Comparison of characteristics of suicide attempters with schizophrenia spectrum disorders and those with mood disorders in Japan

Suicidality in patients with schizophrenia is high. To clarify the characteristics of suicidal behavior in patients with schizophrenia, we investigated suicide attempters with schizophrenia spectrum disorders in comparison with patients with mood disorders. One hundred patients with schizophrenia spectrum disorders and 155 patients with mood disorders admitted to an emergency department after a suicide attempt were interviewed in detail on items concerning 1) demographic characteristics, 2) previous suicidal behavior, and 3) index suicidal behavior. Differences between the two groups were subsequently analyzed. Patients with schizophrenia spectrum disorders showed a lower incidence of previous deliberate self-harm, and a higher incidence of a subsequent suicide attempt more than 1 year after the previous suicide attempt as well as a higher lethality of index suicide attempt compared to patients with mood disorders. Furthermore, the most common motive for making a suicide attempt in patients with schizophrenia spectrum disorders was having a mental problem. This study revealed the factors associated with suicide attempts among Japanese patients with schizophrenia spectrum disorders, and the nature of these factors makes it difficult to predict future attempts. This makes clear the importance of continuous long-term follow-up with careful attention to the mental symptoms and psychological burden for such patients.