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- Rhodiola (Rhodiola rosea, Crassulaceae)
- Anxiety
- Stress
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Date:
06-15-2016 | HC# 121554-546
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Re: Rhodiola Extract Reduces Mild Anxiety and Stress in an Open-label Study
Cropley
M, Banks AP, Boyle J. The effects of Rhodiola
rosea L. extract on anxiety, stress, cognition and other mood symptoms. Phytother Res. December 2015;29(12):1934-1939.
Stress
and anxiety are common in college students. Rhodiola (Rhodiola rosea, Crassulaceae) root extract is used to regulate
anxiety, stress, fatigue, and depression. The purpose of this randomized,
open-label study was to evaluate the effects of rhodiola on self-reported mild anxiety
and stress in college students.
The
study was conducted at the University of Surrey; Guildford, Surrey, United
Kingdom. Subjects were healthy, nonsmoking students (n = 81, aged 18-35 years) who
scored > 30 on the Spielberger State-Trait Anxiety Inventory (STAI). Exclusion
criteria were as follows: (1) pregnancy or breastfeeding; (2) consumption of >
5/day caffeine-containing beverages; (3) color blindness; (4) clinically significant
hepatic or renal abnormality on preliminary lab tests; (5) body mass index >
33; (6) history of alcohol, narcotic, benzodiazepine, or other substance abuse
or dependence within the preceding 12 months; (7) positive alcohol breath test
at any visit; (8) use of any other medication that could interfere with study
outcome and/or study treatment within the 2 weeks or 5 half-lives preceding the
first treatment phase; (9) current or recent (within 3 months) participation in
another clinical trial studying any drug or device; and (10) any other
condition that could compromise the subject's participation in the study.
Subjects
were randomly assigned to the untreated control group (41 subjects) or to the
rhodiola treatment group (40 subjects, 1 of whom did not complete the study due
to use of another medication). The rhodiola group received 200-mg tablets of Vitano®
(also known as Vitango®; Dr. Willmar Schwabe GmbH & Co. KG;
Karlsruhe, Germany) twice daily, before breakfast and before lunch, for 14
days. Vitano is made from the proprietary rhodiola root extract Rosalin (WS®
1375; Dr. Willmar Schwabe GmbH & Co. KG), a 1.5-5:1 dry extract. [Note: Information
available online indicates that WS 1375 is a 60% per weight ethanolic extract,
with 1 tablet corresponding to 300-1000 mg of rhodiola root and rhizome as
needed to maintain chemical standardization.] The primary outcome measures were
anxiety (measured with the STAI) and stress (measured with the Perceived Stress
Scale). Secondary outcome measures were mood (measured with the Profile of Mood
States Inventory, which includes 6 subscales measuring various aspects of mood),
sleepiness (measured with the Milford Epworth Sleepiness Scale), sleep quality
(measured with the Leeds
Sleep Evaluation Questionnaire), reaction time (a measure of cognition;
evaluated with the simple reaction time test and the choice reaction time
test), attention (measured with the sustained attention to response test), and
speed of thinking (measured with the symbol digit processing test). Subjects
were evaluated at baseline, 4 hours after the initial dosing, on day 7, and on
day 14.
Treatment
compliance was 100%. Baseline measurements were similar between groups. There
were 4 adverse events (AEs) in the rhodiola group and 2 in the control group,
none of which were considered treatment-related. At 14 days, the rhodiola group
had significant decreases in anxiety and stress, controlling for baseline
values, compared with control (both P < 0.01). There was no significant
effect at earlier time points, though at 7 days, there was a possible
nonsignificant trend towards reduced anxiety and stress in the rhodiola group
(P = 0.08 and P = 0.06, respectively). On the Profile of Mood States Inventory,
at 14 days, the rhodiola group had significantly reduced scores on the anger (P
< 0.05), confusion (P < 0.01), and total negative mood (P < 0.01)
scales compared with control; reduced scores on the depression subscale (P <
0.01) were not time dependent. There were no significant differences between
groups on mood subscales measuring fatigue, tension, or vigor, nor on any
measure of sleep or cognitive performance (i.e., reaction, attention, and thinking
speed).
The authors conclude that
rhodiola (Vitano) extract is effective in treating mild anxiety and stress. They
also conclude that rhodiola has a general positive effect on mood, since it
improved some mood parameters, and that it has no effect on cognition. The
study has many limitations, including no placebo group and self-reported outcome
measures. The authors consider it unlikely that results were due to a placebo
effect because the benefits appeared over time and were not seen equally in all
mood subscales. However, an important limitation is that the authors do not
discuss the school schedules of the student subjects. Stress and anxiety could
decrease over a 2-week period as students adjust to new schedules, complete
exams, or look forward to a school recess, and it is unclear whether subjects
from the rhodiola and untreated control groups had comparable schedules and
stressors during the study period. A placebo group would have helped to resolve
these limitations. This research was supported by a grant from Dr. Willmar Schwabe
GmbH & Co. KG.
—Heather S. Oliff,
PhD
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