Underlying
illness risk factors for severe COVID-19 or death
BMJ
 |
The risk of death increases in the
over 50s, as does being being male, obese, or having underlying heart, lung,
liver and kidney disease.
As the largest prospective
observational study reported worldwide to date, it provides a comprehensive
picture of the characteristics of patients hospitalised in the UK with covid-19
and their outcomes.
Because the study is ongoing, it has now recruited over 43,000 patients. The findings will help health professionals learn more about how the illness progresses and enable us to compare the UK with other countries, say the researchers.
Studies in China have reported risk
factors associated with severe covid-19, but studies describing the features
and outcomes of patients with severe covid-19 who have been admitted to
hospital in Europe are lacking.
To address this knowledge gap, a
team of UK researchers analysed data from 20,133 patients with covid-19
admitted to 208 acute care hospitals in England, Wales, and Scotland between 6
February and 19 April 2020.
This represents around a third of
all patients admitted to hospital with covid-19 in the UK. The average age of
patients in the study was 73 years, and more men (12,068; 60%) were admitted to
hospital than women (8,065; 40%).
Besides increasing age, and
underlying heart, lung, liver and kidney disease -- factors already known to cause
poor outcomes -- the researchers found that obesity and gender were key factors
associated with the need for higher levels of care and higher risk of death in
hospital.
At the time of publication, just
over a quarter (26%) of all covid-19 patients in hospital had died, 54% were
discharged alive, and a third (34%) remained in hospital. Outcomes were poorer
for those requiring mechanical ventilation: 37% had died, 17% had been
discharged alive, and 46% remained in hospital.
The pattern of disease we describe
broadly reflects the pattern reported globally, say the researchers. However,
obesity is a major additional risk factor that was not highlighted in data from
China. They suspect that reduced lung function or inflammation associated with
obesity may play a role.
This is an observational study, so
can't establish cause, and the researchers point to some limitations that may
have affected their results. Nevertheless, they say this is the largest study
of its kind outside of China and clearly shows that severe covid-19 leads to a
prolonged hospital stay and a high mortality rate.
"Our study identifies sectors
of the population that are at greatest risk of a poor outcome, and shows the
importance of forward planning and investment in preparedness studies," they
write.
These results have already been
shared with the UK Government and World Health Organisation, and are being
compared with data from other countries around the world.
At the outset of the covid-19
pandemic, it was natural to focus first on the people with severe disease who
might need potentially scarce resources in hospital and intensive care, write
US researchers in a linked editorial.
Cohort studies of such patients are
important, they say, and this study is a testament to good planning and preparation
before, and implementation of data collection during a pandemic.
But they add that if we are going to
be managing covid-19 for the next several years, "we need to understand
and optimize care before, during, and beyond the hospital."