۱- Introduction

۲- Methods

۳- Results

۴- Discussion

۵- Conclusion

References

Abstract

Suicide risk in schizophrenia is a significant treatment challenge but there are few approved treatments. Electroconvulsive therapy (ECT) is a highly effective treatment for suicidality in depression but its effect on suicidality in schizophrenia is unclear. We conducted a retrospective naturalistic study of the real-world effect of ECT on expressed suicidality as assessed by item 4 of the 24-item Brief Psychiatric Rating Scale in 113 patients with treatment resistant schizophrenia receiving ECT. 19.5% of patients expressed suicidal ideation pre-ECT of which 86.4% experienced an improvement in expressed suicidality after an average of 10.2 (SD 2.7) sessions of ECT. Changes in suicide scores before and after ECT was examined using a generalized estimating equation (GEE) model which showed that the effect of ECT on suicide was significantly mediated by depression and explained 72.2% of the decreased in expressed suicidality. ECT is effective in decreasing depression and expressed suicidality in patients with schizophrenia and should be considered as a treatment option for managing suicidality and psychosis in patients with treatment resistant schizophrenia.

Introduction

Schizophrenia is a chronic severe mental illness with premature mortality that is partially accounted for by increased suicides (Palmer et al., 2005). The lifetime risk of suicide in schizophrenia is estimated to be as high as 13% (Drake et al., 1985) and 8.5 fold that of the general population (Harris and Barraclough, 1997). Despite this high risk of suicide, there are few approved treatments to address suicidality in schizophrenia (Kasckow et al., 2011). Only clozapine is US FDA approved to treat suicidality in schizophrenia (Meltzer et al., 2003) and SSRIs may be helpful to decrease suicidality in schizophrenia (Zisook et al., 2010). Electroconvulsive therapy (ECT) is the oldest somatic treatment modality in psychiatry still in current use (Cerletti and Bini, 1938). It is the most effective acute treatment for severe depression (Carney et al., 2003) and also effective in reducing psychotic symptoms in treatment resistant schizophrenia (American Psychiatric Association, 2008; Petrides et al., 2014; Tharyan and Adams, 2005). ECT is highly effective in rapidly decreasing suicidality in depression (Fink et al., 2014; Kellner et al., 2005; Prudic and Sackeim, 1999) and can be life saving for some patients. However, the effect of ECT on suicidality in schizophrenia is unclear. We thus set out to investigate the effect of ECT on expressed suicidality in schizophrenia in a large naturalistic cohort of patients with treatment resistant schizophrenia receiving ECT. Singapore is a small nation state at the tip of the Malaysian archipelago. It has a population of approximately 5.5 million people consisting of 74.3% ethnic Chinese, 13.3% Malays and 9.1% Indian (Department of Statistics Singapore, 2016). The Singapore Institute of Mental Health (IMH) is the only tertiary psychiatric hospital in Singapore and has 1900 inpatient beds and about 40,000 outpatients. The IMH treats about 80% of the national load of patients with schizophrenia. At the IMH, ECT is prescribed primarily for schizophrenia (47%) with schizoaffective disorder (20.3%), depression (20.4%) and mania (6.8%) being the other major indications. ECT was effective in treating psychotic symptoms in 64.5% of patients with schizophrenia and also improved cognitive functioning in these patients (Tor et al., 2017).