Former Senate majority leader Bill Frist and his wife of 31 years, Karyn, have divorced.

Family spokeswoman says the Frists "ask for prayers, understanding and privacy at this time."

Frist was a heart surgeon before entering politics in 1994. He spent 12 years in the Senate.

He was widely expected to make a 2008 presidential bid, but cited his close ties with the unpopular Bush administration in his decision not to run.