Diagnostic Procedures, Revascularization, and Inpatient Mortality After Acute Myocardial Infarction in Patients With Schizophrenia and Bipolar Disorder

Abstract

To investigate inpatient mortality and the use of invasive diagnostic and revascularization procedures after acute myocardial infarction (AMI) in people with schizophrenia and bipolar disorder. A case-control study was nested within the first AMI episodes between 1996 and 2007 using nationwide data. Participants with schizophrenia or bipolar disorder were compared with a random sample of all other adults without severe mental illness. Inpatient mortality and receipt of cardiac catheterization, coronary arteriography, percutaneous transluminal coronary angioplasty, and coronary artery bypass graft were compared in logistic regression models after adjusting for demographic and health status, hospital type, and AMI complications. A total of 3361 adult patients who had incident AMI between 1996 and 2007 were identified. Patients with schizophrenia and bipolar disorder (n = 834; 24.8%) had a significantly decreased likelihood of catheterization (12.2% and 14.0%, respectively) and revascularization (9.0% and 12.8%, respectively) during the index AMI episode compared with controls (27.9% of whom received catheterization and 23.9% of whom received revascularizations). Inpatient mortality remained 2.68 times the rate in patients with schizophrenia (95% confidence interval = 1.73-4.15; p < .001) compared with controls after adjusting for intervention receipt among other covariates, but mortality was not significantly raised in patients with bipolar disorder. In a large national sample and in the context of a comprehensive free health service, patients with schizophrenia and bipolar disorder were substantially disadvantaged, being half as likely to receive catheterization or revascularization procedures after AMI. Further research is required to clarify the reasons for this.