Learning about medical risks of spaceflight through LSAH

Performing an Optical Coherence Tomography (OCT) imaging test to look in-depth for any changes in my retinas

Last week, I was in Houston, Texas for medical testing. Every year, usually around my birth date, I return to the NASA Johnson Space Center to participate in the Lifetime Surveillance of Astronaut Health program. The Canadian Space Agency supports my participation.

Lifetime Surveillance of Astronaut Health (LSAH) is a proactive medical surveillance program. Its purpose is to monitor astronauts for occupationally-related disease.

My participation in the program began with my selection as an astronaut many years ago, and then continued throughout my spaceflights and now into retirement. My career exposed me to unique spaceflight environments (e.g. weightlessness, ionizing radiation, loud ambient noise levels, circadian dysrhythmias, isolation and confinement) and training situations (e.g. work in pressure suits and aboard high performance aircraft) that could result in eventual health problems. The LSAH program is designed to detect any of these problems at an early stage and to take action to prevent their progression.

The program also has a clinical research component. Astronaut medical data are analyzed by interdisciplinary teams to determine risks and health trends. For instance, one LSAH team has researched EVA-associated shoulder injury. Another evaluated the relationship between inflight reports of headaches and cabin CO₂ levels aboard the International Space Station. A microbiology team determined whether opportunistic microorganisms found aboard the ISS are associated with infections, rashes, or gastrointestinal problems. And epidemiologists are assessing whether morbidity and mortality due to cancer are different amongst the astronaut corps compared to the general population. The results of these kinds of studies help us to develop preventive measures and clinical practice guidelines.

My medical evaluation at NASA-JSC consisted of a history and physical exam by a flight surgeon as well as several laboratory tests. My bone density is evaluated by DXA scan every three years. And I sometimes undergo additional screening exams tailored to my particular medical and exposure history. The medical testing is rigorous and will continue throughout my lifetime. I am pleased to participate. We are learning more about the medical effects and risks of training and spaceflight and are developing countermeasures to protect future astronauts against adverse exposures and illness.

Blood tubes lined up and ready to get personal with my arm

I only regret that my birth month is August when Houston heat and humidity are at their worst! I can think of other places to be at this time of the summer.

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