ISLAMABAD, Jan 20 (APP): Astronauts can develop space anemia because their bodies destroy more red blood cells than normal when in space, reveals a research study.
Dr. Guy Trudel, a rehabilitation physician and researcher at The Ottawa Hospital and professor of Medicine at the University of Ottawa, and his team published the results of a five-year study that reveals how space travel causes lower red blood cell counts, known as space anemia.
At the International Space Station, study of 14 astronauts (11 men and 3 women) funded by the Canadian Space Agency(CSA) found that 54% more blood cells were destroyed while they were in space than when they were on earth, according to the findings published in Nature Medicine.
“Space anemia has consistently been reported when astronauts returned to earth since the first space missions, but we didn’t know why,” said Dr. Guy Trudel. “Our study shows that upon arriving in space, more red blood cells are destroyed, and this continues for the entire duration of the astronauts’ mission.” he informed.
Until now it was thought to be temporary as one NASA study called it “a 15-day ailment.” Doctors attributed it to destruction of red blood cells, or hemolysis, resulting from fluid shifts as astronauts’ bodies accommodated to weightlessness and again as they re-accommodated to gravity.
In fact, anemia is “a primary effect of going to space,” said Dr. Guy adding that “as long as you are in space, you are destroying more blood cells than you are making.”
Normally, the body destroys and replaces nearly 2 million red blood cells per second. Trudel’s team found astronauts’ bodies destroyed 3 million red blood cells per second during their six-month missions.
The astronauts generated extra red cells to compensate for the destroyed ones. But, Trudel asked, how long can the body constantly produce 50% more red cells? A round trip mission to Mars would take about two years, NASA estimated.
“If you are on your way to Mars and you can’t keep up with the need to produce all those extra red blood cells, you could be in serious trouble,” Trudel said.
“Thankfully, having fewer red blood cells in space isn’t a problem when your body is weightless but when landing on Earth and potentially on other planets or moons, anemia affecting your energy, endurance, and strength can threaten mission objectives. The effects of anemia are only felt once you land, and must deal with gravity again.”
A year after returning to Earth, the astronauts’ red blood cells had not completely returned to pre-flight levels, his team reported in Nature Medicine. In this study, five out of 13 astronauts were clinically anemic when they landed —one of the 14 astronauts did not have blood drawn on landing.
Sulekha Anand, who researches human physiology at San Jose State University and was not involved in the study, agreed that “the findings have implications for understanding the physiological consequences of space flight and anemia in patients on the ground”.
“These findings are spectacular, considering these measurements had never been made before and we had no idea if we were going to find anything. We were surprised and rewarded for our curiosity. If we can find out exactly what’s causing this red blood cell destruction, then there is a potential to treat it or prevent it, both for astronauts and for patients here on Earth,” Dr. Guy concluded.
