Vagus nerve stimulation (VNS) for major depressive episodes: one year outcomes.
BACKGROUND
Vagus nerve stimulation has shown promising results in an open, acute phase pilot study of adults in a treatment-resistant major depressive episode. This open, naturalistic follow-up study was conducted to determine whether the initial promising effects were sustained, and whether changes in function would be observed.


METHODS
Thirty adult outpatients in a treatment-resistant, nonpsychotic major depressive episode received an additional 9 months of vagus nerve stimulation treatment following exit from the 3-month acute study. Changes in psychotropic medications and vagus nerve stimulation stimulus parameters were allowed during this longer-term follow-up study. A priori definitions were used to define response (> or = 50% reduction in baseline Hamilton Rating Scale for Depression total score) and remission (Hamilton Rating Scale for Depression < or = 10).


RESULTS
The response rate was sustained [40% (12/30) to 46% (13/28); p =.317] and the remission rate significantly increased [17% (5/30) to 29% (8/28); p =.045] with an additional 9 months of long-term vagus nerve stimulation treatment after exit from the acute study (1 year total vagus nerve stimulation treatment). Significant improvements in function between acute study exit and the 1-year follow-up assessment as measured by the Medical Outcomes Study Short Form-36 were observed.


CONCLUSIONS
Longer-term vagus nerve stimulation treatment was associated with sustained symptomatic benefit and sustained or enhanced functional status in this naturalistic follow-up study.
Marangell
Lauren B
LB
Department of Psychiatry, Baylor College of Medicine, One Baylor Plaza, BCM 350, Houston, TX 77030, USA.
Rush
A John
AJ
George
Mark S
MS
Sackeim
Harold A
HA
Johnson
Christopher R
CR
Husain
Mustafa M
MM
Nahas
Ziad
Z
Lisanby
Sarah H
SH
D000328:Adult; D015331:Cohort Studies; D003866:Depressive Disorder / Q000523:psychology / Q000628:therapy*; D004599:Electric Stimulation Therapy / Q000009:adverse effects / Q000523:psychology*; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D013995:Time; D016896:Treatment Outcome; D014630:Vagus Nerve / Q000502:physiology*