Cardiovascular risk factor profiles of recent immigrants vs long-term residents of Ontario: a multi-ethnic study

Background: There is growing evidence that cardiovascular risk profiles differ markedly across Canada's 4 major ethnic groups, namely White, South Asian, Chinese, and Black; however, the impact of long-term Canadian residency on cardiovascular risk within and across these ethnic groups is unknown.

Methods: Using pooled data from Statistics Canada's National Population and Canadian Community Health Surveys (1996-2007), we compared the age- and sex-standardized prevalence of cardiovascular risk factors and diseases between recent immigrants (< 15 years in Canada) and long-term residents (immigrants who lived in Canada for ≥ 15 years or people born in Canada) among White, South Asian, Chinese, and Black ethnic groups living in Ontario. We also calculated ethnic-specific attributable fraction (AF), defined as the proportion of risk that can be attributed to long-term Canadian residency.

Results: For all ethnic groups, cardiovascular risk factor profiles (ie, the percentage of people with ≥ 2 major cardiovascular risk factors, ie, smoking, obesity, diabetes, and hypertension) were worse among those with longer duration of residency in Canada. The greatest change in recent immigrants vs long-term residents was observed in the Chinese group (2.2% vs 5.2%; AF 0.47) followed by the White (6.5% vs 10.3%; AF 0.36), Black (9.2% vs 12.1%; AF 0.17), and South Asian (7.7% vs 8.2%; AF 0.03) groups. The prevalence of cardiovascular disease did not differ significantly between recent immigrants and long-term residents, irrespective of ethnic group.

Conclusions: Our results suggest that cardiovascular disease prevention strategies must consider not only ethnicity, but also the level of acculturation within each ethnic group.