High prevalence of cardiovascular disease in South Asians: Central role for brown adipose tissue?

Abstract

Cardiovascular disease (CVD) is the leading cause of death in modern society. Interestingly, the risk of developing CVD varies between different ethnic groups. A particularly high risk is faced by South Asians, representing over one-fifth of the world's population. Here, we review potential factors contributing to the increased cardiovascular risk in the South Asian population and discuss novel therapeutic strategies based on recent insights. In South Asians, classical ('metabolic') risk factors associated with CVD are highly prevalent and include central obesity, insulin resistance, type 2 diabetes, and dyslipidemia. A contributing factor that may underlie the development of this disadvantageous metabolic phenotype is the presence of a lower amount of brown adipose tissue (BAT) in South Asian subjects, resulting in lower energy expenditure and lower lipid oxidation and glucose uptake. As it has been established that the increased prevalence of classical risk factors in South Asians cannot fully explain their increased risk for CVD, other non-classical risk factors must underlie this residual risk. In South Asians, the prevalence of "inflammatory" risk factors including visceral adipose tissue inflammation, endothelial dysfunction, and HDL dysfunction are higher compared with Caucasians. We conclude that a potential novel therapy to lower CVD risk in the South Asian population is to enhance BAT volume or its activity in order to diminish classical risk factors. Furthermore, anti-inflammatory therapy may lower non-classical risk factors in this population and the combination of both strategies may be especially effective.

Regulation of Adipose Tissue Metabolism by the Endocannabinoid System

“…In all, there is a positive association between CB1R blockade and BAT thermogenic activity. Conversely, serum endocannabinoid levels are higher in the South Asian population [76], who are known to have reduced BAT volume and activity, increased visceral adipose tissue depots, and an elevated risk for metabolism-related diseases such as cardiovascular diseases and type 2 diabetes, compared to the white Caucasian population [77,78]. Further studies will be necessary to demonstrate a causal relationship between high ECS tonus and reduced BAT activity.…”

Regulation of visceral and epicardial adipose tissue for preventing cardiovascular injuries associated to obesity and diabetes

“…1). In some South Asians populations, the lower amount of BAT can explain their frequent metabolic and cardiovascular disorders such as obesity, insulin resistance, T2DM, and dyslipidemia [65]. A reduced activity of BAT may predispose subjects to T2DM not only by increasing obesity, but also through a direct pro-diabetic mechanisms, such as by reduction of glucose uptake [59, 64].…”

Shrinking Urban Greenspace and the Rise in Non-communicable Diseases in South Asia: An Urgent Need for an Advocacy

“…South Asia hosts nearly a quarter of world's population. A third of the population in this region develops cardiovascular diseases (CVDs) during their lifetime with a higher incidence among urban residents (Boon et al, 2015). In India alone, the disability-adjusted life years from CVDs increased by nearly 2.3-fold in the last 25 years (India State-Level Disease Burden Initiative CVDC., 2018); the prevalence of hypertension is expected to reach 42 million in 2025 compared to 5 million in 2000 and diabetes 57 million compared to 23 million in 2000 (Sharma, 2008).…”