Cardiovascular Risk in Middle East Populations: A Call to Action.

Abstract

As a result of the number of patients migrating to Europe and the United States, there has been an increased interest in the cardiovascular (CV) risk of noncaucasian populations. Although there is now a considerable evidence regarding the prevalence and incidence of CV disease (CVD) in Hispanics, Chinese, and South Asians, a limited number of studies evaluated this risk in Arabs. Some studies suggest a high prevalence of major CVD risk factors (hypertension, dyslipidemia, and type 2 diabetes mellitus [T2DM]) in Arabs living in the Middle East. Furthermore, CVD risk appears to increase at a lower body mass index and a smaller waist circumference in Arabs than in caucasians. Accordingly, CVD mortality rates are higher in Arabs living in Western countries than in native caucasians. Genetic studies suggest that polymorphisms in various genes might play a role in the increased prevalence of metabolic syndrome (MetS) and T2DM in Arabs. On the other hand, the risk of T2DM decreases with acculturation in migrant Arabs, suggesting that environmental factors also contribute to the higher prevalence of T2DM in Arabs living in the Middle East. Indeed, physical inactivity is more prevalent in migrant Arabs than in caucasians. Moreover, lifestyle interventions are effective in decreasing the prevalence of MetS in Arab patients. In the current issue of Angiology, Panduranga et al report results from a large registry of 7930 patients with acute coronary syndrome (ACS). In this study, clinical characteristics and in-hospital outcomes are compared between Arabs and South Asians living in Saudi Arabia, Oman, United Arab Emirates, Qatar, Yemen, and Bahrain. Previous studies showed that South Asians (patients originating from India, Pakistan, Bangladesh, Sri Lanka, and Nepal) have higher CVD morbidity and mortality, particularly due to the increased prevalence of insulin resistance and T2DM. In the study by Panduranga et al, Arabs were older than South Asians and had a higher prevalence of most major CVD risk factors including hypertension, hyperlipidemia, and T2DM. Established CVD, including coronary heart disease, stroke, peripheral arterial disease, and chronic heart failure, was more common in Arabs. Major adverse outcomes, including heart failure, recurrent ischemia, reinfarction, and cardiogenic shock, occurred more frequently during hospitalization in Arabs than in South Asians. In-hospital mortality was also more frequent in Arabs, but this difference did not persist after adjustment for CVD risk factors. Similar results have been recently reported in a retrospective study in patients with ACS conducted in the Qatar. These findings suggest that Arabs are at even higher CVD risk than South Asians, a population already known to have increased CVD morbidity compared with caucasians. Despite the apparently increased CVD risk of Arabs in the study by Panduranga et al, they were less likely to be treated with evidence-based medical management during hospitalization (statins, antiplatelet agents, b-blockers, and angiotensinconverting enzyme inhibitors) and to be prescribed these agents at discharge. Moreover, Arabs also underwent percutaneous coronary intervention less frequently than South Asians. In agreement with these findings, recent studies also showed that blood pressure, lipid, and glucose targets are reached only in a minority of Arabs living in Middle East as well as abroad. Moreover, control of CVD risk factors is less frequently achieved in migrant Arabs than in native populations in the United States and Israel. Limited awareness of CVD risk factors, lack of insurance, and limited access of migrant Arabs to health care systems might play a role in these differences. Therefore, the suboptimal management of Arab patients, either without or with established CVD, might play a role in the increased CVD risk observed for this population. Overall, the results of the study by Panduranga et al suggest that Arabs represent a population of substantially high CVD risk both due to the higher prevalence of established risk factors and due to their suboptimal management. However, given the limited data regarding the association between Arab ethnicity and CVD events, there is a pressing need for more studies to identify the factors driving this relationship.