Burgeoning cardiovascular disease in South Asians: the need for prevention

Cardiovascular disease (CVD) is at the forefront of disease burden and deaths worldwide, with almost 18 million deaths in 2019 alone representing 32% of all deaths over the globe[1]. Approximately, 25% of the global population are South Asians (SA), including those from India, Pakistan, Bangladesh, Nepal, Sri Lanka, and despite comprising one fourth of the world’s population, 60% of CVD cases are seen in them [2]. Additionally, SAs of a younger age group, often less than the age of forty, have a greater propensity to develop coronary artery disease of a more severe course[3]. CVDs include a broad number of pathologies such as atherosclerosis, hypertension, stroke, Ischemic Heart Disease (IHD), heart failure and cardiomyopathy. Typically, IHD and strokes are the frequent type of CVD in Asians with considerable variations by regional contribution within Asia. Morbidity associated with IHD being 57% in Southern Asia, whilst stroke associated deaths preponderant in southern eastern and east Asia[4]. SAs in the United States (SAUS) have been found to be at significantly greater risk of atherosclerotic (AS) CVD compared to age-matched ethnic opposites. Similarly, compared to those of European ancestry, SAs have a two times higher risk of ASCVD with ASCVD having highest risk in Pakistanis, Indians and Bangladeshis[5,6]. Multiple reasons can account for the varying patterns of CVD seen in different populations such as undergoing different epidemiological phases, with diverse life expectancy and demographics, as well as environmental and cultural variation and genetic predisposition[7]. Proven and putative risk factors for CVDs in South Asians include obesity, dyslipidemia, diabetes mellitus, hypertension, tobacco smoking, alcohol consumption, sedentary lifestyle and various socioeconomic factors[8]. Diet, still one of the major modifiable factors for CVDs, raises major concern since overconsumption of processed food rich in saturated fatty acid and cholesterol with a simultaneous decline in energy expenditure has become fairly common amongst South Asians[7,8]. According to the INTERHEART study of myocardial infarction (MI) involving various ethnicities from 52 countries, including South Asians, the aforementioned risk factors contribute to more than 90% of MIs[9]. Although these known conventional risk factors account for majority of cases, it is worth mentioning that in a study by Forouhi et al., after adjustment of these conventional risk factors, South Asian men had a greater CHD mortality compared to their European counterparts[10] generating relevance of emerging and non-traditional risk factors such as coronary artery calcification, elevated thrombogenic markers like fibrinogen, elevated inflammatory markers like adipokines, C-reactive protein, and microalbuminuria as well to explain the residual risk[8,10]. Inflammatory markers, particularly high-sensitivity C-reactive protein (hs-CRP), are significantly associated with ASCVD risk in South Asians. Studies reveal that hs-CRP levels are higher in South Asians than in other ethnic groups, even after accounting for metabolic factors. Elevated hs-CRP correlates with insulin resistance and metabolic syndrome, common in this population, and is independently predictive of ASCVD. Additionally, an altered adipokine profile contributes to inflammation and vascular risk. South Asians have lower adiponectin levels with side by side increases in insulin resistance, impaired fibrinolysis, and endothelial dysfunction, further increasing ASCVD susceptibility[11]. While further research aimed at understanding South Asian CVD propensity and determining its risk factors is crucial, the available literature forms a firm ground for policymakers and health care professionals to encourage and implement preventative interventions promptly. Encouraging South Asians towards healthy lifestyle changes such as increased exercise, decrease consumption of carbohydrates and fats and maintenance of optimal BMI for South Asians specifically (between 18.5 to 23 kg/m2) is important[12,13]. Backes et al found that a calorie-restricted, relatively low-carbohydrate diet for 3 months amounted to weight loss, improved insulin sensitivity and associated CVD risk factors in overweight, insulin-resistant South Asian Indian women residing in the United States[14]. South Asian populations of all age groups should be targeted for identifying and reducing the risk of cardiovascular diseases in South Asians[13]. It is important to identify any obstacles to physical activity and look into alternatives while taking into account personal preferences. CVD screening and surveillance systems need to be placed as well as high health risk behaviors need to be addressed such as by increasing taxes on or adding heath warning labels to tobacco products along with providing professional smoking cessation assistance. A proper calorie count on food labels would aid consumers in making educated decisions and critical assessments of food products. Education through mass media and applications of evidence-based recommendations and preventive measures need to be incorporated[15]. The continued increase in CVD poses a grave threat to people of the South Asian ethnicity and places a significant economic burden on the health care system in terms of hospitalizations, medications, and rehabilitation services which might result in adverse health, economic and social repercussions thus necessitating urgent measures to flatten their curve in South Asians.