/ 17 April 2020

Building Carma: Matters of the heart and its diseases

Choose: Giving in dying will give life
Research at Stellenbosch University looks at the link between viral infections and cardiovascular disease.


The mortality rate from Covid-19 of about 5% is substantially higher than for other infectious agents such as the more common influenza virus. It therefore represents a major global health crisis that has rightfully resulted in the adoption of extraordinary measures to prevent its spread and damaging outcomes in terms of illness and death.  

This burden of disease is further exacerbated by a less well-known intersection between viral infections and the onset of cardiovascular diseases (CVD). For example, a recently published study in the Journal of the American Medical Association examined cardiovascular diseases in 187 Covid-19 patients in Wuhan and reported some interesting findings. They found that Covid-19 patients with underlying cardiovascular diseases, and displaying signs of heart injury, exhibited a significantly higher mortality rate than those without. The mechanisms driving such harmful outcomes remain unclear and requires further investigation, although it likely includes direct damage to the heart caused by Sars-CoV-2 itself. 

The authors of the study recommended more aggressive treatment for older Covid-19 patients suffering from cardiovascular complications such as hypertension and coronary artery disease. This intersection can further be expanded to include HIV with about  25-million infected worldwide and where, alarmingly, sub-Saharan Africa accounts for about 70% of the global HIV burden. Hence, with the successful roll-out of anti-retroviral treatments, HIV is increasingly managed as a chronic disease that is accompanied by a significant rise in cardio-metabolic diseases in such patients.  

In parallel, the non-infected sub-Saharan African population is undergoing a demographic transition with increased ageing and urbanisation. This shift brings its own health-related challenges. For example, urbanised South Africans display a relatively high prevalence of cardio-metabolic complications such as obesity, diabetes and hypertension that are strongly linked to poor lifestyle choices in terms of diet and exercise. Cardio-metabolic diseases are sharply increasing within this region and future projections indicate a significantly higher burden of disease over the next few decades. It is therefore clear that such a  “dual burden’’ of cardio-metabolic diseases will place an enormous strain on the well-being and health as well as the economic development of those living in sub-Saharan Africa.   

In light of this, Stellenbosch University recently launched the Centre for Cardio-metabolic Research in Africa (Carma) to help tackle the rise in cardio-metabolic diseases in Africa and eventually eradicate them. Carma aims to achieve this by targeting six main focus areas. A primary focus includes conducting high-impact research to better understand the nature and development of such diseases in sub-Saharan Africa with the aim to develop improved diagnostic tools and treatments.  

For example, there is a paucity of knowledge on the nature and extent of HIV-related CVD in Africa as most studies have been conducted in Europe and North America. A number of Carma research projects are therefore currently investigating the phenomenon of HIV- and antiretroviral treatment-related anthropometric (measurements and proportions of the human body), cardiovascular, cardio-metabolic, and vascular alterations as well as its effect on cells that line the interior surface of blood vessels. The hope is that through such longitudinal studies we will be able to describe the prevalence of cardiovascular risk factors and disease progression in people living in sub-Saharan Africa. 

Moreover, there is a strong focus on exploring potential underlying biochemical, metabolic and immunological mechanisms, as well as pursuing pre- and clinical studies to better understand obesity-mediated alterations on the functioning of the heart. This is crucial because the prevalence of obesity is increasing sharply in sub-Saharan Africa and is strongly linked to the onset of CVD. 

Such research endeavours will help to develop novel therapeutic interventions to alleviate the burden of obesity-related complications such as diabetes, hypertension and heart attacks. It is  also focusing on chemotherapy-induced cardiac damage that occurs as a side-effect of various cancer treatment regimens as well as the development of novel treatments to attenuate damage suffered during and after a heart attack.

Given its different research focus areas, we believe Carma is ideally placed to begin to counteract the vicious alliance between communicable and non-communicable diseases that are highly prevalent in sub-Saharan Africa and projected to sharply increase over the next few decades. 

In this regard, recent Carma data reveal exciting promise, in that treatments such as rooibos, green tea and honey bush potentially offer cost-effective, safe and easily acceptable supporting therapies for cardio-metabolic complications. This should prove to be quite useful in the battle to lower the rising burden of cardio-metabolic diseases and improve the health of millions of people, especially in Africa.