Astronauts of the US National Aeronautics and Space Administration (NASA): cohort profile

Occupational cohorts are important to understanding the unique exposures of a workforce. The individuals selected by the National Aeronautics and Space Administration (NASA) to be astronauts experience occupational exposures unlike any other. To better understand the short- and long-term health effects of spaceflight, health and exposure data are collected on this cohort through clinical and other surveillance settings.

This cohort is composed of the 360 astronauts who have been selected by NASA from the first selection class in 1959 to the most recent class of 2022. Selection of crewmembers is based on specific skills, education, military experience and fitness for flight. Due to the stringent and specific selection criteria, this occupational cohort encompasses a population that is more homogeneous than other groups. However, with the evolution of selection criteria along with changes to health screening and data collection processes, each selection class has a varying baseline health status.

Data on a variety of health outcomes and risk factors have been collected along with occupational, physiological and exposure data, demographic and socioeconomic information and exposures that occurred prior to selection. Data have been used for both research activities, such as studies addressing Spaceflight Associated Neuro-ocular Syndrome and venous thromboembolism, and occupational surveillance activities like monitoring cardiovascular health preflight, in-flight and postflight. Characterisation of these factors helps not only with current monitoring but also informs future risk reduction decisions for exploration missions.

As NASA plans missions to the Moon and Mars, the evidence base for this cohort will continue to grow through annual and mission-related data collection of current, future and retired crewmembers. Data for this cohort will continue to be collected as long as NASA continues to fly humans in space. As more data is collected, future research and surveillance activities will continue to be developed both internally and externally. One area that we aim to use this cohort is to compare with other cohorts to measure the risk of astronaut training and spaceflight, as some previous studies have done in the past.