Stories We Like: Novels For Language Lovers
1956, from comic strip "Out Our Way" by U.S. cartoonist J.R. Williams (1888-1957). According to those familiar with the strip, Worry Wart was the name of a character who caused others to worry, which is the inverse of the current colloquial meaning.
A person who worries excessively; a constantly apprehensive person
[1956+; fr the designation of such a person in the comic strip ''Out Our Way'' by J R Williams]