The potential impact on heart and brain disease poses challenges to healthcare systems globally.
When Dr David Strain encountered a 64-year-old patient on his ward round, the British geriatrician had a bleak epiphany.
Less than six months earlier he had treated the man for Covid-19. Now, his deterioration was painful to witness. "He came in with a stroke and really bad delirium, a precursor of dementia," Strain says. "I saw the patient, recognised him [and] recognised the fact that his brain had dramatically aged."
By unsettling coincidence, the same day Strain, who is based at the University of Exeter in England's west country, had read a newly published study which identified significant brain shrinkage in a cohort of about 400 people aged between 51 and 81 who had recovered from coronavirus.
The encounter crystallised Strain's belief that Covid generated a kind of epidemiological aftershock by leaving people susceptible to a huge range of other conditions, threatening global health systems already struggling with insufficient resources and ageing populations. "It made me realise that this is something that we're going to be facing in a really big way in the near future," he says.
As he started to see a rise in certain conditions in the first year of the pandemic, Strain assumed it was the result of people being unable or unwilling to access healthcare. Only as the pandemic entered its second year did he begin to suspect that Covid itself could be increasing vulnerability to other serious illnesses.
He now sees it as an inversion of the huge drop in respiratory illness doctors saw from the 1980s onwards, when millions either stopped or reduced smoking. "The level of damage that's been done to population health [during Covid], it would be as if everybody suddenly decided to take up smoking in one go," Strain says.
While more data will accumulate in the coming years, there is already evidence to back up his concerns. A Financial Times analysis of data from the UK's NHS, one of the world's richest health data sets, showed significant rises in deaths from heart disease since the start of the pandemic in all but the very oldest age groups. In the 40-64 age group, heart attack deaths increased 15 per cent in 2021 compared with 2019.
In February, meanwhile, an analysis of more than 150,000 records from the national healthcare databases at the US Department of Veterans Affairs suggested that even some people who had not been seriously ill with Covid had an increased risk of cardiovascular problems for at least a year afterwards.
Researchers found that rates of many conditions, such as heart failure and stroke, were substantially higher in people who had recovered from Covid than in similar people who had not been infected. A separate analysis of VA data, published in March, suggested that in the "post-acute phase" of the disease, people with Covid "exhibit increased risk and burden of diabetes".
"What's particularly alarming is that these are really life-long conditions," says Dr Ziyad Al-Aly, chief of research and development at the VA St Louis Health Care System and clinical epidemiologist at Washington University in St Louis, who led both pieces of research.
While just 4 per cent more people contracted heart failure following a Covid infection than those who had not been infected, "because the number of people infected with Sars-Cov-2 in the world is colossal, even small percentages will translate into huge absolute numbers.
"Will it be sufficient to elevate the burden of chronic disease and subsequently put an additional strain on healthcare systems? We think the answer is yes," he adds.
Some researchers caution it is too early to draw broad conclusions from limited data. Dr Christopher Murray, director of the Seattle-based Institute for Health Metrics and Evaluation (IHME), says the increases might also reflect inconsistencies in reporting. In the first year of the pandemic, for example, many of the deaths in older people had been assigned to dementia when they may in fact have been due to undiagnosed Covid, which had a high death rate in the very elderly. "Disentangling that is quite tricky", he says.
But although the evidence is still coming into focus, it is already becoming clearer to clinicians and health leaders in medical systems around the world that they are coping with a higher burden of disease in the population — whether from the increased susceptibility to serious illness after Covid, or from the lingering, little understood impact of long Covid, or a backlog of patients.
At the same time, over the past two years many workers have burnt out, or were lost fighting the pandemic on the front lines. "Our capacity may be shrinking at a time when the demand in the population is increasing," warns Eric Schneider, an executive vice-president at the National Committee for Quality Assurance, a non-profit organisation that focuses on improving health care quality.
This combination of rising disease levels and scarce resources is forcing medical professionals to re-evaluate the way they practise medicine and organise healthcare, putting a greater emphasis on preventive care, collaborative working, and telehealth to manage chronic disease and boost population health.
Given the many challenges healthcare professionals are facing "it's impossible to square the circle unless we are prepared to very fundamentally rethink how we deliver healthcare," says Jeremy Lim, director of the Leadership Institute for Global Health Transformation at Singapore's NUS Saw Swee Hock School of Public Health.
'You have to think of the whole patient'
Many of these changes were under consideration before the pandemic struck, especially in countries with ageing populations. But the crisis has accelerated their implementation while also serving as a kind of large-scale demonstration project for the advantages of a different approach.
One lesson the pandemic has taught, say experts, is the degree to which different conditions intersect, and how that affects patients' potential to recover.
"I do think the connection between chronic disease risks, like diabetes and obesity, and infectious disease outcomes, which people knew abstractly, [has] become so tangible during Covid that it is breaking down some of those barriers," says Murray.
For infectious diseases specialists like himself, he says, the past two years had led to a growing awareness that "you have to think of the whole patient. You can't think of managing pandemics, or infectious threats, as distinct from good management of primary care and general health of the community and patients."
The effect of that may be greatest in middle-income countries, he argues, where "a lot of health policies are still focused on maternal and child health and infectious disease. And now the connection to diabetes, heart disease and chronic conditions is so obvious that we will see more health system interest and attention on tackling those issues," he says.
Even in the rich world, however, Covid has created a new understanding of the different elements that contribute to keeping people healthy. This spans not simply medicine in its conventional sense but nutrition and decent housing, for example.
Dr Katrina Armstrong, who heads Columbia University's Irving Medical Centre, says over the last 20 years of her career, "one of the challenges in medicine has been this division between people who say 'we're public health people', and then people who say we're 'healthcare'. I think the revolution that is happening is that we are truly bringing those pieces together."
After more than two years in which doctors and nurses had witnessed the reality of their patients' home lives through a telemedicine screen "we are starting to see so many people be able to really understand the context around their patients and really engage with every part of the healthcare team," she says.
Armstrong believes that part of the solution to keeping people fitter lies in bringing healthcare closer to where they live — using telehealth, nursing programmes and community health workers to reach patients in their homes.
Columbia is also rethinking how to educate the next generation of doctors. Medical students now spend more time outside the hospital, undertaking stints in the community. A team approach is encouraged, in order to break down the barriers between different specialisms and categories of staff.
Similar lessons have been absorbed in Europe, building on the ethos established during the pandemic when normally rigid lines between different specialisms blurred amid the demands of Covid. Björn Zoëga, chief executive of Sweden's Karolinska University Hospital, one of the continent's biggest teaching hospitals, says that in a highly specialised institution such as his, "you have a lot of silos because people know a lot about one thing".
However, at the height of the pandemic, "in the [intensive care unit] we had plastic surgeons staying in the dispensary taking out the meds for the nurses because they could not operate. Everybody helped out and had a role and that made people more understanding of what [their colleagues] do. One of the things that we want to keep working on now, post-Covid, is that collaboration, that team work," he adds.
Educating and empowering
As they cope with rising demand, many health systems will have little choice but to use existing staff more flexibly. Even before the pandemic, experts calculated that the world was 6.4mn doctors and almost 31mn nurses short of the numbers needed to provide safe and high quality care.
In this context, ensuring resources meet demand may entail a more organised system of risk stratification, with patients' individual vulnerabilities calculated before decisions are taken, not only about their treatment but the level of healthcare professional who should provide it.
Dr Xavier Cos Claramunt, a Barcelona-based general practitioner and diabetes researcher, who chairs Primary Care Diabetes Europe, believes that resources are no longer sufficient to give every patient the same level of follow-up. Far more precise assessments of individual risk will be required, perhaps involving the use of artificial intelligence to interrogate big data sets.
In some instances, this could mean patients working with "coaches" rather than clinical staff to look after their health, perhaps with the support of wearables-type technology. The most highly qualified staff would then have more time to care for the patients whose conditions really warranted it.
Patients would in turn need to be educated away from reliance on a "paternalistic" model and helped to understand that they needed to take responsibility for their own health, he argues. But healthcare professionals, policymakers, patients and citizens would all have to align around the new approach if it was not simply to create "fear and resistance", he warns.
Some patients may struggle with this notion of empowerment. At Columbia, Armstrong says the pandemic taught her how many patients without health insurance relied on informal networks of support, whether from nurses at urgent care centres, pharmacists or family members. The pandemic had frayed these support structures, revealing a big gap in patients' knowledge about how to care for themselves.
"When people came in, we kind of talked at them, sent them home and assumed it was all going to be OK [but] you really have to have basic health literacy to survive in this new world order," she says.
In Singapore, Jeremy Lim acknowledges that structures must be kept in place for those who, perhaps for reasons of disability or discomfort with technology, are not able to take their health destinies into their own hands.
Yet even if only 50 per cent of patients were able to take charge in this way, "that means that there's 50 per cent of the resources freed up to care for those patients who otherwise would have gotten five minutes with a doctor when they should have gotten 35," he says.
As an example, Lim pointed to patients who would previously have visited their family physician four times a year for blood pressure checks but could now take their own measurements automatically via their phones, with the result uploaded to a system that a doctor or nurse could track remotely. An algorithm would flag up outliers.
One of the big discoveries of the pandemic was that technology and self-testing are key to enabling health systems to cope with a workforce that does not rise in line with demand, he says. "We in healthcare have always felt that we were unique, that healthcare is very, very bespoke and that the more patients you had, the more healthcare professionals you needed."
That calculus had shifted during the Covid crisis, moving the sector closer to the model of financial services, in which physical visits to a bank are reserved for complex transactions such as mortgages, with more quotidian needs met online. "I think over the last two and a half years we have learned which types of health conditions are amenable to telemedicine, [for] which types of diseases patients can actually self-help," Lim says.
Far from being a solution that was only practicable in wealthier countries, "I would argue it needs to happen in the developing world even more because resources are much more constrained. The rich world has the luxury of being inefficient to some extent, but the developing world has no choice but to be clever."
A long-term challenge?
Even as health systems around the world adjust to what many fear will be an era of structurally higher demand for healthcare, researchers and clinicians remain divided on how irrevocably the landscape of illness has been reshaped by Covid.
The IHME's Murray believes that more data is needed to draw firm conclusions. "What will the future trajectory for people's health be once we come out of Covid? Will it look very different? That's the question. And that's the part that I think still remains to be proven," Murray says. "This may be a three-year shock [to health], and not a shock [that will last] many, many years."
Gwenaëlle Douaud, associate professor at Oxford university's Nuffield Department of Clinical Neurosciences who led the study on brain shrinkage that shocked Strain, agrees that it is too soon to make predictions about future burdens.
"Some of these impairments — cerebral and cognitive — may partially normalise in time," she says. "Ultimately, this is something only extensive follow-up studies will be able to tell us."
But, as he prepares to publish further findings from his scrutiny of the VA database, Al-Aly is in no doubt that clinicians and society at large will be dealing with the after-effects of Covid in perpetuity. "This is not something that will go away in a week, in a year, or two, or three. This will reverberate with us for generations," he says.
In Singapore, Lim is striving to see opportunity amid the challenges. Healthcare "is now front and centre of many governments' and many global agencies' agendas. So hopefully there is much more prioritisation, there's much more investment into healthcare."
But the world's health needs have grown in the aftermath of the pandemic, he warns. "And if our tools to address healthcare demand don't change, if our models of care don't change, then let's just say we're in for a very, very bumpy ride."
Written by: Sarah Neville
© Financial Times
