ISCHEMIC HEART DISEASE PREVALENCE AND INCIDENCE IN CANADA

Abstract

Although hospitalization and mortality rates for ischemic heart disease (IHD) have declined since the 1970s, IHD remains a leading cause of death and disability in Canada. This is the first study to estimate the incidence and prevalence of IHD at the national level in Canada from fiscal years 1999/00 to 2009/10. Data from the Canadian Chronic Disease Surveillance System (CCDSS) were used in this study. Diagnostic codes 410-414 and I20-I25 from the International Classification of Diseases Ninth (ICD-9-CM) and Tenth (ICD-10-CA) Revisions as well as procedure codes for percutaneous coronary intervention and coronary artery bypass graft were used to estimate the prevalence and incidence of IHD among individuals aged 20 years and older. These individuals were captured in the CCDSS if they received at least one hospital discharge abstract with an IHD diagnostic code or procedure code in any field or at least two physician claims with an IHD diagnostic code in a one-year period. From 1999/00 to 2009/10, age-standardized incidence rates decreased from 10.6 per 1,000 people to 6.1 per 1,000 people. Rates decreased similarly among males and females and decreased the most among individuals aged 85 years and older (from 65.1 per 1,000 to 35.3 per 1,000) over the study period. Rates increased with age and were highest among females (33.0 per 1,000 people) and males (40.6 per 1,000 people) aged 85 years and older in 2009/10. Overall, age-standardized prevalence increased from 5.5% to 6.6% during the study period. However, the prevalence peaked in 2006/07 among females and in 2007/08 among males and then slowly started to decline through to 2009/10. IHD prevalence increased with age for both males and females. As with incidence, the highest prevalence was observed among females (38.6%) and males (46.3%) aged 85 years and older in 2009/10. The incidence of IHD declined and the prevalence increased between 1999/00 and 2009/10. Much of this decline in the incidence and increase in the prevalence of IHD may be due to improved primary prevention, management and treatment of cardiovascular diseases in Canada. However, with the continued increase in the number of seniors aged 65 years and older, it is too early to conclude whether this trend will be maintained.