Vagus nerve stimulation for depression: efficacy and safety in a European study.
BACKGROUND
Vagus nerve stimulation (VNS) therapy is associated with a decrease in seizure frequency in partial-onset seizure patients. Initial trials suggest that it may be an effective treatment, with few side-effects, for intractable depression.


METHODS
An open, uncontrolled European multi-centre study (D03) of VNS therapy was conducted, in addition to stable pharmacotherapy, in 74 patients with treatment-resistant depression (TRD). Treatment remained unchanged for the first 3 months; in the subsequent 9 months, medications and VNS dosing parameters were altered as indicated clinically.


RESULTS
The baseline 28-item Hamilton Depression Rating Scale (HAMD-28) score averaged 34. After 3 months of VNS, response rates (> or = 50% reduction in baseline scores) reached 37% and remission rates (HAMD-28 score <10) 17%. Response rates increased to 53% after 1 year of VNS, and remission rates reached 33%. Response was defined as sustained if no relapse occurred during the first year of VNS after response onset; 44% of patients met these criteria. Median time to response was 9 months. Most frequent side-effects were voice alteration (63% at 3 months of stimulation) and coughing (23%).


CONCLUSIONS
VNS therapy was effective in reducing severity of depression; efficacy increased over time. Efficacy ratings were in the same range as those previously reported from a USA study using a similar protocol; at 12 months, reduction of symptom severity was significantly higher in the European sample. This might be explained by a small but significant difference in the baseline HAMD-28 score and the lower number of treatments in the current episode in the European study.
Schlaepfer
T E
TE
Departments of Psychiatry, University Hospital, Bern, Switzerland. schlaepf@jhmi.edu
Frick
C
C
Zobel
A
A
Maier
W
W
Heuser
I
I
Bajbouj
M
M
O'Keane
V
V
Corcoran
C
C
Adolfsson
R
R
Trimble
M
M
Rau
H
H
Hoff
H-J
HJ
Padberg
F
F
Müller-Siecheneder
F
F
Audenaert
K
K
Van den Abbeele
D
D
Matthews
K
K
Christmas
D
D
Stanga
Z
Z
Hasdemir
M
M
D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D000928:Antidepressive Agents / Q000627:therapeutic use; D018692:Antimanic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D003131:Combined Modality Therapy; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D004599:Electric Stimulation Therapy / Q000009:adverse effects / Q000379:methods*; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010555:Personality Inventory; D012449:Safety; D016896:Treatment Outcome; D014630:Vagus Nerve / Q000503:physiopathology*
D000927:Anticonvulsants; D000928:Antidepressive Agents; D018692:Antimanic Agents