[Depressive disorders. Risk factors of recurrence].

The prediction of recurrence in affective disorders is very difficult and in individual cases not possible at all. Socio-demographic variables as body build, positive family history, marital status and social class, do not predict recurrence. This is probably true for sex and age, too. The impact of stressors and social support on the course is relatively weak. In this context the research on expressed emotion is of interest, as it gives some evidence that the presence of a sick spouse may increase the relapse rate. On the other hand an inadequate premorbid personality, especially a high neuroticism score, could predict recurrence. Classification of the illness is an other variable with prognostic value. Relapse rate is probably higher in endogenous than in neurotic depressions. Comorbidity and a history of other psychiatric disorders correlate with a high relapse rate. One of the best established clinical and epidemiological finding is the prognostic value of the past course. Recurrence is higher in bipolar disorders and in patients with a high number of previous episodes. An older age of onset probably increases the likelihood of recurrence. A prospective study on the course of affective disorders was initiated in Zurich in 1959. All patients suffering from affective and schizoaffective psychoses (n = 406) who were admitted to the Psychiatric University Clinic of Zurich between 1959 and 1963 were followed up every 5 years. The last assessment was carried out in 1985. On the basis of a multiple regression analysis, we tried to establish correlations of several independent variables with the length of cycles and the number of episodes per year. Correlations were only found in bipolar disorders.(ABSTRACT TRUNCATED AT 250 WORDS)