There's a similar topic on another forum, and this is what I posted there:
I'm actually writing a research paper for a psychology class now and in my review of past research I've found some studies on correlations between mental illness and MBTI. All of these studies were published in professional, peer-reviewed journals:
*A 1994 found that those most at risk for suicidal ideation and behaviors are IxxP females, ISFx males, INxP males, and ENxJ males (BTW, their hypothesis was that INFPs would be most at risk for suicide)
*A 1996 study found that depressed patients were more comonly ISxPs, biploar patients were more commonly INxPs, and social phobia patients were usually IxxJ
*A 1997 study found that ITs are overly rigid, ISs are obsessive, and IFs are depressive
*A 1999 study found that bipolar patients are signficantly more extroverted and less judging than unipolar depressed patients (I've also seen a bunch of studies using the Big Five Personality Model that also found bipolar patients are more extroverted than depressed patients)
*A 2002 study found that depression patients were significantly more introverted, sensing, feeling, and perceiving; the overrepresented types are ISFPs and INFPs; and male ISFPs in particular are the most overrepresented in depression