Dr. Gijs Goossens from the Department of Human Biology (NUTRIM) was invited to give a talk in a special session on ‘Obesity and COVID-19’ at this year's European and International Congress on Obesity (1-4 September). His presentation received wide attention from international media, including The Times (UK).
Obesity not only increases the risk of many noncommunicable diseases such as type 2 diabetes, cardiovascular diseases, different types of cancer and respiratory diseases, but also seems to impact communicable diseases. Accumulating evidence indicates that obesity is an independent risk factor for coronavirus disease 2019 (COVID-19) susceptibility and worse clinical outcomes.
Adipose tissue is an active metabolic organ that plays a key role in many physiological processes, including lipid and glucose homeostasis, the regulation of energy balance, and immunity and inflammation. The metabolic changes and sustained low-grade inflammation in people with obesity leave them with an impaired immune response to infections and increased viral loads when infected by viruses, resulting in poorer outcomes and recovery from infections. In COVID-19, the attempts of the immune system to eliminate the virus produce a constant stream of these cytokines, which can lead to an effect known as the 'cytokine storm', which can cause organ damage (e.g. lung injury, heart problems), leading to poor outcomes and death.
SARS-CoV-2, the virus that leads to COVID-19, enters the host cells through the angiotensin-converting enzyme-2 (ACE-2), which is part of the renin-angiotensin-aldosterone system (RAAS). The RAAS, which is overactivated in obesity, increases blood pressure and inflammation, amongst other detrimental effects. In his presentation (and related Position Paper), Goossens indicated that the increased fat mass in obesity may contribute to increased RAAS activity and inflammation in obesity, thereby providing a critical link between obesity and the increased susceptibility and worse clinical outcomes of COVID-19 in people with obesity. Since ageing is accompanied by changes in body composition, namely reduced muscle mass and increased fat mass, Goossens postulated that this may at least partly contribute to the poorer outcomes in older individuals infected by SARS-CoV-2.
Goossens further pointed out that the collision of the obesity and COVID-19 pandemics underscores the importance of understanding shared disease pathophysiology, which may steer therapeutic choices to prevent or dampen the complications of COVID-19, especially in vulnerable populations such as people living with obesity and related chronic diseases. He emphasized that obesity prevention and continuous management of obesity and related complications are highly important during the COVID-19 pandemic. Detailed phenotyping of patients with COVID-19 is essential to identify individuals or subgroups at increased risk of developing this disease, and better predict disease progression and outcomes. Currently, Gijs Goossens and his colleagues are investigating the effects of blockers of the RAAS on ACE2 expression in adipose tissue, to further explore the putative impact of the renin-angiotensin system in the development and progression of COVID-19.
For slides from Dr Goossens presentation, click here
For accompanying publication, click here