In a recently published study, researcher Stephen Elledge from Harvard Medical School has described converting the coronavirus disease (COVID-19) death toll from individual deaths to “person-years” lost in order to provide a more accurate picture of the pandemic’s toll on the population.
*Important notice: medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.
Elledge has estimated that as of early October 2020, more than 2.5 million person-years of life have been lost due to the pandemic, in just the US alone.
This corresponds to an average loss of 13.25 person-years for each COVID-19-related death, he says.
This astounding cost will probably surprise many people, given the apparent public view that COVID-19 mainly affects elderly individuals and is of less concern to other age groups, writes Elledge.
In fact, the study showed that almost half of the potential years of life lost occurred among non-elderly populations.
The COVID-19 pandemic has meant the loss of millions of years of productive, active, and happy existence, says Elledge. This loss of person-years is also associated with indirect costs due to the emotional and economic burden placed on the families, friends, and colleagues of individuals lost to the disease.
A pre-print version of the paper is available in the server medRxiv*, while the article undergoes peer review.
PYLL distribution by sex and age. (A) Person-yeast lost by age. (B) PYLL by sex.
Some countries have been more affected than others
Since the COVID-19 pandemic began in Wuhan, China, late last year, the causative agent - severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) - has spread at an unprecedented rate, causing tens of millions of infections and more than one million deaths.
The pandemic has affected different countries to varying degrees, with profound effects on Italy and Spain, for example, while in South Korea, morbidity and mortality rates were significantly lower.
The United States has been particularly affected, with the country experiencing 20% of the cases worldwide, despite only accounting for 4% of the global population.
Misunderstandings over COVID-19 severity and fatality
Elledge says there is a significant misunderstanding surrounding the severity and fatality of COVID-19, with many people under the impression that because the disease predominantly affects elderly individuals who were already approaching a natural death, the impact on the rest of society is minimal.
This assumption overlooks the fact that as a person ages, their life expectancy increases, beyond what it would have been at birth, which is generally the value most familiar to the public. It also overlooks the fact that a substantial number of individuals who would have had decades of further life expectancy have also died from COVID-19.
Furthermore, the clinical course of disease is highly variable. Some individuals experience mild or even no symptoms, and others experiencing severe respiratory distress, pneumonia, arrhythmia, liver and kidney distress, and hyperinflammatory responses.
Some of these health problems can result in long-term disability, the magnitude of which would only become apparent over a long period of time.
“Case fatality rates and total mortality are inadequate measures to portray the true impact of the disease on a population,” says Elledge. “Quantifying the impact of the COVID-19 pandemic is critical for the public and policymakers to be properly informed as to the societal cost of the pandemic in order to rationally determine how best to minimize the social costs of the disease.”
Providing a better metric for the impact of COVID-19
To provide a better metric for the demographic impact of COVID-19 in the United States, Elledge calculates the Potential Years of Life Lost (PYLL) for COVID-19 as of October 3rd, 2020, using data available for the age and sex distribution of more than 194,00 premature deaths following SARS-CoV-2 infection.
The analyses showed that 2,572,102 person-years had been lost as a result of 194,087 deaths. The average number of person-years lost for each individual death was 13.25, with men losing an average of 13.93 years and women losing an average of 12.45 years.
“This is an astounding cost and surprising given the apparent public misperception that COVID-19 is a disease that disproportionately impacts the elderly and is somehow of less concern to the rest of society,” writes Elledge.
Notably, a significant proportion of the deaths occurred among individuals in their 40s, 50s, and 60s who would have had many years of life expectancy left ahead of them.
The full impact of COVID-19 is “certain to be enormous”
“Converting the COVID-19 death toll from individual deaths to person-years lost distributed across age categories shines a light on the magnitude of the pandemic’s toll across the American population,” Elledge writes.
Although the loss of more than 2.5 million person-years might be considered a direct cost of the pandemic, the indirect costs in the form of emotional and economic burdens these losses impose on the families, friends, and co-workers of lost loved ones should also be considered, he adds.
“The full impact of COVID-19 will emerge over time, and it is certain to be enormous,” concludes Elledge.
*Important notice: medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.
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