Military Funds Altitude Sickness Study In Colorado

DENVER (AP) - The University of Colorado medical school is trying to develop a simple test to identify soldiers who might be vulnerable to the debilitating headaches, nausea and fatigue of altitude sickness in mountainous combat zones such as Afghanistan.

The school is also studying the mechanisms that help human cells adjust to high altitude, which eventually could lead to medications that mimic that process, allowing people to acclimate to high altitude faster.

The Defense Department awarded the medical school's Altitude Research Center two grants totaling $4 million for both research projects, Robert Roach, director of the center, said Monday.

"An ideal goal down the road would be to develop a pill that mimics the process of acclimation," Roach said. "The best way to avoid mountain sickness is to be acclimatized."

A spokeswoman for the Army Telemedicine and Advanced Technology Research Center, the office that awarded the grants, didn't immediately return a call seeking comment.

Altitude sickness is caused by a lack of oxygen. At 18,000 feet above sea level, each breath gathers half as much oxygen as it does at sea level, Roach said. Symptoms, which can range from minor to severe, can also include excessive thirst, sleeplessness and even swelling of the brain.

An earlier study by the Altitude Research Center found a way to predict with better than 90 percent accuracy whether someone would develop altitude sickness, Roach said.

In that study, researchers did blood tests on 28 subjects from the Denver area -- about 5,280 feet above sea level -- before they spent 10 hours in a hypobaric chamber that simulated the effects of being at 16,000 feet. The tests found that if a certain set of genes was switched on or off in a specific combination, the subjects usually suffered altitude sickness from being in the chamber, Roach said.

The first phase of the Defense Department-funded study, which will take place this summer, will look for the same genetic marker or others in a larger study group under different conditions. About 140 people from the Dallas area, which is about 460 feet above sea level, will be given blood tests before spending 2 1/2 days in the Colorado resort town of Breckenridge, elevation 9,600, to see if they develop altitude sickness.

Their stay will include a hike to the top of an 11,650-foot mountain.

In Afghanistan, the elevation can range up to more than 24,000 feet, according to the CIA's World Factbook.

It will take about nine months to analyze the data, Roach said.

The second phase, in the summer of 2012, will study 24 research subjects who will spend about three weeks at 17,000 feet elevation in Bolivia. That phase will look for the cellular mechanisms that help the human body adjust to altitude, Roach said.

"We know the macro-processes. We know you breathe more, the heart beats faster," Roach said. "We don't know the micro-processes that control all those processes."

The military has used Colorado as a laboratory and training ground for high-altitude warfare since at least World War II, when the 10th Mountain Division trained at Camp Hale west of Breckenridge. Army helicopter pilots regularly practice flying in the Colorado mountains.

- By Dan Elliott, AP Writer

(Copyright 2011 by The Associated Press.  All Rights Reserved.)