Issue:
100
Page: 35-37
American Ginseng Root Clinically Safe and Effective for Reducing Cancer-Related Fatigue
by Amy C. Keller
HerbalGram.
2013; American Botanical Council
< lang="NL">Reviewed: Barton DL, Liu H, Dakhil S, et al. Wisconsin
ginseng (Panax
quinquefolius) to improve cancer-related fatigue:
a randomized, double-blind trial, N07C2. < lang="DE">J Natl Cancer Inst. August
2013;105(16):1230-1238.
Cancer-related
fatigue (CRF) can severely disrupt the lives of both those recovering from
cancer and patients currently receiving cancer treatment. Although standard
medications such as psychostimulants have been studied for the treatment of
CRF, clinical studies have not confirmed their efficacy. Both American ginseng
(Panax quinquefolius,
Araliaceae) and Asian ginseng (P. ginseng) have been used in Traditional
Chinese Medicine as adaptogens, among other uses. Compounds known as
ginsenosides, found in ginseng, are broadly bioactive.1 This
randomized, double-blind, placebo-controlled study was based on a prior
clinical pilot study of American ginseng for patients with CRF. In the pilot
study, American ginseng with 5% ginsenoside content was given to participants
in 750, 1000, or 2000 mg doses for eight weeks versus a placebo. The results
from that trial showed that 1000 and 2000 mgs of < lang="IT">P. quinquefolius were most
efficacious at four and eight weeks compared to placebo.2 Based on
these results, this larger study investigated the efficacy and tolerability of
2000 mg daily of American ginseng with a reported level of 3% ginsenosides in
patients with CRF. (The ginseng root material was further assessed for “quality” and
“potency” by an unnamed company.)
Enrolled
patients were randomly assigned to either active treatment (2000 mg daily of
ground American ginseng root commercially cultivated in Wisconsin) or a rice
powder placebo for eight weeks, taken in the morning and noon. American ginseng
and placebo were procured from the Ginseng Board of Wisconsin (Wausau, WI) and
produced with good manufacturing practices (GMPs) by Beehive Botanicals in
Hayward, WI.
Patients with CRF (having a score ≥ [greater than or equal to] four
using a scale ranging from 0=no fatigue to 10=severe fatigue) present one month
or more prior to the study were included as long as their cancer diagnosis was
made within the preceding two years. Patients with brain tumors or central
nervous system lymphoma and those with a score of four or higher for pain or
insomnia using the scale above were excluded. Also excluded were those taking
steroids, opioids, ginseng, or other treatments for fatigue. The randomization
process controlled for baseline fatigue, recurrent fatigue, cancer treatment
type and length, and tumor characteristics.
An
impact score on the Multidimensional Fatigue Symptom Inventory-Short Form
(MFSI-SF) at four weeks was the primary outcome. This scale rates fatigue from
0 (no fatigue) to four (extreme fatigue). Change in scores on the Profile of
Mood States (POMS) fatigue-inertia and vigor-activity subscales and the Brief
Fatigue Inventory (BFI) scale were secondary outcomes. These assessments were
administered at baseline, four, and eight weeks into the study. Patients
described the type and severity of adverse side effects at the study’s start and weekly thereafter. Study
administrators also gauged adverse side effects during clinic visits. Scales
from 0-10 were used to assess fatigue, pain, and sleep quality.
Initially,
364 patients were enrolled, with 133 patients in the treatment group and 128
patients in the placebo group completing the study (n=261). At the four-week
primary endpoint analysis, 147 patients were in the treatment group, and 153
patients were in the placebo group (n=300). At baseline, no differences were
observed between groups’ fatigue assessments or demographic measurements. At four
weeks into the study, the change in the MFSI-SF in those in the treatment group
was a non-significant difference of 14.4±27.1
as compared with 8.2±24.8 for those in
the placebo group (P=0.07). The difference in score change at eight weeks,
however, was significant (20±27 vs. 10.3±26.2,
treatment group vs. control group, respectively; P=0.003).
After
eight weeks of treatment, the MFSI-SF physical subscore change from baseline
was significantly greater in those in the treatment group as compared to the
placebo group (3.0±17.9 vs. -1.7±18.2,
P=0.004). This also was observed with MFSI-SF total score change from baseline
at the end of the study (6.7± 4.0 vs. 3.7±14.6,
P=0.02). The change from baseline in POMS fatigue inertia scores after eight
weeks of treatment also was significantly greater in the treatment group as
compared to the placebo group (18.6±24.8
vs. 10.2±26.1, P=0.008).
While
the BFI total score was not significantly different between groups, the
subscores for “worst fatigue” and “fatigue
now” after
eight weeks of treatment in the ginseng group were significantly improved as
compared to the placebo group (P value and data not reported). Additionally,
when only those patients undergoing cancer treatment were compared in both
groups, the percentage change in MFSI-SF score from baseline of those in the
treatment group was significantly more than that of the placebo group after
both four and eight weeks (P=0.02 and 0.01, respectively).
Adverse
side effects that occurred more frequently than 1% included agitation, anxiety,
insomnia, nausea, and vomiting, while nervousness, sleep disturbances, and
loose stools were also noted. The adverse effects of greater frequency were not
significantly different between groups, suggesting that American ginseng
supplementation seems well tolerated but does not alleviate adverse side
effects inherent to this population. Both loose stools and pain were worse
after baseline but occurred only in the placebo group over the course of the
study.
In
conclusion, this study reports the safety and efficacy of eight weeks of
American ginseng supplementation for the alleviation of CRF. The authors state
that these results were “clinically
meaningful” (more
than 10 points difference using a scale from 0 to 100). Due to the significant
improvement in fatigue in those undergoing current cancer treatment versus
those who had completed chemotherapy, American ginseng may be a possible
treatment for CRF. Stated strengths of the study include its randomized and
double-blind design, and that fatigue was distinguished from sleep deficit or
pain. The authors cited the study’s
limited duration and general difficulty of measuring fatigue as weaknesses.
Variations
among studies of efficacy measures — such
as improvement of BFI — may
be due to variable concentrations of ginsenosides, which can result from
agricultural inconsistencies and lack of content standardization during
processing. Ideally, future studies also should investigate potential herb-drug
interactions with chemotherapy. In summary, this study suggests that American
ginseng may be a well-tolerated treatment of CRF, particularly during cancer
treatment, for which no other pharmacotherapy has shown significant clinical
benefit.
—Amy C. Keller, PhD
References
1. Lewis WH, Elvin-Lewis MPF. Medical Botany: Plants
Affecting Human Health, 2nd ed. Hoboken, NJ: John Wiley &
Sons, Inc.; 2003.
2. Barton DL, Soori GS, Bauer BA, et al. Pilot study of < lang="IT">Panax quinquefolius (American
ginseng) to improve cancer-related fatigue: a randomized, double-blind,
dose-finding evaluation: NCCTG trial N03CA. Support Care Cancer.
2010;18(2):179-187.
|