Space is truly a magical place, enchanting philosophers, scientists, artists and dreamers. From ancient civilizations that found pantheons of gods among the stars, to novelist Andy Weir’s visionary tale of human efforts to colonize Mars recently portrayed in the movie “The Martian,” to George Lucas’ epic drama between Jedis and Sith lords in “Star Wars,” it is clear that space draws humanity to push the frontiers of science and technology – or maybe just draws us to the box office.
Nonetheless, in this day and age there are astronauts and cosmonauts who have colonized lower earth orbit (LEO) on the International Space Station (ISS), in a situation quite similar to that of the station Arthur C. Clark envisioned in his 1968 science fiction novel, “2001: A Space Odyssey.”
Unfortunately, human physiology, which has evolved in and grown accustomed to Earth’s gravity, is completely altered in space where there is either no gravity effect or different gravitational pulls result from different planetary bodies. Because of this unique medical anomaly, the ISS is a platform for research of interest to a forward-thinking vascular specialist.
Dr. Richard Hughson, from the University of Waterloo in Waterloo, Ontario, is researching vascular aging in spaceflight crew members. His work is a part of the Schlegel-University of Waterloo Research Institute for Aging, where he is theme leader/chair of vascular aging and brain health and holds the Schlegel Research Chair in that discipline.
Dr. Hughson is supported by the Canadian Space Agency (CSA) and Canadian Institute for Health Research (CIHR) He discussed his research in a recent audio interview (http://cihr-irsc.gc.ca/e/49523.html).
Observations have demonstrated that short-duration and extended spaceflight missions may simulate accelerated vascular aging in some of these highly fit individuals traveling to space. Specifically, spaceflight crew members have been shown to have difficulty controlling a rise in their blood pressure, perhaps secondary to the loss of Earth’s gravity, but rather in the inherent cephalad fluid shift (as blood no longer pools in the legs). In addition, significant postflight postural hypotension and physical deconditioning with resultant sarcopenia and osteopenia are known to occur.
Dr. Hughson has shown through ultrasonography that the carotid arteries of spaceflight crew members are considerably stiffer compared to their preflight arteries and that they appear to have “aged the equivalent of 20-30 years in stiffness.” The ramifications of this type of research on the study of the normal earthbound vascular aging processes are under investigation.
To counteract the effects of vascular aging and physical deconditioning in space, physical activity is key; however, the 30 minutes per day allotted to busy astronauts amid their responsibilities is just not cutting it, according to Dr. Hughson. Missions are being extended for longer periods of time, leading to serious physical consequences, For example, American astronaut Scott Kelly’s year in space will certainly result in considerable accelerated aging in his arterial system. Thus, it becomes increasingly necessary to understand and prevent the vascular aging process in astronauts, future spaceflight crew members, and perhaps one day those seeking to colonize the Moon, Mars, and beyond.
When colonization time arrives, space agencies certainly should be in the market for well-qualified vascular specialists.
Perhaps great job opportunities await those in our profession who will be brave enough to leave Earth’s cradle.
Dr Drudi is a vascular surgery resident at McGill University, Montreal.