Can Rhodiola Crenulata Intake Improve Oxygen Saturation and Decrease the Incidence of Acute Mountain Sickness

Study Overview
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Brief Summary
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Traditional folk medicine in the Arctic and Himalayan areas used Rhodiola species to enhance physical endurance, prevent aging, resist acute mountain sickness (AMS), and to treat fatigue, depression, anemia, impotence and respiratory infections. Rhodiola crenulata are widely used to prevent AMS in Himalayan areas and Lhasa in Tibet but none was examined by human study. The investigators conducted a randomized, double blind, placebo controlled, crossover study to investigate the efficacy of Rhodiola crenulata in preventing AMS.

Detailed Description
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The number of people traveling to altitude for work or for recreation is rising, and increased media attention towards these activities has also raised the profile of altitude related illness. The most effective preventive measure for acute mountain sickness (AMS)-gradual ascent-is frequently difficult or impractical for modern international travel to locations such as Lhasa in Tibet (3650 m) and La Paz in Bolivia (3740 m). In order to solve this problem, prophylactic acetazolamide was most commonly used. But prescription needed and side effects such as paresthesia and nausea are the disadvantage of using acetazolamide. Some over-the-counter herbal supplements with essentially no adverse effect were widely used, such as Rhodiola species. Rhodiola crenulata are widely used to prevent AMS in Himalayan areas and Lhasa in Tibet but none was examined by human study. The investigators conducted a randomized, double blind, placebo controlled, crossover study to investigate the efficacy of Rhodiola crenulata in preventing AMS.

Official Title
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Can Rhodiola Crenulata Intake Improve Oxygen Saturation and Decrease the Incidence of Acute Mountain Sickness.

Conditions
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Acute Mountain Sickness, Environmental Illness

Intervention / Treatment
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* Drug: Rhodiola crenulata
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 20 and 55 years. able to complete the study protocol of 9-day study regimens and mountain climbing twice. no prophylactic medication or herb one month before ascent. maintaining the same living conditions and habits four months before the first mountain climbing and four months between two mountaineering. living in the same altitude or within a difference of 200 meters. no additional physical training. no plan to gain or loss weight. no altitude exposure above 2500m. Exclusion Criteria: any history of chronic obstructive pulmonary disease, heart failure, cerebral neoplasm, mania, renal or hepatic insufficiency. women in pregnancy or intending of pregnancy during the 4-month study period.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Rhodiola crenulata-placebo sequence<br>Rhodiola crenulata for the first treatment period and placebo for the second treatment period, with a washout period of 4 months. Overall study population were 120 subjects, who were randomised and allocated into 2 sequences. | Drug: Rhodiola crenulata<br>* Rhodiola crenulata:capsules, 800 mg daily for 7 days before ascent and 2 days during mountaineering<br>* Other names: Hong Jing Tian;Drug: placebo<br>* Placebo:capsules, 800 mg daily for 7 days before ascent and 2 days during mountaineering<br>* Other names: Starch;|
| Active Comparator: Placebo-Rhodiola crenulata sequence<br>Placebo for the first treatment period and Rhodiola crenulata for the second treatment period, with a washout period of 4 months. Overall study population were 120 subjects, who were randomised and allocated into 2 sequences. | Drug: Rhodiola crenulata<br>* Rhodiola crenulata:capsules, 800 mg daily for 7 days before ascent and 2 days during mountaineering<br>* Other names: Hong Jing Tian;Drug: placebo<br>* Placebo:capsules, 800 mg daily for 7 days before ascent and 2 days during mountaineering<br>* Other names: Starch;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence measured by Lake Louise acute mountain sickness score (LLS) ≥ 3 with headache and one other symptom. | The LLS rates 5 symptoms (headache, gastrointestinal symptoms such as nausea and vomiting, fatigue and/or weakness, dizziness and/or light-headedness, and difficulty sleeping), with each item graded on a scale from 0 to 3. A score of 3 points or greater constitutes AMS. | within 18 hours after ascent to altitude 3100m | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood oxygen content | Blood oxygen content was measured by pulse oximetry (NPB 40, Nellcor, Pleasanton, CA, USA) within 1-2 hours after ascent to altitude 3100m. | on arrival of altitude 3100m | 
| severe AMS | Incidence measured by Lake Louise acute mountain sickness score (LLS) ≥ 5 with headache and one other symptom. | within 18 hours after ascent to altitude 3100m | 
| severity of headache, incidence of headache and severe headache | severe headache is determined by cut off between scores of 1 and 2 on the Lake Louise survey (ascending scale of 0-3 for severity) | Within 18 hours after ascent to altitude 3100m | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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acute mountain sickness, AMS, Rhodiola Crenulata, mountaineering, pulse oximetry, oxygen saturation