Astronauts Sunita Williams and Barry Wilmore will continue their stay at the International Space Station (ISS) until early 2025, NASA has confirmed. Initially a part of the Starliner's Crew Flight Test, they will now become full-time crew members. However, their extended stay poses health risks, including space anaemia, due to microgravity.
What is Space Anaemia?
A recent study published in Nature Medicine has shed light on the effects of space travel on the human body, specifically the phenomenon of space anaemia. Researchers found that astronauts experience a reduction in red blood cell mass during long-duration space flight, which can have long-term implications for their health.
The study, conducted by Trudel and colleagues, followed 14 astronauts on 6-month missions to the International Space Station and monitored their blood and exhaled air samples for signs of red blood cell destruction, known as hemolysis.
The results showed increased levels of carbon monoxide elimination and free haemoglobin in the blood, indicating hemolysis, which remained raised even a year after returning from space.
Causes
- Microgravity: In space, the body doesn't need to work as hard to maintain blood flow, leading to a decrease in RBC production.
- Hemolysis: The destruction of RBCs increases in space, leading to a reduction in overall RBC count.
- Fluid Shifts: Upon arrival in space, fluids shift towards the upper body, causing a temporary increase in blood volume. However, this effect wears off, and the body adapts by reducing RBC production.
Effects
- The body destroys red blood cells faster than it can produce them in space.
- This can cause fatigue, weakness, and reduced mental performance.
- Prolonged exposure can lead to bone loss, muscle atrophy, and cardiovascular, and vision changes.
Prevention
- Regular blood tests to monitor RBC count and haemoglobin levels.
- Ensuring adequate nutrition to support RBC production.
- Regular exercise to maintain muscle mass and cardiovascular health.
- Developing strategies to mitigate the effects of microgravity on RBC production.
Sunita Williams and Barry Wilmore will return to Earth via SpaceX Dragon, replacing the initially planned Boeing Starliner. As they prepare for their extended stay, NASA and the astronauts will closely monitor their health to mitigate the effects of microgravity.
