Mortality of 403 patients with mood disorders 48 to 52 years after their psychiatric hospitalisation

The purpose is to analyse differences in mortality among patients with major depressive disorders (MDD), bipolar-II (BP-II), bipolar-I (BP-I) disorders and mania with or without minor depressive disorders and to identify risk factors of mortality. The sample represents all admissions for depression or mania over 5 years (1959-1963) to the Psychiatric Hospital of Zurich University, serving a large area. 403 patients were included and followed up every 5 years until 1985; thereafter, mortality data were collected repeatedly until 2009 when 352 (87 %) patients had died. Standardised mortality ratios (SMRs) were computed and survival analyses applied. With the exception of BP-II disorder, the three other diagnostic groups showed elevated SMRs. The group with mania had the highest SMR for cardiovascular deaths and the group with MDD the highest for deaths by suicide. Mortality was also high among patients with late-onset MDD. Across the diagnostic spectrum, we found differences in risk factors for mortality, such as a family history of suicides and personality type: more anxious patients with MDD lived longer, and among patients with BP disorders, more tense (aggressive) types had shorter lives. Long-term medication had a protective effect against mortality in patients with MDD during years 1-9 and in patients with BP disorders during years 1-19 after admission. We found marked differences in causes of death and risk factors between subgroups of mood disorders. For the purpose of further research, it would be recommendable to distinguish pure mania from bipolar disorders.