Feasibility and Neurobehavioral Changes of 10-Day Simulated Microgravity in Acute Ischemic Stroke Patients

Abstract

Objective: The aim of the study was to investigate feasibility and functional changes of simulated microgravity with 6-degree head-down-tilt (HDT) bed rest in acute ischemic stroke.

Design: Patients without lesions in the cingulate cortex and/or cerebellum were enrolled. They underwent HDT for 30 minutes twice per day for 10 weekdays. Systolic blood pressure, diastolic blood pressure, and heart rate were measured before the HDT, immediately after, and also 30 minutes after the stop. Mini-Mental State Examination, Geriatric Depression Scale, Neurobehavioral Tests (i.e., span test, finger-tapping test, continuous performance test, and trail-making test) were conducted before and after the 10-day HDT.

Results: One male and four female patients (median age = 64.6 yrs [SD = 10.5 yrs]) were recruited. Changes in the finger-tapping test (57.80 [SD = 40.96 ] vs. 85.80 [SD = 0.46], P = 0.08) and in the digit span backward test (3.60 [SD = 1.14] vs. 1.42 [SD = 1.75], P = 0.07) were noticed. Few changes were found in other scales. No significant changes in systolic blood pressure, diastolic blood pressure, or heart rate were observed, and no adverse effects occurred.

Conclusions: The 6-degree HDT revealed no adverse effects on the cardiovascular system, showing nonsignificant increment in the finger-tapping test (representative of motor speed and performance) and nonsignificant reduction in the digit backward span test (representative of spatial memory).