This “disproportionately high” risk was not apparent during the second wave, suggesting the number of resident deaths “may not have been inevitable”, according to an analysis of millions of GP records.
Researchers from the University of Oxford the London School of Hygiene and Tropical Medicine (LHSTM), and the healthcare technology company TPP, analysed data on almost 100,000 care home residents and more than four million older adults living in private homes.
They looked at electronic health records for people registered with GP surgeries using the OpenSAFELY-TPP platform, which covers approximately 44% of the general population in England.
They then matched the address an individual used to register with their GP to the Care Quality Commission’s registry of care homes, and compared mortality rates between those living in different settings.
They found that in the period before the pandemic, people aged 65 years or older living in care homes in England had around ten times higher mortality from all causes compared to those living in private homes.
This reflects the frailty of people who are admitted into care homes.
In the first wave (February to August 2020) this increased substantially to peak at an 18-fold difference, before returning to the pre-pandemic level in the second wave (September 2020 to March 2021, the end of the data collection period).
Potential reasons include changes in the measures taken to protect residents, such as increased, regular testing in the second wave, changing demographics in the care home population and increased immunity after surviving Covid-19 or being vaccinated.
However, due to the time it takes for immunity to develop, the authors say factors in addition to the vaccine rollout are likely to have played a part.
They said: “Our main finding is that the relative mortality of people living in care homes compared to private homes increased during the first – but not the second – wave.
“This is novel and suggests that the mortality peak observed during the first wave may not have been inevitable.”
The research also identified a large increase in non-Covid deaths in the first wave but not in the second.
Our data quantifies just how large an impact Covid-19 has had on care home residents, and in terms of mortality, this appears to have been particularly marked during the first wave
Dr Anna Schultze
This could be due to under-recording Covid-19 on death certificates in the first wave, as separate research has shown that most excess deaths in care homes occurred in homes where there was a coronavirus outbreak.
Dr Anna Schultze, a research fellow at LSHTM who led the research, said: “Our data quantifies just how large an impact Covid-19 has had on care home residents, and in terms of mortality, this appears to have been particularly marked during the first wave.
“Something changed for the second wave. This could include the demographics of care home residents, an increase in pre-existing immunity, or more effective preventative measures.
“Unfortunately, it is not possible to disentangle the role of these different factors using the data we had.
“However, we hope this finding will stimulate further work to reveal whether these changes could have been the result of care home measures introduced in 2020.”
Senior author Professor David Leon added: “Our comparisons with people in the same age group living in private households help put into perspective quite how seriously Covid has affected this frail population.
“We hope that our work will provide sound evidence that will be of value to enquiries into the pandemic including the recently announced public enquiry to be chaired by Hon Baroness Heather Hallett.”
The research is published in the Lancet Regional Health – Europe journal.