Astronaut medical records reveal the health toll of space travel

More light could be shed on how space flight affects astronauts’ health after the creation of the first “space-omics” biobank – a collection of thousands of blood and tissue samples, plus medical information, taken over multiple space missions.

These include missions to the International Space Station, as well as the first all-civilian space flight, SpaceX’s Inspiration4, which took four non-government-trained astronauts into space for three days in 2021.

Called the Space Omics and Medical Atlas (SOMA), the resource contains detailed medical data, such as on DNA damage and changes in people’s gene activity and immune system functioning, collectively known as biomarkers.

Space flight is known to pose certain health risks. For instance, astronauts lose bone density and muscle mass due to the lack of gravity, and higher levels of radiation in space seem to cause cell and DNA damage, which have a range of impacts on the body. These effects may be why astronauts are more prone to developing heart disease in later life and some have experienced worsening vision after being in space.

Collecting astronauts’ medical data in a consistent way via the SOMA biobank will help researchers understand more about these changes and potentially develop ways to mitigate them, says Christopher Mason at Weill Cornell Medicine in New York, who helped put the biobank together.

“Biomarkers don’t always translate into anything that’s clinically meaningful, but it’s a nice way to start to understand how this unique environment is impacting us,” says Damian Bailey at the University of South Wales in the UK, who wasn’t involved in the work.

One insight from the Inspiration4 mission is that, despite the astronauts experiencing a host of biomarker changes, most measurements returned to normal within a few months of them coming back to Earth.

This suggests that sending civilians into space doesn’t pose more health risks than sending professional astronauts, says Mason. “Instead of people training for decades to go, we could start to really open up space towards more and more people.”

The results from Inspiration4, which was crewed by two men and two women, also suggest that the changes in gene activity returned to normal faster in the women. That may be because women’s bodies have to be able to cope with a potential pregnancy, says Mason. “Being able to tolerate large changes in physiology and fluid dynamics may be great for being able to manage pregnancy, but also manage the stress of spaceflight.”

Timothy Etheridge at the University of Exeter in the UK says it will be helpful for researchers around the world to have a common resource they can use. “You need to have a consistent approach to collecting samples,” he says.

Thomas Smith at King’s College London says understanding the health impacts of space flight will become more important if longer missions happen, such as journeys to Mars. “Anything that leads to extended duration missions, it’s more important to know what’s going on and, ideally, address it,” he says.