At least 20 million years of life have been lost to COVID-19, study suggests

The COVID-19 pandemic may have resulted in an astonishing 20 million years of life lost worldwide, according to estimates from a new study. On average, each person who died lost 16 years of life.

The study researchers — from Pompeu Fabra University in Barcelona, Spain, and the Max Planck Institute for Demographic Research in Rostock, Germany — analyzed data from more than 1.2 million people in 81 countries who have died of COVID-19 so far. (The researchers used information from a database of confirmed COVID-19 cases and deaths known as COVerAge-DB, which includes data from 112 countries. The analysis included all countries with at least one COVID-19 death as of Jan. 6, 2021.) Then, they calculated "years of life lost," or the difference between a person's age at death and their life expectancy, using data on life expectancy in these countries. 

Overall, more than 20.5 million years of life were lost due to COVID-19 in these countries alone. 

"From a public health standpoint, years of life lost is crucial in that it assesses how much life has been cut short for populations affected by the disease," the authors wrote in their paper, published Thursday (Feb. 18) in the journal Scientific Reports.

Related: US life expectancy drops dramatically due to COVID-19

Just a quarter of these lost years of life came from people older than 75. Nearly half of the years of life were lost by people 55 to 75 years old, and nearly a third came from people younger than 55. Among countries where death counts by gender were available, years of life lost were 44% higher in men than women, the authors said.

The study also found that in countries with lots of COVID-19 cases, years of life lost due to COVID-19 were two to nine times higher than years of life lost due to flu during a typical flu season.

The researchers note their study had some important limitations. Given that many countries likely underreport COVID-19 deaths, the researchers' calculation of total years of life lost may be an underestimate. On the other hand, people who die from COVID-19 may tend to have a shorter life expectancy than the average person, which could lead to an overestimate of years of life lost. The study also did not look at years of life lost in all of the 195 countries in the world, meaning the worldwide toll could be even higher.

Finally, the study only examined premature death, and did not look at the potential health burden of the disease among survivors, or "years lived with disability" as a result of the disease. More research is needed on the long-term health effects of COVID-19 and how frequently they occur, they said.

Originally published on Live Science.