PDF
(Download)
|
- Ginkgo (Ginkgo biloba, Ginkgoaceae)
- EGb 761®
- Attention Deficit Hyperactivity Disorder
|
Date:
06-15-2015 | HC# 011562-522
|
Re: Ginkgo Extract Pilot Study Suggests Potential for Application in Childhood Attention Deficit Hyperactivity Disorder
Uebel-von
Sandersleben H, Rothenberger A, Albrecht B, Rothenberger LG, Klement S, Bock N. Ginkgo
biloba extract EGb 761® in children with ADHD. Z Kinder Jugendpsychiatr Psychother. September
2014;42(5):337-347.
Attention
deficit hyperactivity disorder (ADHD) affects children and is characterized by
inattention or lack of focus, disruptive behavior, and hyperactivity. Adverse
side effects or nonresponse associated with standard treatments have increased
the use of alternative therapies; however, knowledge on safety and efficacy of
botanical treatments for ADHD in children is important to assess any potential
herb-drug interactions and to enable physicians to make the best informed
decisions about patient care. Ginkgo (Ginkgo
biloba, Ginkgoaceae) has shown efficacy in treating cognitive impairment in
certain adult populations1 as well as tolerance and significant
improvements in children and adolescents with ADHD.2 This
observational study tested ginkgo leaf extract (EGb 761®; Dr.
Willmar Schwabe GmbH & Co. KG; Karlsruhe, Germany) for appropriate dosage
and efficacy in treating ADHD symptoms in children.
Patients
(24) with ADHD were enrolled from the Department of Child and Adolescent
Psychiatry at the University of Göttingen, Göttingen, Germany. From these, 4
patients did not participate due to consent problems or other disorders.
Included patients (20) ranged in age from 6-13 years (mean age 8.2 ± 1.6 years)
and were not taking methylphenidate (a standard medicine for ADHD) due to
preference or tolerance issues. Patients also attended "regular"
school and had an IQ of over 80. Those that had received standard medication in
the 2 weeks prior to the study, had seizures or other health problems causing
symptoms similar to ADHD, or suffered from other medical conditions were
excluded.
EGb
761 is a dry acetone extract of ginkgo leaves standardized to 22.0-27.0% flavonoids,
5.0-7.0% terpene lactones (2.8-3.4% ginkgolides A, B, and C, and 2.6-3.2% bilobalide),
and less than 5 ppm ginkgolic acids. Patients initially took 40 mg twice daily
for 1 week and increased their dosage successively to 60 mg and, after another week,
120 mg twice daily, if scores on an attention problem assessment were
indicative of continued relevant difficulties. The highest achieved dose was
taken for 3 additional weeks. Adverse side effects were documented by both
parents and patients with the Side Effects Rating Scale (SERS-D, mild effects
are rated as 1 and most severe effects are rated as 9).
The
primary outcome was change in the item "severity of attentive
problems" of the FBB-HKS questionnaire (this German rating scale contains
20 aspects of ADHD symptoms, assessed by parents) as an assessment of
attentiveness. Secondary outcomes included assessment of hyperactivity,
impulsiveness, and aggression as measured by the FBB-HKS and FBB-SSV (an
assessment of behavioral problems where parents rate symptoms according to
"strongly agree" or "strongly disagree") tests. The FaBel
assessment was used to gauge family life disruptions (a lower score indicates less
strains on family life). The KINDL and SDQ-D questionnaires (higher scores
indicate improvement) were used to assess quality of life and psychopathological
problems, respectively. A behavioral attention test known as the Continuous
Performance Test was also conducted; patients were instructed to act when they
detected a specific combination of letters. Electrophysiological recordings were
also used to assess cue-onset performance amplitudes.
The
dose of 120 mg daily was sufficient for 2 patients, while the other 18 patients
were administered 240 mg per day of EGb 761 for 3 weeks, after having taken 120
mg daily for 1 week. Three adverse side effects observed were considered
"mild," and while 2 were described as unrelated to the medication, 1
case of prolonged thrombin time was termed "unlikely related" to the
ginkgo extract. For all patients, the total FBB-HKS score was significantly
improved from baseline to endpoint of the study (1.9 ± 0.4 vs. 1.5 ± 0.7,
P<0.01). Individual categories of the assessment, including attention
problems, hyperactivity, and impulsiveness, were also significantly improved
(P<0.01, P=0.02, P<0.01, respectively). The total score for the FBB-SSV
was also significantly improved from baseline to endpoint (0.7 ± 0.3 vs. 0.6 ±
0.3, P<0.01).
The
SDQ-D score for prosocial behavior was improved from baseline to endpoint (6.5
± 2.4 vs. 7.6 ± 2.2, P<0.01), but no changes were seen in peer problems,
hyperactivity, or the emotion and conduct problem categories of the assessment.
A significant decrease in FaBel score, indicating improved quality of family
life, was observed from baseline to endpoint (11.7 ± 1.2 vs. 11.2 ± 1.2,
P<0.01), and an improvement in SERS-D scores of the patient-reported adverse
effects assessment was observed (33.1 ± 20.7 vs. 25.3 ± 22.4, P=0.02). Elevated
error with this assessment brings the significance between the SERS-D score
changes into question. The Continuous Performance Test suffered from
experimental errors, resulting in 35% of results being dropped from the final
analysis. Improvements in ADHD symptoms were positively related to changes in
electrophysiological recordings.
In
summary, significant changes were seen in attention and quality-of-life
assessments in patients with ADHD taking EGb 761. Although significant improvements
were noted in several of the assessments used in this study, it is mentioned
that additional assessments done in the patients' school settings would be
important additions in future studies. Other mentioned limitations include a
small sample size and short treatment duration, and no use of placebo or
randomization. Despite this, EGb 761 was well tolerated in patients that did
not use methylphenidate, suggesting its usage as an alternative or adjuvant to
this standard treatment. Future clinical trials will ideally incorporate the
randomized, double-blind, placebo-controlled format with a larger patient group
and further confirm dose-dependent efficacy of ginkgo for the treatment of ADHD
in children. This study was sponsored by Dr. Willmar Schwabe GmbH & Co. KG;
one of the authors (Klement) is an employee of the company.
—Amy C. Keller, PhD
References
1Blumenthal M, Goldberg
A, Brinckmann J, eds. Herbal Medicine:
Expanded Commission E Monographs. Austin,
TX: American Botanical Council; Newton, MA: Integrative Medicine
Communications; 2000.
2Salehi B, Imani R,
Mohammadi MR, et al. Ginkgo biloba
for attention-deficit/hyperactivity disorder in children and adolescents: a
double blind, randomized controlled trial. Prog
Neuropsychopharmacol Biol Psychiatry. February 2010;34(1):76-80.
|