A human mission to Mars: Predicting the bone mineral density loss of astronauts

Autoři: Eneko Axpe aff001;  Doreen Chan aff002;  Metadel F. Abegaz aff001;  Ann-Sofie Schreurs aff001;  Joshua S. Alwood aff001;  Ruth K. Globus aff001;  Eric A. Appel aff002
Působiště autorů: Space Biosciences Division, NASA-Ames Research Center, California, United States of America aff001;  Department of Materials Science & Engineering, Stanford University, Stanford, California, United States of America aff002;  Department of Chemistry, Stanford University, Stanford, California, United States of America aff003;  Department of Bioengineering, Stanford University, Stanford, California, United States of America aff004
Vyšlo v časopise: PLoS ONE 15(1)
Kategorie: Research Article
doi: 10.1371/journal.pone.0226434


A round-trip human mission to Mars is anticipated to last roughly three years. Spaceflight conditions are known to cause loss of bone mineral density (BMD) in astronauts, increasing bone fracture risk. There is an urgent need to understand BMD progression as a function of spaceflight time to minimize associated health implications and ensure mission success. Here we introduce a nonlinear mathematical model of BMD loss for candidate human missions to Mars: (i) Opposition class trajectory (400–600 days), and (ii) Conjunction class trajectory (1000–1200 days). Using femoral neck BMD data (N = 69) from astronauts after 132-day and 228-day spaceflight and the World Health Organization’s fracture risk recommendation, we predicted post-mission risk and associated osteopathology. Our model predicts 62% opposition class astronauts and 100% conjunction class astronauts will develop osteopenia, with 33% being at risk for osteoporosis. This model can help in implementing countermeasure strategies and inform space agencies’ choice of crew candidates.

Klíčová slova:

Bone density – Bone fracture – Mathematical models – Osteopenia and osteoporosis – Osteoporosis – Spaceflight – Mars – Astronauts


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