Space headache on Earth: Head-down-tilted bed rest studies simulating outer-space microgravity. (April 2015)

• Record Type: Journal Article
• Authors: van Oosterhout, WPJ; Terwindt, GM; Vein, AA; Ferrari, MD
• Is Part Of: Cephalalgia. Volume 35:Number 4(2015)
• Page Start: 335
• Page End: 343
• Publication Date: 2015-04
• Subjects: Space headache -- artificial microgravity -- head-down-tilted bed rest study -- countermeasures; Headache -- Periodicals; 616.8491
• DOI: 10.1177/0333102414536058
• Languages: English
• ISSNs: 0333-1024

Abstract

Background: Headache is a common symptom during space travel, both isolated and as part of space motion syndrome. Head-down-tilted bed rest (HDTBR) studies are used to simulate outer space microgravity on Earth, and allow countermeasure interventions such as artificial gravity and training protocols, aimed at restoring microgravity-induced physiological changes. Objectives: The objectives of this article are to assess headache incidence and characteristics during HDTBR, and to evaluate the effects of countermeasures. Methods: In a randomized cross-over design by the European Space Agency (ESA), 22 healthy male subjects, without primary headache history, underwent three periods of –6-degree HDTBR. In two of these episodes countermeasure protocols were added, with either centrifugation or aerobic exercise training protocols. Headache occurrence and characteristics were daily assessed using a specially designed questionnaire. Results: In total 14/22 (63.6%) subjects reported a headache during ≥1 of the three HDTBR periods, in 12/14 (85.7%) non-specific, and two of 14 (14.4%) migraine. The occurrence of headache did not differ between HDTBR with and without countermeasures: 12/22 (54.5%) subjects vs. eight of 22 (36.4%) subjects; p = 0.20; 13/109 (11.9%) headache days vs. 36/213 (16.9%) headache days; p = 0.24). During countermeasures headaches were, however, more often mild ( p = 0.03) and had fewer associated symptoms ( p = 0.008). Conclusions: Simulated microgravity during HDTBR induces headache episodes, mostly on the first day. Countermeasures are useful in reducing headache severity and associated symptoms. Reversible, microgravity-induced cephalic fluid shift may cause headache, also on Earth. HDTBR can be used to study space headache on Earth.