Astronauts Suffer Frequent Headaches in Space

Introduction

Astronauts who embark on long-duration space missions face a unique set of challenges, one of which is the experience of persistent and debilitating headaches. These "space headaches" can significantly impact an astronaut's well-being and performance, making it crucial to understand their underlying causes and develop effective management strategies.

Studying Space Headaches

A team of researchers set out to investigate the incidence, timing, clinical features, and treatment of headaches experienced by astronauts during long-duration space flights. They evaluated a cohort of 24 astronauts from the European Space Agency (ESA), NASA, and the Japan Aerospace Exploration Agency (JAXA) who were assigned to International Space Station (ISS) expeditions between 2011 and 2018.

The researchers also analyzed retrospective data from an additional 42 astronauts to confirm their findings. By studying headaches in otherwise healthy individuals in the unique environment of space, the researchers aimed to enhance our understanding of headache disorders, such as migraine, on Earth.

Prevalence and Characteristics of Space Headaches

The study revealed that headaches were remarkably common among astronauts during their space missions. A staggering 91.7% of the 24 astronauts in the prospective study reported experiencing at least one episode of headache during their time in space, with a total of 378 headache episodes recorded.

In contrast, only 37.5% of the same group of astronauts reported experiencing headaches before their missions. This stark difference highlights the significant impact that the space environment can have on the development of headaches.

The researchers found that the majority of the headache episodes (89.9%) were classified as

s or probable tension-type headaches. However, a notable 10.1% of the headaches exhibited

migrainous

Referring to the characteristics or symptoms of a migraine, a type of severe headache that can cause additional symptoms like nausea, sensitivity to light, and visual disturbances.

 

features, particularly during the first week of the flight for astronauts without a prior history of recurrent headaches.

Headache Characteristics Over Time

The study revealed that the characteristics of the headaches experienced by astronauts changed over the course of their missions. During the first week of spaceflight, the headaches tended to have a migraine-like

, with associated symptoms such as nausea, vomiting, facial edema, and nasal congestion.

However, in the later weeks of the missions, the headaches more often resembled a tension-type headache (TTH) phenotype, with fewer accompanying symptoms. Interestingly, the occurrence and duration of the headache episodes decreased over time during the space flights, and no astronauts reported any headaches after returning to Earth.

Environmental Factors and Headache Occurrence

The researchers analyzed various environmental factors within the ISS, including levels of carbon dioxide, oxygen, temperature, and humidity, to determine if they were associated with the occurrence of headaches. Surprisingly, they found no correlation between the headache episodes and these ambient parameters.

This suggests that the underlying causes of the space headaches are not directly related to the physical environment of the space station, but rather may be linked to the physiological and neurological adaptations that astronauts experience in the

environment.

Treating Space Headaches

Astronauts employed a variety of strategies to manage their headaches during spaceflight. Acute anti-headache medications, especially non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen, were frequently used and reported to be effective.

In addition to medication, astronauts also found relief through other measures, such as sleeping, hydration, and caffeine intake. The researchers noted that the different treatment methods, including both medications and alternative approaches, were similarly effective in reducing the severity of the headache episodes.

Implications and Future Research

The study's findings suggest that headache is the most common symptom of

, particularly during the first week of spaceflight. This is likely due to the

cephalad

Referring to the upper part of the body, or the head and neck area. In the context of spaceflight, this means a shift of body fluids towards the head due to the lack of gravity.

 

(upward) redistribution of body fluids and the resulting increase in

intracranial pressure

The pressure inside the skull, which can increase in the microgravity environment of space and potentially cause headaches and other issues.

 

caused by the microgravity environment.

After the initial adaptation period, the headaches tend to resemble milder forms of

-related headaches observed on Earth, with tension-type headache being the predominant symptom.

The researchers emphasize the need for further research to better understand the underlying mechanisms of space headache and develop more effective therapies. Addressing this issue is crucial for ensuring the well-being and performance of space travelers, as headaches can significantly impact an astronaut's ability to carry out their duties during long-duration missions.

By studying space headaches, the researchers hope to gain valuable insights that can enhance our understanding of headache disorders, such as migraine, on Earth. The unique environment of space provides a natural laboratory for investigating the complex interplay between physiological, neurological, and environmental factors that contribute to the development of headaches.