Course of illness in depressive and bipolar disorders. Naturalistic study, 1994-1999

Newer antidepressants have increasingly been used during the past decade. These drugs may increase compliance and reduce the risk of cycle acceleration in affective disorders.

To investigate the naturalistic longitudinal course of illness in patients with depressive or bipolar disorder following the use of recently introduced drugs.

The rates of relapse leading to hospitalisation after successive episodes were calculated in a case register study including all hospital admissions of patients with primary affective disorder in Denmark during 1994-1999. Altogether, 9417 patients had a diagnosis of depressive disorder and 1106 patients had a diagnosis of mania or bipolar disorder, at first-ever discharge.

The rate of relapse leading to hospitalisation increased with the number of previous episodes in both depressive and bipolar disorders. However, the effect of episodes was not significant for men. The rate of relapse did not decline during the study period.

The course of severe depressive and bipolar disorders has remained roughly the same despite introduction of new treatments.