Exploring the convergence of cardiometabolic conditions and pandemic preparedness in Africa
“Nothing happens in isolation,” said STIAS permanent fellow Abdallah Daar of the Faculty of Medicine and Dalla Lana School of Public Health, University of Toronto. “Everything is connected to everything else. There is a convergence of cardiometabolic conditions and pandemic preparedness that we need to explore.”
Daar presented a seminar which explained cardiometabolic conditions, their risk factors and why we should care about them; the COVID-19 pandemic and the lessons learnt from it and other infectious pandemics; the underlying social, political and economic factors that influence health; and the advantages of thinking about convergence.
“My focus is to keep thinking about how we can impact health in Africa” he said. “Much of this continent is beautiful and charming, but we need innovative solutions to address the challenging health problems.”
Cardiometabolic diseases are common but preventable. They include cardiovascular diseases (mainly heart disease and stroke), diabetes and non-alcoholic fatty liver disease. There has been a global increase in people experiencing one or more of these conditions in their lifetime.
“Cardiovascular disease specifically is the number one cause of death globally, causing nearly 18 million deaths annually, three-quarters of which occur in low- and middle-income countries,” said Daar.
“The life expectancy gains in the past 20 years in Africa as a result of fighting HIV, malaria, etc. have been wiped out by the dramatic increase in cardiometabolic diseases. This is why we should care. We have gained 20 years and lost 20 years.”
He added that the incidence of stroke is particularly high in Africa, mostly caused by underlying untreated high blood pressure, which he described as “the silent killer”. Stroke is also occurring more in younger people – even those in their 20s.
The risk factors for cardiovascular diseases include age, gender, family history, untreated hypertension, diabetes and pre-diabetes, high cholesterol, smoking, lack of sleep, stress and loneliness.
Daar pointed out that stress is increasingly becoming a problem in younger people leading to anxiety and mental illness. “It’s rare now to find a young person without stress,” he said. “Something that didn’t exist to this extent 10 years ago. Long-term stress and anxiety can lead to poor heart health and health generally later in life.”
He also pointed to loneliness and social isolation as a surprising risk factor for heart disease.
“For diabetes there has been a dramatic increase in type-II diabetes globally, more so in LMICs,” he said. “Approximately one in ten adults will develop it in their lifetime. It’s a pandemic. Type-II diabetes is a major cause of blindness, kidney failure, heart attack, stroke and lower limb amputations. It causes approximately two million deaths per annum, most in people under the age of 70.”
The World Health Organization predicts that diabetes will be the seventh leading cause of death by 2030. (As an aside Daar mentioned that 2021 was the centenary of the discovery of insulin at the University of Toronto.)
“There is a huge socioeconomic cost to all these conditions,” he added.
But most of these conditions can be prevented by addressing behaviour – including diet, obesity, physical inactivity, harmful alcohol use, and, in particular, reducing high intakes of sugar, salt and trans fats. “Governments could easily reduce salt intake,” he said. “It would cost very little to do so.”
The burden of these conditions can also be mitigated with appropriate healthcare – including early screening and clinical interventions. “Lack of appropriate healthcare, especially in LMICs, leads to unnecessary deaths,” said Daar.
COVID – a continuing global emergency
Turning to COVID-19, Daar pointed out that it’s estimated to have killed up to 20 million people globally.
“mRNA vaccines were developed quickly and more oral antivirals are being developed currently, but,” he said, “vaccine inequity remains a big issue. Furthermore, long COVID is emerging as a major, long-term health problem.”
“Vaccines were available in great numbers in Europe and the United States while there were very few available for people in the developing world. We have to avoid this in future.”
Looking specifically at COVID in Africa, Daar described it as presenting “an interesting picture but the data are unreliable and difficult to access”.
“Africa was not hit as badly as initially predicted. The reasons include the younger age of African populations, the fact that Africans experience repeated infections with other microorganisms so their immune systems may already be primed, as well as the effect of malaria.”
“There is cross immunity because of shared immune-dominant epitopes between malaria and COVID,” he explained. “also, use of anti-malarial drugs could be a reason for the low incidence and fatality rate in malaria-endemic regions.”
“Most cases were recorded from South Africa but that’s probably mostly due to the better data and scientific infrastructure which also allowed the speedy identification of the omicron variant here.”
“There are also plans to manufacture mRNA vaccines in Africa – which will probably happen in South Africa first.”
And what about HIV/AIDS?
We also cannot ignore the long-term HIV/AIDS pandemic, particularly in Africa.
“About 113 million people have become infected since the start of the pandemic in the early 1980s, and up to 48.6 million have died from AIDS-related illnesses,” said Daar. “About two thirds of new infections are in Africa. There is no cure, and no approved vaccines but there are antiretroviral medications, which, when used long-term, have made HIV/AIDS a chronic condition. We also know that pre-exposure prophylaxis, circumcision and condom use are effective at preventing HIV infection in the first place.”
Daar also pointed to the interventions and resources of global organisations like the US President’s Emergency Plan for AIDS Relief (PEPFAR) and the Joint United Nation’s Programme on AIDS (UNAIDS) that have made a substantial difference in HIV/AIDS testing, management and care.
“PEPFAR is estimated to have saved 25 million lives,” he said. “UNAIDS, which is now led by a Ugandan – Winnie Byanyima – has an aspirational vision of zero new HIV infections by 2030.”
So what do all of these pandemics have in common? We must consider the social, economic and political issues and inequities that underlie them.
Daar outlined the social determinants of health – the non-medical factors that influence health outcomes. These include income and social protection, education, unemployment and job security, working life conditions, food insecurity, housing, early childhood development, social inclusion and non-discrimination, structural conflict and access to affordable health services.
These always-present issues have been substantially worsened by global events since 2020 including the Ukraine War, which has contributed to raising the cost of living, food insecurity, poverty, led to the debt crises and destabilised other countries and populations. Climate change, particularly exceptional crisis events like floods and droughts across the world, is also leading to further destabilisation.
“A convergence of all the major issues that contribute to pandemics – policies, resources, inequities – are the same for cardiometabolic diseases and the COVID-19 pandemic (as they have been for HIV/AIDS). So addressing both cardiometabolic diseases and pandemics should be done together. You can’t pick and choose, everything is related.”
“COVID was predicted but the world was unprepared,” he added. “There will be another pandemic – perhaps bird flu (H5N1), although it is not yet transmissible to humans and there are vaccines for it.”
He pointed out that the WHO is developing a Global Pandemic Treaty to strengthen prevention, preparedness and response. “So people are thinking about and putting resources to the problem. It might be better next time.”
“Last year here at STIAS I presented my vision for a Collaboratory – a networked, collaborative entity that can work quickly and flexibly to prepare and study issues around pandemic preparedness focused on Africa.” (See https://stias.ac.za/2022/03/need-for-african-collaboration-for-pandemic-studies/)
He emphasised that we have to learn the lessons of COVID-19, which was highly politicised from the beginning. This includes understanding the impact of measures like lockdowns, school closures and travel bans as well as the malign influence of disinformation and misinformation.
He introduced the concept of syndemics. It’s a theory which integrates disease concentration – the co-occurrence or clustering of multiple epidemics as a result of large-scale political and economic forces and adverse social conditions; and disease interaction – the ways that overlapping epidemics exacerbate the health effects of adverse social conditions, either through biological interactions between disease states or through interactions between biological and social processes.
“By looking for convergence between cardiometabolic conditions and pandemic preparedness we can bring together and examine all the risk factors, fully unpack the policy implications of pandemics, combine resources and broaden our understanding of how inequities underlie both,” he said.
“I believe Africa has to find its own way. We need to think big and bold.”
Michelle Galloway: Part-time media officer at STIAS
Photograph: Noloyiso Mtembu