Neurovestibular symptoms following space flight.

Neurovestibular symptoms experienced by astronauts in the post-flight period were examined using data from medical debriefs contained in the NASA Longitudinal Study of Astronaut Health database. Ten symptoms were identified (clumsiness, difficulty concentrating, persisting sensation aftereffects, nausea, vomiting, vertigo while walking, vertigo while standing, difficulty walking a straight line, blurred vision, and dry heaves), of which eight were crossed with twelve demographic parameters (mission duration, astronaut gender, age, one-g piloting experience, previous space flight experience, g-suit inflation, g-suit deflation, in-flight space motion sickness, in-flight exercise, post-flight exercise, mission role, fluid loading). Three symptoms were experienced by a majority of subjects, and another two by more than a quarter of the subjects. Intensity of the symptoms was mild, suggesting that they are unlikely to pose a risk to the crew during landing and the post-flight period. Seven of the symptoms and eight of the parameters under study were found to be significantly associated with each other.