The writer is a senior fellow at Harvard University and an adviser to the UK Department of Health and Social Care
Covid-19 is perhaps the reckoning for ignoring two things that might once have seemed unrelated. Leaders were urged to prepare for a viral pandemic, and to tackle widening gaps between the health of rich and poor. Covid-19 is the reckoning. We are repeatedly told that age is the main risk factor with this virus. But so, it seems, is being poor.
“Why are you surprised?” asks my friend Jo, an intensive care nurse in the National Health Service. “It’s nothing new.” The patients Jo sees are disproportionately overweight or obese. Many have type-2 diabetes, kidney problems or hypertension. People with those conditions, she points out, were always more prone to end up in ICU. They have weakened immune systems which often relate to chronic stress from low-income jobs, poor diet and physical inactivity.
We urgently need to understand the connections between these conditions and Covid-19. In France, the US and UK, figures suggest that patients who are overweight are at significantly greater risk. In New York City, a study of 4,000 Covid-19 patients found that obesity is the second strongest predictor, after their age, of whether someone over 60 will need critical care. Surprisingly for a virus that hits the lungs, the researchers say that excess body fat seems to matter more than heart or lung disease, or smoking — perhaps because obesity triggers chronic inflammation, leaving sufferers more susceptible.
A second New York study says that being overweight is the main driver of whether younger people will be hospitalised with Covid-19. Patients under 60, the researchers found, are twice as likely to need intensive care if they have a body mass index over 30, and 3.6 times more likely to need it with a BMI over 35. Once in ICU, we must remember, survival odds are tragically only 50:50.
Looking back to the swine flu outbreak, it is clear this should have been anticipated. In 2009, 51 per cent of Californians who died from the H1N1 Influenza A were obese: this was 2.2 times more than the prevalence of obesity in the state population. Obesity is well known to be a risk factor for chronic health conditions, including strokes, heart attacks and hypertension. One group of scientists last week called on healthcare systems to start systematically measuring the “metabolic parameters” of patients: body mass index, waist circumference, glucose and insulin levels, in order to calculate their risk of complications from the disease. It is incredible this isn’t already happening.
This is not just about body weight. People of normal weights can have impaired metabolic health. A recent commentary in the journal Nature stated that “patients with type-2 diabetes and metabolic syndrome might have up to 10 times greater risk of death when they contract Covid-19”.
Both of these conditions disproportionately afflict people of south Asian and Afro-Caribbean descent, who are being hit hard. We need to know whether metabolic syndrome might in some way explain the shocking death toll of Filipino nurses in the UK and the US. They tend to give their all to the job; some may have been working without adequate protection. But are they also physically more vulnerable?
To find out, we need better data and an open debate. Last week, three-quarters of Covid-19 patients in 268 NHS ICUs were overweight or obese, according to the Intensive Care National Audit and Research Centre. Almost half were younger than 60. These figures do not include some of the oldest people, who are dying in care homes. Nevertheless, they suggest that locking down everyone over 70 may not be the best way to stratify risk.
I am not arguing that slim, fit people are safe. Our immune systems tend to weaken as we age, and our metabolisms slow down (which in turn can lead to weight gain). Experts are also looking at whether “viral load”, — repeated exposure — may explain why some young, healthy professionals treating the sick are struck down by this virus. But if this growing body of evidence is anywhere near the mark, it suggests that the UK and US will fare especially badly in the crisis. France’s chief epidemiologist has already taken a swipe at the US, warning that Americans are likely to suffer the most from Covid-19 because obesity is “a major risk factor”.
The US is the fattest nation in the OECD, and the UK is the fattest in Europe after Portugal. Both countries also have abhorrent health inequalities. In some parts of England, there is now a 12-year gap in healthy life expectancy between rich and poor. Deficient housing, pollution, insecure work, poor diets: all of these drive chronic disease, which strikes at younger and younger ages. We have loaded the dice against the poor and this is being cruelly exposed by the pandemic.
It is notable that Japan has recorded relatively low mortality rates, despite being the world’s oldest society. There are many possible explanations. But Japan has low obesity and its government has an ambitious, successful public health programme.
How might we arm our populations against this virus, and for the future? We must turbocharge public health programmes that can reverse chronic conditions such as type-2 diabetes. We should realise that lockdowns which prevent people from exercising will store up trouble. And not bracket people simply by age.
There is much more to learn about Covid-19. But it seems clear that poverty, obesity and its related diseases make some people old before their time.
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