New details have been revealed regarding Catherine O'Hara's sudden death. O'Hara's immediate cause of death was listed as a pulmonary embolism, which is a blood clot in the lungs, with rectal cancer as the underlying cause, according to the Los Angeles County Medical Examiner's Office report obtained by TMZ on Monday, February 9. The report also noted that O'Hara has been cremated. Us Weekly confirmed on January 30 that the Schitt's Creek actress had died at the age of 71. Creative Artists Agency shared in a statement at the time that O'Hara died in L.A. following "a brief illness.