APA is preparing to publish a major revision of its guideline on the
practice of electroconvulsive therapy (ECT) next year. The new edition will
contain substantially updated recommendations, according to members of the
task force in charge of revising the guideline.
Members of APA's Task Force to Revise the Practice of Electroconvulsive
Therapy gave an update on the current evidence for the efficacy and safety of
ECT at APA's 2009 annual meeting in San Francisco in May.
Clinical topics discussed by task force members included optimal electrode
placement, informed consent and documentation, stimulus dosing, and
relapse-prevention strategies.
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The task force members have been reviewing the latest research evidence in
weekly teleconferences and collecting feedback from clinicians for this
revision, explained task force chair Sarah Lisanby, M.D., a professor of
psychiatry at Columbia University and the chief of the Columbia Brain
Stimulation and Therapeutic Modulation Division. The guideline will also
contain proposals for training and certification for ECT practice, the task
force members noted.
Charles Kellner, M.D., a professor of psychiatry at Mount Sinai School of
Medicine, discussed the continuing debate over the optimal electrode
placement. The current guideline recommends that practitioners "should
be skilled in administering both unilateral and bilateral ECT," and the
placement choice "should be based on an ongoing analysis of applicable
risks and benefits" and on consultation with the psychiatrist, the
person giving consent, and the attendant physician. In recent years, the use
of bifrontal electrode placement has gained popularity, he noted.
In a recently completed study conducted by the Consortium for Research in
ECT (CORE) and funded by the National Institute of Mental Health, 230 patients
were randomized to receive right unilateral (RUL) ECT treatments at six times
the seizure threshold, bifrontal (BF) ECT at 1.5 times the seizure threshold,
and bilateral (BL) ECT also at 1.5 times the seizure threshold, Kellner said.
The rates of remission were 55 percent for RUL, 61 percent for BF, and 64
percent for the BL treatment. The rates of response were 73 percent, 79
percent, and 82 percent, respectively. These results were not statistically
significant among the treatment arms. Looking at the changes in symptoms over
the treatment courses, however, "the bitemporal ECT gets patients well
more quickly than the other two electrode placements," Kellner pointed
out, and this difference was statistically significant.
Meanwhile, the cognitive effects of each placement require further
research. "Although it is pretty clear that bilateral electrode
placements are a little bit more effective than right unilateral, and right
unilateral placement causes less cognitive impairment for many patients, we're
still not able to predict exactly the outcome or side effects for a particular
patient," he said. Kellner and most attendees agreed that, if a patient
is severely ill, suicidal, or urgently needs symptom relief, bilateral ECT is
a favored placement choice.
Another controversial issue is whether the electrode placement should be
explicitly mentioned in the informed consent and whether informed consent
should be obtained again if the placement is changed due to treatment failure.
Attendees expressed divergent opinions based on their own ECT practice.
Since patients have different seizure thresholds, a titration-based
stimulus dosing strategy, in which the electric charge applied for each
patient is adjusted to his or her individual seizure threshold, is better than
fixed-charge dosing, in which the same electric charge is given to every
patient, according to Andrew Krystal, M.D., a professor of psychiatry at Duke
University School of Medicine.
Some physicians use an age-based dosing algorithm to calculate the
estimated seizure threshold before administering ECT rather than specifically
titrating the electrical charge in each patient during the procedure. Because
a higher charge above the seizure threshold is associated with a higher degree
of cognitive side effects in both RUL and BL placements and people vary
substantially in their individual seizure threshold, dosage titration is the
more appropriate approach to optimize outcome, said Krystal.
Prior research studies have mostly used six to eight times the seizure
threshold for RUL ECT. Krystal cited a 2002 study by W. Vaughn McCall, M.D.,
and colleagues indicating that RUL ECT given at eight times seizure threshold
produced cognitive impairment and antidepressant effect similar to BL ECT at
1.5 times the seizure threshold.
Ultra-brief pulses given at 0.25 or 0.3 milliseconds are also an area of
research interest, as this approach may produce efficacy similar to that
achieved by conventional pulses (1.5 milliseconds) but may reduce cognitive
side effects. Harold Sackeim, Ph.D., and colleagues conducted a study of 90
patients who were randomized to four groups that compared RUL with BL and
ultra-brief pulse with standard pulse. Their results were published in the
January 2008 Brain Stimulation.
The ultrabrief-pulse RUL ECT at six times the seizure threshold produced
the highest remission rate (73 percent) and the least cognitive impairment
compared with standard BL (2.5 times the seizure threshold), standard RUL, and
ultrabrief BL. Unexpectedly, the patients on ultrabrief BL did the worst in
terms of efficacy, with only 35 percent reaching remission. "It's an
exciting, interesting emerging story," said Krystal, but a lot more
evidence is needed to answer many questions about finding the best treatment
with the lowest risk.
In addition, how to maintain the impressive response and remission rates
after acute ECT and not lose ground to relapse remains an unresolved clinical
question. Mustafa Husain, M.D., a professor of psychiatry and internal
medicine at the University of Texas Southwestern Medical Center in Dallas,
presented a 2007 study by CORE of 200 patients who had achieved remission
after acute ECT. The patients were randomized to either maintenance ECT,
gradually tapered to once a month, or to pharmacotherapy with lithium and
nortriptyline. The six-month relapse rates did not differ significantly
between the two treatments, with 32 percent on pharmacotherapy and 37 percent
on maintenance ECT relapsing. Overall, 46 percent of patients on either
treatment maintained their remission while the rest either relapsed or dropped
out.
Other options for maintenance, such as combining maintenance ECT and
pharmacotherapy and administering ECT as needed based on symptoms and
algorithms, are being used in practice and need more study. Emerging
neurostimulation treatments, such as transcranial magnetic stimulation, may
offer additional options for relapse prevention, Husain said. ▪