Invasive cardiac procedure use and mortality among South Asian and Chinese Canadians with coronary artery disease

Background Previous studies evaluated cardiac procedure use and outcome over the short term, with relatively few Asian patients included. Objectives To determine the likelihood of undergoing percutaneous coronary intervention and coronary artery bypass grafting, and survival during 10.5 years of follow-up after coronary angiography among South Asian, Chinese and other Canadian patients. Methods Using prospective cohort study data from two large Canadian provinces, 3061 South Asian, 1473 Chinese and 77,314 other Canadian patients with angiographically proven coronary artery disease from 1995 to 2004 were assessed, and their revascularization and mortality rates during 10.5 years of follow-up were determined. Results Compared with other Canadian patients, South Asian and Chinese patients were slightly less likely to undergo revascularization (risk-adjusted HR 0.94, 95% CI 0.90 to 0.98 for South Asian patients; and HR 0.94, 95% CI 0.88 to 1.00 for Chinese patients). However, South Asian patients underwent coronary artery bypass grafting (HR 1.00, 95% CI 0.94 to 1.07) and Chinese patients underwent percutaneous coronary intervention (HR 0.96, 95% CI 0.89 to 1.04) as frequently as other Canadian patients. Although the 30-day mortality rate was similar across the three ethnic groups, the mortality rate in the follow-up period was significantly lower for South Asian patients (HR 0.76, 95% CI 0.61 to 0.95) and marginally lower for Chinese patients (HR 0.80, 95% CI 0.60 to 1.07) compared with other Canadian patients. Conclusions South Asian and Chinese patients used revascularization slightly less but had better survival outcomes than other Canadian patients. The factors underlying the better outcomes for South Asian and Chinese patients warrant further study.