Figure 1. The proportional mortality rate due to cardiovascular disease in the United States among individuals age 55–64 years, non-flight astronauts, astronauts that flew only low Earth orbit missions, all flight astronauts, and Apollo astronauts that flew missions to the Moon.

*Significantly different from the US population 55–64 years of age at the time of death, P ≤ 0.05. ^†Significantly different from the non-flight astronaut group, P ≤ 0.05. ^‡Significantly different from the low Earth orbit astronaut group, P ≤ 0.1.