Electromedicine CES in the Treatment of Depression, Part 2 This second article, of a two-part series on the efficacy of Cranial Electrotherapy Stimulation (CES) in treating depression, reviews the results of meta-analysis conducted on CES studies.
By Daniel L. Kirsch, PhD, DAAPM, FAIS and Marshall F. Gilula, MD
Cranial electrotherapy stimulation them with three, 30 minute CES sessions in an open clinical trial.
This did not reduce depressive symptoms so stimulation was in-
creased to a minimum of five, 30 minute sessions. At this level,
vices using microcurrent levels of electri-
measurable changes began to be seen. CES is now routinely pre-
scribed for depression for a minimum of three weeks of daily
treatment followed by a reduced schedule or for use on an as-
Some of the early studies are suited to meta-analysis in that
ing tiny electrical currents—similar to
scores on pre- and post-testing were given, using psychometric
instruments such as the Zung Self Rating Depression Scale.
Often other information was added such as the percent of pa-
tients who improved at least 50%, those who did not improve at
form, moves electrons through the brain at a variety of frequen-
all, and those who demonstrated signs of other responses. That
cies collectively known as harmonic resonance. This normalizes
form of data is a poor fit with meta-analysis.
the electrical activity of the brain as measured by an electroen-
Following the often dramatic results published by Rosenthal,
cephalogram (EEG). The patient undergoing CES treatment will
other researchers began studying psychiatric inpatients. Such
often report a pleasant, relaxed feeling of well-being. Improve-
patients were all heavily medicated as well. Accordingly, CES
ment is usually experienced during treatment, but may be seen
would be required to demonstrate effects over and above the ef-
hours later, or even the day after treatment. Depression control
fects of medications, and that was usually found.
is often experienced after two to three weeks of daily treatment. Ear clip electrodes, moistened with an appropriate conducting
Complications in Some CES Test Protocols
solution, are applied for 20 minutes to an hour or more on an
Feighner was one of the early CES research pioneers working
initial daily basis for 3-6 weeks, followed by a reduced schedule
with psychiatric inpatients. He ran into two complications: pa-
of 2 or 3 treatments a week until the depression is resolved, and
tients were heavily medicated, and a crossover design was uti-
then further reduced to an as-needed (p.r.n.) basis.
lized. Adding to that, the patients were treated 30 minutes daily
This article focuses on the meta-analysis of CES studies of de-
for only five days.5 Only pre-crossover scores from that study are
pression along with a discussion of individual study designs and
included in the meta-analysis since they are the only statistical-
outcomes. It is important to note that protocols for some CES
ly legitimate data as explained in the discussion of meta-analy-
studies were poorly designed; inconsistent patient selection and
sis in the previous issue of Practical Pain Management.6
concurrent use of other pharmaceutical modalities rendered the
Marshall subsequently studied inpatients in a state hospital
results inconclusive with regard to CES efficacy in treating de-
by, once again, providing CES for 30 minutes a day for only five
pression. The authors have carefully selected only valid studies
days. Here again, both the treatment and control subjects were
to provide the most complete and accurate meta-analysis of CES
heavily medicated. The study became invalid when the controls
showed a substantial improvement in their depression duringthe course of the study, and there was no control group left
Early CES Studies In Treating Depression
against whom the treatment effect of CES could be measured.7
Rosenthal conducted some of the earliest CES studies of depres-
CES studies that were invalidated due to a loss of controls were
sion when CES was first introduced in the U.S. His work was
often published, including the Marshall study and one by Passi-
primarily with psychiatric outpatients, although he sometimes
ni, who repeated a similar protocol in 1976 with an inpatient sam-
used medical staff as controls. He was basically trying to find out
ple that included a wide variety of diagnoses including addiction
what, if anything, CES treatment would do for his patients, how
and psychosis. All patients also received psychotropic medication,
many sessions it might require, and what level of current it took
and the study showed an improvement in depression following
14 days of daily CES for 30 minutes along with medications. This
The early U.S protocols studied patients who had been refrac-
study had no controls with which to measure treatment effects and
tive to previous antidepressant treatment, but only provided
was thereby invalidated, but that did not prevent it from being
2007 PPM Communications, Inc. Reprinted with permission.
published. The authors concluded that since all of the sham treat-
assessed on the National Institutes of Mental Health (NIMH)
ed patients improved, improvement from CES treatment could
Self Rating Scale and obtained a 73% reduction in depression
only be attributed to the placebo effect.8
among the treated patients compared with a 21% improvement
Levitt studied six male and seven female psychiatric inpatients,
divided into two groups, with diagnoses of schizophrenia, alco-
Shealy studied depression in chronic pain patients and con-
holism, psychotic depression, mixed neurosis and personality dis-
trols. He found that CES therapy yielded a 60% improvement in
orders. Two of the CES devices malfunctioned, and this reduced
their depression score and there was a significant elevation in
his treated group to five who received treatment 30 minutes a
serotonin (mean of 33.18 ± 9.33 pre-test to 44.64 ± 9.10 post
day for ten sessions over a two week period. They were all on psy-
test, P<.0089), and a significant decrease in cholinesterase (mean
chotropic and sleep medications. Some sham treated patients im-
of 13.82 ± 2.86 pre-test to 10.45 ± 3.04 post test, P<.0067).15
proved as did some CES patients, and some saw their conditions
Lichtbroun and, later, Tyers began a series of studies of de-
worsen. This was essentially a negative outcome from the point
pression in fibromyalgia patients.16-18 They measured depression
of view of CES treatment effectiveness. It should be noted how-
with the POMS test and found that as the patients’ pain scores
ever, that in addition to the medications, Levitt was using an early
improved, so did their depression which showed between 26%
style of CES electrodes in which saline soaked gauze pads
to 35% improvement after three weeks of daily, 60 minute CES
wrapped around thin steel plates were placed tightly over the
closed eyes. This provided undesirable visual effects such as
Two other groups of depressed subjects studied were gradu-
blurred vision.9 Subjects in both groups reported the temporary
ate students in a business school suffering under the stress of
visual disturbances which were later judged to be caused by me-
completing an MBA program and patients suffering from life-
chanical pressure on the eyes, not the electrical intervention it-
time disability due to closed head injuries.19,20 Both were double-
self. This electrode method was abandoned over 30 years ago.
blind studies in which CES or sham CES was given for one hourdaily, Monday through Thursday for three weeks in the closedhead injured subjects and one hour daily for 21 days in the grad-
“…with an effect size of r =.50, CES is much more
uate students. The closed head injured subjects achieved a 30%
effective than any antidepressant medication, and,
improvement in their depression while the graduate studentsimproved 34%. unlike them, lacks significant adverse effects.”
A group of 28 children and adults with attention deficit dis-
order (ADD) were studied in an open clinical protocol that
Improved Study Methodology
looked at various factors, including depression scales. They were
In 1975, a depression study was conducted with 72 inpatient al-
given 45 minute daily CES treatments for three weeks. They were
coholics who were provided 15 daily CES treatments, 40 minutes
retested at 18 months follow up. Their depression improved by
a day at a current level just below sensory threshold (sub-senso-
32% at the conclusion of the study, and was maintained at that
ry). This length of treatment was chosen because of some of
Rosenthal’s earlier difficulties, and because most of the patients
Physicians evaluated 500 patients who were treated with CES,
were also taking psychotropic medications. Their depression, as
69 of whom carried a primary depression diagnosis with the bal-
measured on the Profile of Mood States (POMS) improved 76%
ance having comorbid depression. The group improved an av-
while the sham-treated patients continued to worsen.10
erage of 71% over varying courses of treatment.22 Another study
Krupitsky’s group at Yale studied affective disturbance in 20
examined patients’ own self rating of improvement. This infor-
alcoholic patients in 1991, and found an average of 28% im-
mation was obtained from surveys of 318 patients who had been
provement on two depression measures. They concluded that
diagnosed with depression and who had used their Alpha-Stim
CES was an effective non-pharmacological method to treat af-
CES device for at least three weeks prior to sending in the sur-
fective disturbances in alcoholic patients in remission.11
vey. They rated their improvement an average of 58% on a 100
May also studied inpatient addicts and found that 60 minutes
point scale. While 12% rated their improvement less than 25%,
of CES for 25 days allowed the patients to attain an unprece-
more than twice as many (27%) rated their improvement be-
dented recovery record, with the group of 14 patients improv-
ing 76% on the Multiple Affect Adjective Check List and im-
Two additional crossover studies were done, one in which sham
proving 77% on the Beck Depression Inventory.12 This was the
treated patients were actually given CES at a low current while
longest treatment time studied to date. Although based on a suc-
treated patients were provided CES at a higher current, after
cessful pilot study, the U.S. government has now funded a six
which they were crossed over.24 No improvement was noted in
month CES treatment study for veterans with spinal cord in-
the study, although there were protocol design flaws. Another
double-blind crossover design, in which five 30 minute treat-
The final addiction study to date that included data on de-
ments were given, provided results in the patients prior to the
pression was a doctoral dissertation in 1994 by Bianco who stud-
crossover, allowing its use in meta-analysis.25
ied 65 inpatient poly-substance abusers. He provided 45 min-utes of CES daily from 6 to 14 days, and found their improve-
Studies Collected For Meta-Analysis
ment on the Beck Depression Inventory to be 80%.13
Table 1 presents all of the studies collected for meta-analysis.
Hearst studied 28 psychiatric outpatients who were on less
There were a total of 23 suitable CES studies of depression, rep-
medication than a typical inpatient sample. Because the study
resenting some 1,075 subjects studied. It bears emphasis in this
took place in 1974, the early protocol of five, 30 minute treat-
day of black box warnings on SSRI’s that none of the CES stud-
ment or sham treatment sessions was followed. The patients were
ies found any significant negative side effects. CES is known to
2007 PPM Communications, Inc. Reprinted with permission. TABLE 1. LIST AND DESCRIPTION OF DEPRESSION STUDIES Blinding Primary Diagnosis Therapist Assessor Study Design OutcomeMeasure
a Zung’s Self Rating Depression Scaleb Profile of Mood Statesc Multiple Affect Adjective Check Listd Montgomery and Asberg Depression Rating Scale
produce skin irritation at the electrode site in people with light
jects to use for subsequent crossover sham treatment. That leaves
skin and may cause an occasional headache. Such side effects
20 studies involving 937 subjects that are considered valid for
Table 2 presents the studies shown in Table 1, with three of
the studies removed. In one, the study was invalidated when the
Secondary Analysis of Studies
sham treated patients also improved.8 The other two studies had
Some studies reported more than one measure of depression.
crossover designs, and the investigators did not report the treat-
Feighner reported two measures, as did Krupitsky, May and
ment results prior to the crossover. The sham patients in a
Rosenthal (in three different studies), while Moore reported
crossover design who had active CES during the initial arm of
three. In order to limit the input of error variance from any given
the study typically continue to improve, making them unfit sub-
study, each study was represented with only one score, and to be
2007 PPM Communications, Inc. Reprinted with permission. TABLE 2. AN INITIAL ANALYSIS OF STUDIES SHOWN IN TABLE 1 Number of Patients Controls Statistic Reported Zr Scorea
a From Fisher Tables of r to zr transformation26
b Percent change equals r, from the binomial effect size distribution. From Wolf27
equitable, means of all the scores given were computed and uti-
size obtained is more than sufficient to show that CES is a very ef-
lized. Since percentages can not be legitimately averaged, they
fective treatment for depression. In fact, with an effect size of r
were converted to Zr scores and then those scores were aver-
=.50, CES is much more effective than any antidepressant med-
aged. The mean Zr score was then converted back into a per-
ication, and, unlike them, lacks significant adverse effects.6,29
cent score. The results of this for CES in the treatment of de-
To estimate the outer limits of the effect size to be expected
in any future meta-analyses of studies of CES for depression, the
The effect size from the 20 studies analyzed is r =.50, which is
confidence interval of the effect size needs to be derived. That
considered a strong effect size. While there was a wide disparity
is calculated from the standard deviation, divided by the square
of number of subjects in the various studies, an N weighted effect
root of the number of studies in the analysis, yielding the stan-
size of r =.51 was obtained, showing that the number of people
dard error of the mean. The resulting score indicates that if 15
appearing in a given study was relatively unimportant. The effect
additional meta-analyses of 21 studies each is performed in the
2007 PPM Communications, Inc. Reprinted with permission. TABLE 3. A SECONDARY ANALYSIS OF STUDIES SHOWN IN TABLE 1
depression scores of the controls in eachstudy. Table 4 presents an abbreviated ver-
Number of Patients
sion of those results, from which the ef-fect size for fluoxetine treatment of de-
Controls Total Statistic Reported Results Zr Scorea
group by the change in the treated group,then subtracted that score from 100 to get
over and above that of the placebo pa-tients.
fect of fluoxetine over and above that of
the placebo patients in the five studies wasonly 8%. In study 25, the placebo group
ed patients. That figure rose to 11% whenthe studies were corrected (weighted) for
sample size. Kirsch also evaluated otherantidepressant drug studies that were sent
searchers added subjects to their studies
based on the Hamilton Depression Scale,a psychometric paper and pencil test that
either the patient or the researcher cancomplete. Tests with similar validity and
reliability were used in the CES studies.
So from the standpoint of enlisting sub-jects, identical or similar diagnostic de-
vices were used for both the pharmaceu-tical and CES research.
would not be expected to improve as dra-matically in the placebo condition as did
the placebo patients in all the pharma-ceutical studies reported to the FDA. Or
to put it another way, one would not an-ticipate that 89% of placebo patients with
weeks or less as they did in the fluoxetine
studies. Most were recruited by advertise-
Effect Size Confidence Limits, p<.01=.32-.68
ments in newspapers and other media.
a From Fisher Tables of r to zr transformation26
b Percent change equals r, from the binomial effect size distribution. From Wolf27
c From Rosenthal28d The first two columns do not add to this figure due to subjects in the crossover studies appearing twice
future (more than 300 additional studies),
there is a 99% likelihood that the effect
care (i.e., antidepressant medications).
size obtained will fall within an effect size
were either more serious cases of depres-
Comparison To Efficacy of
proval of fluoxetine (Prozac).30 Five stud-
cals were typically studied over a longer
Antidepressant Fluoxetine
ies were submitted, which Kirsch analyzed
to determine how the effectiveness of CES
pression scores experienced by the treat-
2007 PPM Communications, Inc. Reprinted with permission. Summary of CES Modality For Depression TABLE 4. EFFECTIVENESS OF FLUOXETINE OVER AND ABOVE
The following presents a brief synopsis of the discussion in parts1 and 2 of this series. PLACEBO EFFECT IN TREATING DEPRESSION
• Cranial Electrotherapy Stimulation (CES) can occasionally
be a single, time-limited treatment of many mild depres-
sions with or without concomitant medication.
• Meta-Analysis is a valid way to assess the effect size of
• Meta-Analysis of effect size has shown that CES, with and
without concomitant medication, compares very favorably
with the effect size of medication treatment.
• Although CES is nearly free of significant adverse effects,
there is a spectrum of usually mild cutaneous irritativeeffects at the electrode site which can limit treatment
• Depressive disorders require competent medical evalua-
tion to rule out a primary or comorbid substance-related
effect or a primary or comorbid treatable medical illness.
• Neither CES nor antidepressants should be employed for
treatment without continuing and competent healthcaresupervision because of emerging suicidality as some
Conclusion
Regardless of the manner in which one analyzes CES studies of
• CES should always be considered as an add-on to medica-
depression, a moderate to strong effect size is revealed, which
tions before considering the more invasive Vagal Nerve
exceeds the results of antidepressant drug studies submitted to
Stimulator (VNS) or Deep Brain Stimulation (DBS)
the FDA for marketing approval (see Table 4).
because it is much cheaper and potentially as efficacious,
With moderately severe and severe depressions, CES should
definitely be considered as an add-on modality because of the
2007 PPM Communications, Inc. Reprinted with permission.
potential for (a) synergizing the efficacy
tionale Ärztegesellschaft für Energiemedizin,
10. Smith RB and O’Neill L. Electrosleep in the man-agement of alcoholism. Biological Psychiatry. 1975.
of the drug (s), and (b) reducing the over-
Austria 2000, in German. Best known for de-
all adverse effects of psychopharmaceuti-
signing the Alpha-Stim CES and MET line of
11. Krupitsky EM, Burakov AM and Karandashova GF
medical devices, Dr. Kirsch is Chairman of
et al. The administration of transcranial electric treat-
Electromedical Products International, Inc. of
ment for affective disturbances therapy in alcoholic pa-tients. Drug and Alcohol Dependence. 1991. 27:1-6. Mineral Wells, Texas, USA with additional of-
12. May B and May C. Pilot project using the Alpha-
fices in Europe and Asia. Dr. Kirsch can be
Stim 100 for drug and alcohol abuse. In: Kirsch,
tabolizing SSRI’s, other antidepressants,
Daniel L. (Ed) The Science Behind Cranial Elec-trotherapy Stimulation. Edmonton, Alberta, Canada. Marshall F. Gilula, M.D. is a Diplomate of
Medical Scope Publishing. 2002. p 51. the American Board of Psychiatry and Neurol-
13. Bianco F. The efficacy of cranial electrotherapy
It’s important to stress that adjunctive
ogy and a Diplomate of the American Board ofstimulation (CES) for the relief of anxiety and depres-Medical Electroencephalography. He is also asion among polysubstance abusers in chemical de-pendency treatment. Ph.D. dissertation, The Universi-
drug can often prevent the need for using
board-certified Instructor in Biofeedback andNeurotherapy (NBCB). In 1978 he was a US-
14. Hearst ED, Cloninger CR, Crews EL and Cadoret
quently the case in the currently accept-
USSR NIMH Exchange Scientist working with
RJ. Electrosleep therapy: a double-blind trial. Archives of General Psychiatry. 1974. 30(4):463-466. cranial electrotherapy stimulation and gener-
15. Shealy CN, Cady RK, Wilkie RG, Cox R, et Al. De-
can prove increasingly cost-effective com-
al psychophysiology techniques at the P.K.
pression: a diagnostic, neurochemical profile and
Anokhin Institute, Soviet Academy of Medical
therapy with cranial electrical stimulation (CES). Jour-nal of Neurological and Orthopaedic Medicine and
SSRI’s. CES can be an ideal treatment for
Sciences, Moscow. In 1983 Dr. Gilula was theSurgery. 1989. 10(4):319-321. first Motoyama-Ben Tov Fellow at the Institute
16. Lichtbroun AS, Raicer MMC and Smith RB. The
of Life Physics, Tokyo (Mitaka-shi), Japan and
treatment of fibromyalgia with cranial electrotherapy
sizes having the patient take the initiative
researched neuroelectric methodology and the
stimulation. Journal of Clinical Rheumatology. 2001. 7(2):72-78.
on a daily basis. This involves several be-
EEG of altered states with Professor Hiroshi
17. Tyers S and Smith RB. A comparison of cranial
Motoyama. Dr. Gilula has had four years of
electrotherapy stimulation alone or with chiropractic
residency and postdoctoral fellowship training
therapies in the treatment of fibromyalgia. The Ameri-can Chiropractor. 2001. 23(2), 39-41.
more education of clinicians and their pa-
in psychiatry and over seven years of postdoc-
18. Tyers S and Smith RB. Treatment of fibromyalgia
tients about the modality—especially due
toral training in neurology (neurophysiology
with cranial electrotherapy stimulation. The Original
to an initial aversion to electric stimula-
and epilepsy). He has 40 years of experience
tion because of a mental association with
in clinical psychiatry, and was in the Depart-
19. Matteson MT and Ivancevich JM. An exploratoryinvestigation of CES as an employee stress manage-
“Electric Shock” (Electroconvulsive Ther-
ment of Neurology at the University of Miami
ment technique. Journal of Health and Human Re-School of Medicine from 1999 through 2003.source Administration. 1986. 9:93-109.
cially because of the less onerous econom-
Dr. Gilula was a Senior Fellow, Miami Center
20. Smith RB, Tiberi A and Marshall J. The use of cra-
ics involved and the superior safety fac-
for Patient Safety, Department of Anesthesiol-
nial electrotherapy stimulation in the treatment ofclosed-head-injured patients. Brain Injury. 1994. ogy, University of Miami from 2003 through2005. Dr. Gilula is President and CEO of the
21. Smith RB. Cranial electrotherapy stimulation in
Life Energies Research Institute in Miami. He
the treatment of stress related cognitive dysfunction,with an eighteen month follow up. Journal of Cogni-
tions of the Vagal Nerve Stimulator (VNS)
can be reached at [email protected].tive Rehabilitation. 1999. 17(6):14-18.
22. Kirsch DL. Postmarketing survey of Alpha-Stim
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