Risk of acute myocardial infarction and related medical care receipt in people with serious mental illness

Abstract

Background:People with serious mental illness (SMI, including schizophrenia and bipolar disorder) experience adverse health and premature mortality. Higher incidence and/or worse outcome of acute myocardial infarction (AMI) may partly underlie this.

Objectives:To investigate the relative risk of AMI in adult patients with SMI. To compare receipt of invasive coronary intervention, inpatient mortality, and recurrence of cardiovascular diseases following AMI between patients with and without SMI To investigate the association between AMI and recent antipsychotic exposure among people with SMI

Design: Historic cohort study for the first two objectives and a case-crossover design for the third objective.

Setting: The Taiwan National Health Insurance Research Database (NHIRD).

Participants: For the first two objectives, adult patients with diagnoses of schizophrenia or bipolar disorder were compared to general population controls. For the third objective, a ‘case-crossover design’ was utilized, with antipsychotic exposures compared between a ‘case period’ (proximal to the index AMI) and a ‘control period’ (more distal to the index AMI).

Main Outcome Measures: Adjusted hazard ratios of AMI were calculated using Cox regression. Invasive coronary interventions and outcomes were compared in logistic regression models. Odds of antipsychotic exposure in case and control time periods were compared within individuals using conditional logistic regression models.

Results: Overall, no increased risk of AMI was found in people with SMI, apart from in sub-group analyses (suggesting an excess SMI-associated risk in younger women). Patients with schizophrenia and bipolar disorder were less likely to receive invasive coronary interventions following AMI episode compared to controls, and inpatient mortality was higher in patients with schizophrenia compared to controls. AMI was significantly associated with more recent antipsychotic exposure in schizophrenia but not in bipolar disorder.

Conclusion: Schizophrenia and bipolar disorder were only associated with raised risk of AMI in young women, but post-AMI care was less adequate in both conditions. A short-term risk of AMI following antipsychotic exposure in schizophrenia was suggested.

Date of Award	2013
Original language	English
Awarding Institution	King's College London
Supervisor	Robert Stewart (Supervisor) & Martin Prince (Supervisor)