Additive effects, but no synergistic interaction of stressful life-events and genetic loading in affective disorders.

Life-event research as well as neurobiological findings point to the relevance of adverse stress for the pathogenesis of affective disorders. The well established genetic root might be related to the sensitivity to stress. In concordance, recent studies showed a synergistic interaction between genetic loading and life-events concerning the precipitation of depression, i.e. there might exist a genetic sensitization to the adverse effects of stressors. The present investigation, using information extracted from 877 case records, did not reveal a synergistic interaction concerning the age at onset and the mean frequency and duration of episodes.