Predictors of Electroconvulsive Therapy Use in a Large Inpatient Psychiatry Population

OBJECTIVE: There is limited research on reliable and clinically useful predictors of electroconvulsive therapy (ECT) use. We aimed to examine factors that predict ECT use in an inpatient psychiatric population. DESIGN: Retrospective analysis of provincial database for inpatient psychiatry. METHODS: This study is a retrospective analysis of a provincial database for inpatient psychiatry. The study includes all psychiatric inpatients 18 years or older in Ontario, Canada, assessed with the Resident Assessment Instrument for Mental Health (RAI-MH) within the first 3 days of admission between 2009 and 2014 (n = 153,023). The RAI-MH is a validated assessment tool which includes a breadth of information on symptoms, self-harm, functioning, social support, comorbid medical diagnoses, and risk appraisal. Multivariable analyses were performed using SAS. RESULTS: One hundred forty-five thousand seven hundred (95.2%) of patients admitted had no history of ECT treatment and were not scheduled to receive ECT. A total of 7323 (or 4.8% of the patient population) had either a history of ECT use or were scheduled to receive ECT. Overall rate of ECT use was highest in patients with a provisional diagnosis of mood disorder (7.2%) compared with schizophrenia/other psychotic disorder (3.1%) or substance-related disorder (1.7%). Women were more likely to receive ECT compared with men (overall rates of ECT use 6.2% and 3.4%, respectively). Overall rate of ECT use increased significantly with increasing age. Number of prior hospitalizations was also a strong predictor of ECT use. Conversely, patients with elevated Risk of Harm to Others, schizophrenia, or a substance use disorder were all significantly less likely to receive ECT. All variables examined were statistically significant (P < 0.0001). Higher Severity of Self Harm Scores predicted past use, but not scheduled use of ECT. CONCLUSIONS: This is the largest study to date on predictors of ECT use. Utilization of RAI-MH is a novel and clinically useful method for evaluating predictors of ECT use. Predictors of ECT use within an inpatient population include: presence of a mood disorder, female sex, older age, low risk of harm to others, number of lifetime hospitalizations, lack of substance use disorder, and inability to care for self.