Effects of pulse width and electrode placement on the efficacy and cognitive effects of electroconvulsive therapy.
BACKGROUND
While electroconvulsive therapy (ECT) in major depression is effective, cognitive effects limit its use. Reducing the width of the electrical pulse and using the right unilateral electrode placement may decrease adverse cognitive effects, while preserving efficacy.


METHODS
In a double-masked study, we randomly assigned 90 depressed patients to right unilateral ECT at 6 times seizure threshold or bilateral ECT at 2.5 times seizure threshold, using either a traditional brief pulse (1.5 ms) or an ultrabrief pulse (0.3 ms). Depressive symptoms and cognition were assessed before, during, and immediately, two, and six months after therapy. Patients who responded were followed for a one-year period.


RESULTS
The final remission rate for ultrabrief bilateral ECT was 35 percent, compared with 73 percent for ultrabrief unilateral ECT, 65 percent for standard pulse width bilateral ECT, and 59 percent for standard pulse width unilateral ECT (all P's<0.05 after covariate adjustment). The ultrabrief right unilateral group had less severe cognitive side effects than the other 3 groups in virtually all primary outcome measures assessed in the acute postictal period, and during and immediately following therapy. Both the ultrabrief stimulus and right unilateral electrode placement produced less short- and long-term retrograde amnesia. Patients rated their memory deficits as less severe following ultrabrief right unilateral ECT compared to each of the other three conditions (P<0.001).


CONCLUSIONS
The use of an ultrabrief stimulus markedly reduces adverse cognitive effects, and when coupled with markedly suprathreshold right unilateral ECT, also preserves efficacy. (ClinicalTrials.gov number, NCT00487500.).
Sackeim
Harold A
HA
Department of Biological Psychiatry, New York State Psychiatric Institute, New York, NY 10032, USA. has1@columbia.edu
Prudic
Joan
J
Nobler
Mitchell S
MS
Fitzsimons
Linda
L
Lisanby
Sarah H
SH
Payne
Nancy
N
Berman
Robert M
RM
Brakemeier
Eva-Lotta
EL
Perera
Tarique
T
Devanand
D P
DP
D000328:Adult; D000368:Aged; D003071:Cognition / Q000502:physiology*; D003865:Major Depressive Disorder / Q000503:physiopathology / Q000517:prevention & control / Q000628:therapy*; D004311:Double-Blind Method; D004565:Electroconvulsive Therapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D005260:Female; D006801:Humans; D008569:Memory Disorders / Q000209:etiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D012008:Recurrence; D012107:Research Design; D016896:Treatment Outcome