Factors predicting suicide in psychotic patients.

Death rate and causes of death during a mean period of 5.8 years were investigated in 250 male inpatients with psychotic disorders (DSM-III). Fifty patients died during the observation period. Suicide was confirmed in 11 of these patients and could not be excluded in 7 cases, where the cause of death was reported as uncertain. Clinical and neurobiological characteristics (DST-non-suppression, CSF proteins, and monoamine metabolites) were compared in patients who committed suicide and non-suicide patients of the same age, with or without suicidal behaviour. A highly increased mortality rate was seen among the patients and the rate of suicide was more than 20 times higher than that expected in a normal population of the same age. The estimated annual incidence of suicide was 2.5%, 1.3%, 1.0% and 0.4% for patients with bipolar disorder, paranoid psychosis, major depression and schizophrenic disorder, respectively. The following factors were significantly positively correlated with completed suicide: depressive mood, elated mood, paranoid ideas, and paternal age. All suicides had previously shown suicidal behaviour and the suicide occurred during or shortly after a period of hospitalisation. No correlations were found with age at onset of illness, duration of illness, substance abuse or neurobiological parameters.