Astronauts who flew into deep space on Apollo lunar missions were more likely to die from a cardiovascular problem than astronauts who didn’t venture beyond the Earth’s orbit, according to a new study.
The study by Florida State University and NASA researchers compared the causes of death for seven Apollo astronauts and 70 others who did not travel beyond the Earth’s protective magnetic field.
The study found that 43 per cent of deceased Apollo astronauts died from a cardiovascular problem. That’s four to five times higher than cardiovascular-related deaths among astronauts who only flew in low Earth orbit or never flew at all.
Although the sample size is small, the study suggests that exposure to deep space radiation could be linked to increased heart disease risks.
Michael Delp, the lead author of the study and Florida State University’s dean of human sciences, told the FSU news site that the deep space Apollo astronauts were exposed to levels of galactic cosmic radiation that have not been experienced by any other space travellers.
Little is understood about the effects of cosmic radiation on the cardiovascular system and this study provides a first glimpse, Delp said.
Delp and his colleagues also exposed mice to the same type of radiation, while simulating weightlessness. After six months, the researchers noted “sustained vascular endothelial cell dysfunction” in the mice, an impairment that is known to result in artery disease. The weightlessness did not appear to have an effect on the mice, but the radiation did.
The researchers say this study is an important step in understanding the impact of space exploration on astronauts’ health.
