Cardiovascular risk among South Asians living in Canada: a systematic review and meta-analysis

Abstract

Background: South Asians represent about 3% of the Canadian population and have a higher burden of certain cardiovascular risk factors and cardiovascular disease (CVD) compared with white people. The objective of this study was to review the literature to compare cardiovascular risk factors and disease management practices among adult South Asian and white Canadians. Methods:We searched MEDLINE, Embase, Cochrane and Cumulative Index to Nursing and Allied Health Literature databases from their inception through Feb. 17, 2014 and the reference lists of the selected articles. English-language studies of interventions and observational studies of biological mechanisms underlying CVD risk in South Asians conducted in Canada were eligible for inclusion. Where appropriate, we used random-effects meta-analyses to integrate results comparing the CVD risk profiles of South Asian and white Canadians. Results:We included 50 articles (n = 5 805 313 individuals) in this review. Compared with white Canadians, South Asian Canadians had a higher prevalence and incidence of CVD, an increased prevalence of diabetes (odds ratio [OR] 2.25, 95% confidence interval [CI] 1.81 to 2.80, p < 0.001) and hypertension (OR 1.11, 95% CI 1.02 to 1.22, p = 0.02), lower high-density lipoprotein cholesterol levels (mean difference -0.19 mmol/L, 95% CI -0.25 to -0.13 mmol/L, p < 0.001) and a higher percentage of body fat (men: absolute mean difference 3.23%, 95% CI 0.83% to 5.62%, p = 0.008; women: absolute mean difference 4.09%, 95% CI 3.46% to 4.72%, p < 0.001). South Asian people are also more sedentary, consume higher levels of carbohydrates and are less likely to smoke tobacco (OR 0.38, 95% CI 0.24 to 0.60, p < 0.001]) than white Canadians. No differences in access to diagnostic tests, outcomes following cardiovascular surgery or use of cardiac rehabilitation programs were apparent.Interpretation: Compared with white people, South Asian people living in Canada have a higher prevalence and incidence of CVD and possess a unique cardiovascular risk profile. Abstract E184CMAJ OPEN, 2(3) Research CMAJ OPEN Methods Search strategy and selectionIn consultation with an information specialist, we developed search terms for MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature and the Cochrane Registry databases to identify human studies reporting associations among South Asian ethnicity, CVD risk factors and CVD. The initial search (conducted May 21, 2013) captured articles from database inception through May 2013; at the request of the CMAJ Open editors, the search was updated through to Feb. 17, 2014 (Appendix 1, available online at www.cmajopen.ca/content/2/3/E183/suppl/DC1). Three investigators (A.R., R.dS. and S.S.A.) each screened a third of the titles and abstracts of the studies identified in the electronic search to arrive at a list of articles for full-text review. The same 3 reviewers assessed the eligibility of these fulltext articles. Disagreements were resolved by discussion and consensus. Studies that were not p...

Cardiovascular Disease in South Asian Migrants

“…In a meta-analysis of SA living in Canada, SA were approximately 60% less likely to smoke, 19 and lower smoking rates in SA have been found in the Netherlands and UK. 11,131,132 However, in a study in Ontario, Canada, longer duration of residence in Canada was associated with rise in CVD risk factors in SA, largely due to increases in smoking.…”

“…With respect to traditional risk factors, a recent systematic review of SA in Canada showed that compared to other ethnic groups, SA had a greater prevalence of type 2 diabetes mellitus (DM), insulin resistance (IR), increased visceral adiposity, body fat, lower high density lipoprotein (HDL), increased carbohydrate intake and decreased physical activity. 19 DM was the most consistently elevated risk factor with a 1.4-2.5 fold increase in DM among SA compared to Europids. This may reflect the increased rates of abdominal obesity in SA compared to Europids.…”

“…Prior reviews have also suggested variation with respect to individual risk, contextual factors, and compliance with rehabilitation within SA as well as across health systems, and this may account for the variable prognosis of SA with CAD. 19 …”

“…11 However, the increased burden of CAD in SA may not be fully accounted for by traditional risk factors alone and novel risk factors such as unique genetic polymorphisms or elevated lipoprotein (a) may also contribute to the elevated CAD in SA. 19,27,28 …”

The Risk of Ischemic Heart Disease and Stroke Among Immigrant Populations: A Systematic Review

“…South Asian individuals who live in Canada have been shown to have a greater burden of certain risk factors and subclinical disease but longer-term outcomes data are limited. 52 The role of socioeconomic status on risk of IHD and stroke among immigrants should also be further explored. Finally, the contribution of variance in cardiovascular risk factors to differences in cardiovascular risk should be evaluated, because few studies included in this review examined risk factor profiles.…”