Relationships between premorbid personalities and unipolar depressions.

One hundred and fifty consecutive patients with unipolar psychotic ("endogenous") depression were investigated to illuminate any relationships existing between premorbid personality traits and the development of depressive illness. In some cases personality and psychological stress appeared to combine to produce depression, while in others physical stresses appeared to be the principal etiological agents, and to operate in the absence of personality and psychological factors. The contribution of these different factors to causation are discussed and explored.