Three New Ideas to Protect Special Forces From the Stress of High Altitude

University of Colorado Denver (CU Denver)

Status and phase: Completed; Phase 4

Conditions: Mountain Sickness

Treatments: Drug: Nifedipine extended release; Drug: Placebo; Dietary Supplement: Quercetin; Drug: Nitrite; Drug: Methazolamide; Drug: Metformin

Study type: Interventional

Funder types: Other

Identifiers

NCT02463357

15-0254

Details and patient eligibility

About

Acute Mountain Sickness (AMS) is a well-documented syndrome that affects 42% of non-acclimatized individuals traveling to altitudes above 10,000 feet. Decreased barometric pressure, which leads to low blood oxygen levels, is the primary casual factor of AMS. Symptoms of AMS are characterized by headache, nausea, vomiting, dizziness, fatigue and difficultly sleeping. Moreover, when people travel to high altitude, cognitive performance and endurance exercise capacity are impaired. Therefore, the goal of this research is to identify effective pharmacological agents that will help reduce the symptoms of AMS and improve physical and cognitive performance at high altitude.

The investigators will study the efficacy of the dietary supplement, quercetin, the drugs nifedipine (extended release) and methazolamide taken together, the drug metformin, and the drug nitrite in reducing symptoms of AMS and improving cognitive and exercise performance at high altitudes.

Enrollment: 148 patients

Sex: Male

Ages: 18 to 30 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• healthy,
• young (18-30 years old) men who can meet APFT requirements for special operation forces (SOF) training as outlined by the US Army (42 push ups, 53 sit-ups, 6 pull-ups, 2 mile run in < 15 min 54 s)

Exclusion criteria

• women;
• smokers;
• participants with diseases or disorders known to be affected by hypoxia or the drugs used in this study, such as hypotension, anemia, sickle cell trait or disease, and diabetes;
• participants with a history of significant head injury, migraines or seizures;
• participants taking any medication (over-the-counter or prescription) or herbal supplements;
• participants with known flavonoid allergies;
• participants with known allergies to metformin;
• participants with known hypersensitivity reaction to nifedipine;
• participants with known allergies to sulfonamide-based drugs;
• participants with inability to be headache-free when consuming the amount of caffeine in two six ounce cups of coffee or less per day;
• exposure to high altitude above 1000m in the previous three months; or
• participants who have been on an airline flight over six hours (the lowered cabin pressure for an extended period of time approximates exposure to high altitude);
• participants who are unable to achieve the minimum physical criteria required for SOF training

Trial design

Primary purpose: Prevention

Allocation: Non-Randomized

Interventional model: Factorial Assignment

Masking: Triple Blind

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148 participants in 5 patient groups, including a placebo group

Quercetin

Experimental group

Description:

Quercetin: 500mg pill, twice daily for 5 days

Treatment:

Dietary Supplement: Quercetin

Nifedipine+Methazolamide

Experimental group

Description:

Nifedipine extended release: 30mg pill, twice daily for 5 days; Methazolamide: 125mg pill, twice daily for 5 days

Treatment:

Drug: Nifedipine extended release

Drug: Methazolamide

Metformin

Experimental group

Description:

Metformin: 500mg pill, once daily for 2 days, then 500mg twice daily at altitude (3 days)

Treatment:

Drug: Metformin

Placebo

Placebo Comparator group

Description:

Sugar pill manufactured to look like all other investigational products

Treatment:

Drug: Placebo

Nitrite

Experimental group

Description:

Nitrite: 20mg pill, three times daily for 5 days

Treatment:

Drug: Nitrite