Numerous ways in which a microgravity environment and other elements can interfere with the human body during space missions have been found by research in the rapidly developing subject of space medicine.
The field has benefited from a recent study that has revealed a previously unknown increase in headache frequency among astronauts.
24 astronauts from the United States, Europe, and Japan who spent up to 26 weeks on the International Space Station participated in the study. All but two of them claimed to have had headaches while in space.
Based on earlier anecdotal information, the researchers had anticipated a lower percentage than this one.
The headaches happened not only during the first several weeks in space as the body adjusts to microgravity, but also thereafter. Some of the headaches resembled migraines, while others resembled tension headaches.
According to the study, headaches that occur early in space flight tend to exhibit as migraine-type headaches, whereas headaches that occur later in space travel present more like tension headaches.
Lead author of the study published this week in the journal Neurology, neurologist WPJ van Oosterhout of Zaans Medical Center and the Leiden University Medical Center in the Netherlands, said, “We hypothesize that different mechanisms are involved for the early headache episodes – the first one to two weeks in space – versus later headache episodes.”
“Space adaption syndrome is the term for the first week when the body adjusts to the absence of gravity. Similar to motion sickness, this phenomena can result in headaches, nausea, vomiting, and dizziness, according to Van Oosterhout.
The headaches that followed might be caused by elevated intracranial pressure. Microgravity causes more fluid to accumulate in the brain and upper body, which raises the pressure inside the skull.”
According to Van Oosterhout, migraines on Earth typically cause throbbing, pulsating headaches that last four to seven hours. They can also cause nausea, vomiting, and light and sound sensitivity.
According to Van Oosterhout, tension-type headaches on Earth typically cause a dull discomfort that spreads across the entire head in the absence of other symptoms.
23 of the 24 astronauts, who had an average age of roughly 47, were men and one woman who served on the International Space Station from November 2011 to June 2018. During their 3,596 days in orbit, 22 of the astronauts had 378 headaches.
Three months after returning to Earth, not one of the twenty-four reported having a headache.
NASA accounted for thirteen astronauts, the European Space Agency for six, Japan’s JAXA for two, and the Canadian Space Agency for one.
Space flight has been linked to a number of known side effects, such as immune system, brain, and cardiovascular system alterations, atrophy of the bones and muscles, inner ear balance problems, and eye syndromes.
Another worry is the increased danger of cancer from radiation exposure in space.
The extent to which these impacts could be a hindrance to long-duration human space travel—such as trips to Mars or other nearby planets—is unknown to experts.
“The honest answer is that we don’t know the effects of long-duration space travel – possibly years – on the human body,” Van Oosterhout stated.
It is evident that even brief exposure to microgravity—days or weeks—to medium-term exposure—weeks or months—has various effects, most of which are reversible,
