Study finds US life expectancy decreased between 2019 and 2020 on a scale not seen in 21 peer countries

In a recent study published in the JAMA Network Open, researchers calculated the changes in the life expectancy of United States (US) residents due to the coronavirus disease 2019 (COVID-19) pandemic between 2019 and 2020 stratified by race and sex. They also compared the outcomes with the corresponding changes in peer nations.

Background

In comparison to other high-income nations, the US entered into the pandemic in a weaker state with higher cause-specific mortality from drug overdose cases, metabolic and cardiac disorders, poor socio-economic conditions, greater resistance to preventive measures, and limited accessibility to healthcare facilities and health infrastructure.

Studies reported substantial COVID-19-associated reductions in life expectancy in the US in 2020, with greater reductions in non-Hispanic and Hispanic Blacks compared to non-Hispanic Whites. Additionally, these provisional data-based studies reported that peer nations did not experience such large reductions in life expectancy as the US; the present study was undertaken to confirm these observations and expand the breadth of inter-nation comparisons.

About the study

In the present cross-sectional study, researchers evaluated the COVID-19-associated alterations in life expectancy in the US between 2019 and 2020 and compared these changes to those of 21 peer nations.

For the analysis, three races constitute most (90%) of the US population viz. Hispanics, non-Hispanic Whites, and non-Hispanic Blacks were considered. The 21 peer nations were: Belgium, Austria, Canada, England, Wales, and Denmark (combined), France, Finland, Germany, Italy, Israel, New Zealand, Netherlands, Norway, Northern Ireland, Portugal, South Korea, Scotland, South Korea, Sweden, Spain, Taiwan, and Switzerland. The main outcomes assessed were life expectancy at birth and credible ranges (CR) based on a 10% level of uncertainty.

Simulations of life tables were carried out based on the national death counts and population estimates of the US and 21 other high-income nations between 2019 and 2020, including the US life expectancy estimates stratified by sex and race. The US official counts were obtained from the National Center for Health Statistics (NCHS). The five-year age-stratified abridged tables were calculated based on the Human Mortality Database (HMD). For each nation, the data was obtained from their central statistical agencies, and the obtained data were analyzed in January 2022.

The life tables were obtained in five steps. First, life tables were generated for the total population of the US for 2018 (one table); male and female populations (two tables); Hispanics, non-Hispanic Blacks, and non-Hispanic Whites (three tables); and the males and females in every racial group (six for calculating the age-specific mortality rates, m_x, for every population group for 2018.

Next, the age-stratified mortality rates for all the 12 population groups for 2018, 2019, and 2020 were calculated with the NCHS mortality counts as the numerator and the mid-year (1 July) population count of the US Census Bureau's Vintage 2020 population estimates in the US Centers for Disease Control and Prevention’s (CDC) WONDER database as the denominator.

Subsequently, the age-stratified mortality rates were used to determine the age-stratified mortality rate ratios (RRs) for 2019 and 2020 compared to 2018. Following this, the RRs were multiplied by m_x in US 2018 life tables for estimating the m_x for 2019 and 2020, which were used to generate the 2019 and 2020 life tables.

Results

Between 2019 and 2020, US life expectancy reduced by an average of 1.9 years (CR, 1.7 to 2.0 years). These reductions were much greater among Hispanics (3.7 years; CR, 3.5 to 3.9 years) and non-Hispanic Blacks (3.2 years; CR, 3.0 to 3.4 years) compared to non-Hispanic Whites (1.4 years; CR, 1.2 to 1.5 years). Additionally, the reductions in life expectancy were greater among males (2.1 years; CR, 2 to 2.3) compared to females (1.5 years; CR, 1.4-1.7)

Among the peer nations, the average reduction in life expectancy was 0.6 years (CR, 0.4 to 0.7 years), 4.5 years greater than the US life expectancy (77 years). The outcomes ranged from a decrease of 1.4 years in Spain to an increase in South Korea, Taiwan, and New Zealand.

The greatest reductions in female life expectancy were detected in Spain (1.3 years), Belgium (1.1 years), and Wales and England combined (1.1 years). The greatest reductions in male life expectancy were detected in Wales and England (1.4 years), Italy (1.3 years), and Spain (1.4 years). Notably, no other high-income nation experienced life expectancy reductions like those observed in the US.

Conclusion

The authors of the present study believe that this study is the first to use the most recently released and official US data instead of provisional data to assess the sex-wise and race-wise changes in US life expectancy between 2019 and 2020 and compare it to peer nations.

The study findings showed that there was a much greater reduction in US life expectancy between 2019 and 2020, disproportionately greater among Hispanics and non-Hispanic Blacks compared to non-Hispanic Whites, indicating the need for prioritizing equitable health policies for all races and the US. The 2021 US mortality rates must be analyzed to determine whether the observed reductions in US life expectancy extend to 2021.

Written by

Pooja Toshniwal Paharia

Dr. based clinical-radiological diagnosis and management of oral lesions and conditions and associated maxillofacial disorders.