"Tangential" bipolar disorder?

Q: The neighbor across the street has a sister that has been dx. with a tangential bipolar disorder, what is this and how does it differ from the regular bipolar disorders?

Dear Ms. G' --
No such thing in our formal "diagnostic" lingo.  There are many bipolar variations and this may be an informal term some doctor used to specify a high degree of "tangential" (erratic, only partly related) thinking.

Dr. Phelps

Published February, 2001