Hoenemann J-N, Moestl S, Diedrich A, Mulder E, Frett T, Petrat G, Pustowalow W, Arz M, Schmitz M-T, Heusser K, Lee S M C, Jordan J, Tank J, Hoffmann F
Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany.
Department of Internal Medicine III, Division of Cardiology, Pneumology, Angiology, and Intensive Care, University of Cologne, Cologne, Germany.
Front Cardiovasc Med. 2023 Oct 23;10:1250727. doi: 10.3389/fcvm.2023.1250727. eCollection 2023.
Impaired cardiovascular autonomic control following space flight or immobilization may limit the ability to cope with additional hemodynamic stimuli. Head-down tilt bedrest is an established terrestrial analog for space flight and offers the opportunity to test potential countermeasures for autonomic cardiovascular deconditioning. Previous studies revealed a possible benefit of daily artificial gravity on cardiovascular autonomic control following head-down tilt bedrest, but there is a need for efficiency in a long-term study before an artificial gravity facility would be brought to space. We hypothesized that artificial gravity through short-arm centrifugation attenuates functional adaptions of autonomic function during head-down tilt bed rest. 24 healthy persons (8 women, 33.4 ± 9.3 years, 24.3 ± 2.1 kg/m) participated in the 60-day head-down tilt bed rest (AGBRESA) study. They were assigned to three groups, 30 min/day continuous, or 6(5 min intermittent short-arm centrifugation, or a control group. We assessed autonomic cardiovascular control in the supine position and in 5 minutes 80° head-up tilt position before and immediately after bed rest. We computed heart rate variability (HRV) in the time (rmssd) and frequency domain, blood pressure variability, and baroreflex sensitivity (BRS). RR interval corrected rmssd was reduced supine ( = 0.0358) and during HUT ( = 0.0161). Heart rate variability in the high-frequency band (hf-RRI; = 0.0004) and BRS ( < 0.0001) decreased, whereas blood pressure variability in the low-frequency band (lf-SBP, = 0.0008) increased following bedrest in all groups. We did not detect significant interactions between bedrest and interventions. We conclude that up to daily 30 min of artificial gravity on a short-arm centrifuge with 1Gz at the center of mass do not suffice to prevent changes in autonomic cardiovascular control following 60-day of 6° head-down tilt bed rest. : https://drks.de/search/en/trial/DRKS00015677, identifier, DRKS00015677.
太空飞行或长期卧床后心血管自主神经控制受损，可能会限制应对额外血流动力学刺激的能力。头低位卧床休息是一种公认的太空飞行地面模拟方式，为测试自主神经心血管失适应的潜在对策提供了机会。先前的研究显示，每日人工重力对头低位卧床休息后的心血管自主神经控制可能有益，但在将人工重力设施送入太空之前，需要进行长期高效的研究。我们假设，通过短臂离心产生的人工重力可减弱头低位卧床休息期间自主神经功能的适应性变化。24名健康受试者（8名女性，年龄33.4±9.3岁，体重指数24.3±2.1kg/m²）参与了为期60天的头低位卧床休息（AGBRESA）研究。他们被分为三组，分别接受每天30分钟的持续人工重力、每天6次（每次5分钟）的间歇性短臂离心，或作为对照组。我们在卧床休息前后分别评估了仰卧位和5分钟80°头高位倾斜位时的自主神经心血管控制情况。我们计算了时域（rmssd）和频域的心率变异性（HRV）、血压变异性以及压力反射敏感性（BRS）。所有组在卧床休息后，仰卧位时RR间期校正后的rmssd降低（P = 0.0358），头高位倾斜位时降低（P = 0.0161）。高频带心率变异性（hf - RRI；P = 0.0ooo4）和BRS（P < 0.0001）降低，而所有组卧床休息后低频带血压变异性（lf - SBP，P = 0.0008）升高。我们未检测到卧床休息与干预措施之间的显著交互作用。我们得出结论，在质心处1Gz的短臂离心机上每天施加长达30分钟的人工重力，不足以预防6°头低位卧床休息60天后自主神经心血管控制的变化。: https://drks.de/search/en/trial/DRKS00015677，标识符，DRKS00015677 。
