From the Grey Lady:
You probably think rabid sports fans are a bunch of lonely, disoriented souls who try to fill the holes in their lives by attaching themselves to a team. And you’re probably wrong.
A growing body of scientific research and some compelling empirical evidence suggest that sports fans, even the foam-at-the-mouth variety, are less prone to depression and alienation than people who are immune to such maladies as March Madness and pennant fever.
Assuming the science continues to be replicated and confirmed, this looks like something that has the potential to be interesting, assuming causality can be established. My bet is that causality runs from personality to sports, not the other way around (i.e. people who are less prone to depression are more likely to be sports fans). If, however, causality runs from sports to personality, it seems like there is the possibility to use sports as a form of psychotherapy. I guess we’ll have to see where the research leads.