Year: 2009 Source: American Journal of Psychiatry, v.166, no.10, (October 2009), p.1124-1134 SIEC No: 20100798

A family study of suicide was conducted by examining 3 proband groups: probands who died by suicide in the context of major depressive disorder; living depressed probands with no history of suicidal behaviours; & psychiatrically normal community comparison probands. The relatives of probands who died by suicide had higher levels of suicidal behaviour than the relatives of nonsuicidal depressed probands & community comparison probands. Testing cluster B traits as intermediate phenotypes of suicide showed that the relatives of depressed probands who died by suicide had elevated levels of cluster B traits. Familial predisposition to suicide was associated with increased levels of cluster B traits. Cluster B traits mediated, at least in part, the relationship between familial predisposition & suicide attempts among relatives. (58 refs.) JA