Covid-19: this is the real impact of the pandemic on life expectancy

The Covid pandemic has triggered an increase, unprecedented in recent times, in the number of deaths worldwide and a visible drop in life expectancy worldwide. In a study conducted in 2021, we had already found that the year 2020 had resulted in significant loss of life expectancy. The effect had been particularly striking in the United States, with a drop of more than two years, and in England and Wales, with a drop of one year.

This time, in a new study just published in Nature Human Behavior, we showed that in 2021 life expectancy rebounded somewhat in most Western European countries, while Eastern Europe and the United States recorded further losses . Everywhere, however, the situation is worse than it would probably have been without the pandemic… Except in Norway, which has regained and even exceeded its 2019 life expectancy.

We knew the outlook for 2021 was mixed. The enthusiasm generated by the deployment of vaccination is indeed tempered by the considerable number of infections caused by theregular emergence of new variants. To assess the impact of these changes, our research team at Leverhulme Center for Demographic Science (from the University of Oxford) and Max Planck Institute for Demographic Research gathered data from 29 countries (mainly European, plus Chile and the United States).

Life expectancy: what are we talking about?

Life expectancy is a measure used to “summarize” a country's mortality pattern for a given year. It is calculated on the basis of deaths from all causes: it therefore does not depend on the accuracy of the recording of Covid-related deaths, and can give a broader picture of how the pandemic has affected mortality.

Life expectancy is not a prediction of how long a baby born today will live. Rather, it is the number of years someone born today could expect to live, if they lived their whole life with the current year's death rates (2021 in the case of our research). This is therefore a snapshot of current mortality conditions, should they continue without improvement or deterioration.

Demographers consider life expectancy to be a very useful summary measure of population mortality because it is comparable between countries and over time. Big swings up or down can tell us that something significant has changed – as it did with Covid. The magnitude of these declines allows us to compare mortality shocks over time and across space.

Eastern Europe and the United States particularly affected

Ranking of countries by decreasing cumulative losses of life expectancy (in months) since 2019. The two levels of arrows indicate the evolution in 2020 (top) and 2021 (bottom). In red the increases, in gray the decreases. We can see that France has almost returned to its 2019 level, to within 1,2 months.
J. Dowd, J. M. Aburto, R. Kashyap, Author provided

First observation: we noticed that the impact of the pandemic on mortality varied much more from one country to another in 2021 than in 2020. Life expectancy decreased in practically all the countries studied in 2020, with the exception of Denmark and Norway. But in 2021, for some countries, life expectancy has improved compared to 2020, while for others it has deteriorated further.

● In Eastern Europe, these new declines are probably explained by a double phenomenon: the region avoided some of the early Covid waves in 2020, which did not allow an initial natural immunization of the population; she then showed a lower use of vaccines when large waves arrived in 2021. Bulgaria is the most extreme example, with a loss of 3,5 years since 2019 (1,5 years in 2020 and another two years in 2021).

● The situation is also bad in the United States, for different reasons. Despite a early deployment of vaccines, they continued to move away from Western Europe with an additional loss of almost three months in 2021 after losing more than two years in 2020. Analysis of epidemiological data highlights that the United States have a rate of use of vaccines and boosters lower than that of other Western countries: which probably explains part of this difference in 2021.

It should also be remembered that life expectancy in the United States lags behind European countries For years. It can be hypothesized that part of this American disadvantage may reflect underlying health vulnerabilities specific to this region, and which have been exacerbated by the Covid pandemic. Thus, while most of the loss of life expectancy can be attributed to confirmed deaths due to Covid, a continuous increase in deaths due to drug overdoses was also recorded.

● England and Wales are somewhere in the middle, gaining 2,1 months in 2021 after losing almost a year in 2020. Even for countries that are doing relatively well, Covid has still derail the trajectory of mortality improvement that one would normally see year after year.

● France, for its part, is one of the eight countries which have experienced a significant rebound: France regained 5 months of life expectancy in 2021 after a loss of 6,2 months in 2020, thus returning to a level close to from that of 2019 (such as Belgium, Switzerland and Sweden). This reflects an improvement in mortality at older ages (almost “normalization”), without the losses at younger ages seen in Eastern Europe and the United States.

Evolution of life expectancy at birth for five countries in 2019, 2020 and 2021.
J. Dowd, J. M. Aburto, R. Kashyap, Author provided

Compare the Covid crisis to major past crises

In general, deaths attributable to Covid have shifted slightly towards younger people in 2021 compared to 2020. This is probably due to better vaccination coverage and more precautions taken in older people.

Indeed, it is the countries which have better vaccination coverage for those over 60 who are doing the best in terms of life expectancy. In the United States, the mortality of people over 80 has thus returned to its pre-pandemic level... but, more generally, life expectancy has deteriorated in the country due to the increase in under-60 mortality.

We also compared recent declines in life expectancy with historic crises that have resulted in significant deaths. It turns out that losses on the scale of those seen during the pandemic had not been recorded since World War II in Western Europe, or since the breakup of the Soviet Union in Eastern Europe. East.

A final significant element emerges from this comparison of the current situation with past crises. The impact of previous flu epidemics can be seen, and it is seen that they were followed by rapid rebounds in life expectancy levels – which quickly returned to previous levels. Clearly, the impact of the Covid is of a different nature: it is greater, and above all it is more persistent over time. Which therefore categorically denies the statement still too commonly heard that “Covid is like the flu”.

How to go further

Since life expectancy estimates require fine data on deaths by age and sex, we were not able to accurately calculate life expectancy for all countries in the world in this study.

We know that countries like Brazil and Mexico suffered significant losses in life expectancy in 2020, and are likely to continue to suffer further losses in 2021. Covid-related mortality in countries like India may never be counted accurately due to data limitations, but we know that the number of deaths was considerable.

Vaccination against Covid has a positive effect on life expectancy. Cylinder/Shutterstock

What are the prospects for recovery in life expectancy in 2022 and beyond? The data and models are still fuzzy. We expect the discrepancies to continue, however, due to country differences in vaccine and booster use, past infections, and public health measures (or lack thereof).

However, several elements are already to be considered, even if their respective impacts are not yet known:

• The consequences of delays in the healthcare usually provided (chronic illnesses, etc.) and the continued pressure on healthcare systems remain to be estimated;
• New variants of SARS-CoV-2 capable of better evading existing immunity are still likely to appear;
• The long-term impact of Covid infections (and consequences of the long Covid) on the health of survivors is a big unknown.

While we hope that mortality returns to pre-pandemic levels (and that life expectancy starts to increase again), the persistence of excess mortality in England et elsewhere in 2022 suggests that we still have not fully overcome the impact of the pandemic on mortality, and that the path to recovery remains uncertain.

Jennifer Beam Dowd, Professor of Demography and Population Health, University of Oxford and Deputy Director, Leverhulme Center for Demographic Science, University of Oxford; Jose Manuel Aburto, Brass Blacker Associate Professor of Demography at LSHTM and Marie Sklodowska-Curie Fellow at Leverhulme Center for Demographic Science, University of Oxford et Ridhi Kashyap, Professor of Demography & Computational Social Science, University of Oxford

This article is republished from The Conversation under Creative Commons license. Read theoriginal article.