There was a piece on Chris Benoit and the severe concussions he had and the impact it may have had on him going beserk and killing his wife, children and himself. The report also investigated football concussions and their impact in the untimely deaths of ex-pro football players. The tragic lives of three ex-Eskimos who died young were examined.
Premature to say that is what happened here and hopefully it will turn out that McNair and the woman died at someone else's hand, but McNair did have a history of concussions.
Fifth Estate report here:
http://www.cbc.ca/fifth/fighttothedeath/