O.E. wyrgan "to strangle," from W.Gmc. *wurgijanan (cf. M.Du. worghen, Du. worgen, O.H.G. wurgen, Ger. würgen "to strangle," O.N. virgill "rope"), from PIE *wergh- "to turn" (see wring). The oldest sense was obs. in Eng. after c.1600; meaning "annoy, bother, vex," first recorded 1671, developed from that of "harass by rough or severe treatment" (1553), as of dogs or wolves attacking sheep. Meaning "to cause mental distress or trouble" is attested from 1822; intrans. sense of "to feel anxiety or mental trouble" is first recorded 1860.
1804, from worry (v.). Worrisome is first recorded 1845. Worry wart first recorded 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 colloq. meaning.