Sleep-wake differences in cardiac autonomic activity during a 105-day simulated mission to mars

DANIEL E. VIGO; BARBARA OGRINZ; LI WAN; EVGENY BERSENEV; FRANCIS TUERLINCKX; OMER VAN DEN BERGH; ANDRÉ E. AUBERT

Moscú

Congreso; Space-Forum 2011; 2011

INSTITUTE OF BIOMEDICAL PROBLEMS, RUSSIAN ACADEMY OF SCIENCES

Introduction: Long-term space flight is characterized by microgravity and confinement, and both of them are likely to play a role in alterations of autonomic cardiovascular control. Our objective was to investigate whether the sleep-wake variations in the autonomic control of the heart are altered by long-term confinement during the 105-day pilot study of the Mars500 project, currently ongoing. Methods: Twenty-four-hour EKG records were obtained before,during (30, 70 and 100 days), and after confinement in the six crew members that participated in the mission. Sleep and wake periods were determined by fitting a square wave to the data. Autonomic activity was evaluated through time and frequency domain indexes of heart rate variability analysis in wake and sleep periods. Results: During confinement, wake heart rate variability showed decreased mean heart rate and increased amplitude in the very low (p