66(9):1097-1104
© Copyright 2005 Physicians Postgraduate Press, Inc.