[Impact of life events in the course of depression].

The impact of recent life events in the provoking of depressive episodes is well-established, but their weight in the course of depression has not been frequently studied. Some data can nevertheless be extracted from published research: First, life events occurring before the beginning of the episode are predicative neither of the response to treatment, nor of the long-term evolution of major depressive episodes. Reactional depression seem to be more sensitive to placebo than non-reactional depressions, and, minor reactional depression could have a better spontaneous course. Second, stressful life events and long-lasting difficulties contemporary with the episode are some of the more important clues for durability, and sometimes chronicity, of depressive symptoms. Some of those events are independent (not controlled by the subject), but some are also dependent, produced by the subject and his depressive state. On the other hand, certain types of life events (like "neutralizing events" or "fresh start events") and the stress reduction of long-lasting difficulties, seem to favour remission of minor depressions. Third, weight of life events in relapse and recurrence of depression is significant, but seems to be less important than in the release of first depressive episodes. The interaction between life events and the genesis of depression can be observed from sociological, psychological or biological point of view. Future analysis should be based on the distinction between vulnerability factors, which modulate the impact of life events, and susceptibility factors, which can have a sensibilization role.