Which depressions are related to life stress?

This paper examines the relationship of recent life events to specific kinds of depression using published studies and the author's own work. An overall effect of life events on depression has been found consistently and is moderate in degree. In suicide attempts there are stronger and more immediate effects than in depression. Life events precede both non-melancholic and melancholic depressions. It is only in recurrent depressions that life events are less common with melancholic pictures. Life events influence bipolar disorder as well as unipolar. Mania may be preceded by life events, particularly those involving social rhythm disruption, but it is harder to rule out events which are consequences of insidious development of illness. There are strong effects of life events and social support in postpartum depressions but in postpartum psychoses these effects are absent. Events precede depression comorbid with other disorders as well as pure depression. The course of depression is also influenced by life stress with less remission where negative events occur after onset and better outcome where earlier adverse events are neutralized. Relapse is related to immediately preceding life events. However, where depressions are both severe and recurrent life stress effects weaken and as the number of episodes increases preceding life events lessen. These findings suggest that some kinds of depression are more related to psychosocial causation and some are more biological in origin.