A study based on data from more than 17 million British adults – the largest its kind – has identified the key risk factors that make some people more likely to die from Covid-19 than others.
The paper, which was published in the science journal Nature this week, analysed data on 17,278,392 adults from the UK's National Health Service over a three-month period. During that time, 10,926 of the participants died from Covid-19 related deaths.
The research aligns with previous, smaller studies that indicate age, race and deprivation are among the risk factors to succumbing to Covid-19.
“A lot of previous work has focused on patients that present at hospital,” said Dr Ben Goldacre of the University of Oxford, one of the researchers behind the study. “That’s useful and important, but we wanted to get a clear sense of the risks as an everyday person. Our starting pool is literally everybody.”
Here are 10 factors that were found to increase vulnerability to Covid-19:
The study found that virus patients older than 80 were at least 20 times more likely to succumb to the disease than people in their 50s, and hundreds of times more likely to die than those below the age of 40.
A strong link was found between deprivation and increased morbidity.
Researchers believe that the mortality risk associated with living in poverty may increase over time.
Diabetes patients were found to be at higher risk, particularly those with poor control over blood sugar levels. Similar trends have been found in previous studies.
Researchers found that people suffering with severe asthma, a form of the condition which requires treatment with oral corticosteroids, were more likely to die from Covid-19.
Those with severe asthma were more than double as likely to die from the disease compared with mild asthmatics.
Men who had contracted the virus had a higher likelihood of dying that women of the same age.
Other studies have also shown this, though experts are still unable to explain why this might be.
As the first major study that reviewed sex differences was in China, it was initially thought to be linked to smoking – as over half of Chinese men smoke while few Chinese women do.
But more recent studies have found the sex difference in different countries, suggesting that female biology – such as oestrogen and the X chromosome – could be behind the increased susceptibility for men.
After removing other variables to focus solely on race and ethnicity, the Oxford University researchers found that non-white individuals – particularly black and South Asian people – were at higher risk of dying from Covid-19 than white patients.
The reasons for this were unclear, but previous research has indicated that this is because people of South Asian descent are more likely to suffer from diabetes than other ethnicities.
Anyone with a body mass index (BMI) above 40 was found to be significantly more likely to die from the disease compared those with lower BMI scores.
Two previous studies in France and New York indicated that obese Covid-19 patients need more treatment.
UK Prime Minister Boris Johnson reportedly believed that his obesity was one of the reasons why he was rushed to hospital after he caught the virus.
Heart, kidney, liver and respiratory diseases
Having chronic diseases affecting any of these organs increase the liklihood of dying of Covid-19, researchers found.
The results agree with a study of hospitalised UK patients with the disease that indicated increased risk of death with cardiac, pulmonary and kidney disease, malignancy, obesity and dementia, and a large Chinese study which, though lacking age correction, suggested cardiovascular disease, hypertension, diabetes, respiratory disease, and cancers to be associated with increased mortality.
Stroke and dementia sufferers
The Oxford study found that those who had suffered a stroke and deterioration from dementia were likely to die from the coronavirus. The UK's Stroke Association warned on Thursday that it had to suspend three quarters of its funded research – amounting to £1.5 million (Dh7 million) – due to the coronavirus pandemic.
Compromised immune system
Autoimmune diseases like rheumatoid arthritis, lupus or psoriasis were also found to increase the risk of dying from Covid-19.