> Across 89 shuttle missions from 1981 to 1998, US astronauts had over 1,800 in-flight medical events; less than 2 percent of these were related to behavioral health, largely stemming from “anxiety and annoyance.”

https://en.wikipedia.org/wiki/Psychological_and_sociological... doesn't mention much that sounds significant (and they're likely the same sort of things that happen on, say, a nuclear submarine).

Any particular Google results you want to steer me towards?