Abstract P091: Temporal Trends in Incidence of Acute Myocardial Infarction and Revascularization in People With and Without Mental Illness

Objective: The objective of this study was to evaluate the temporal trends in the incidence of acute myocardial infarction (AMI) and receipt of revascularization procedures in people with and without mental illness. Hypothesis: Individuals with mental illness will have higher rates of AMI, and lower rates of revascularization compared to people without mental illness. Methods: We did a population-based study using provincial administrative data from April 1, 1998 until March 31, 2009. We identified individuals 20 years of age and older as having mental illness (psychotic disorder [PD] or mood disorder [MD]) based on physician billing claims and hospitalization data, and compared them to those without mental illness by this definition. We identified incident AMI using a validated algorithm applied to hospitalization data. We used procedure codes to identify receipt of cardiac catheterization, coronary artery bypass grafting (CABG), or percutaneous transluminal coronary angioplasty (PTCA) in those with incident AMI. Rates were age-adjusted using the 2001 Canadian census population to perform direct standardization. Relative change over time was calculated by comparing rates in 2009 to rates in 1998. Results: A total of 3,639,480 subjects were included, of whom 576,411 (15.8%) had a mood disorder only, 38,116 (1.0%) had a psychotic disorder only, and 72,430 (2.0%) had both a MD and PD. People with MD were more likely to be female, whereas those with PD were older, than the other mentally ill and non-mentally ill populations. Incidence of AMI was highest in people with PD (210 per 100,000 in 2009) and lowest in people without mental illness (160 per 100,000 in 2009), however, incidence of AMI decreased over time in all groups. Use of catheterization decreased over time in people with MD (19% relative decrease) and PD (25% relative decrease), while increasing in people without mental illness (10.8% relative increase). Use of PTCA increased in all groups except people with PD (21.1% relative decrease). Conclusions: Incidence of AMI decreased over time in people with and without mental illness, however, people with mental illness consistently had a higher incidence of AMI compared to individuals without mental illness. Use of catheterization and PTCA increased in people without mental illness while decreasing in people with PD over the study period.