The Mean Unfulfilled Lifespan (MUL): A new indicator of the impact of mortality shocks on the individual lifespan, with application to global 2020 quarterly mortality from COVID-19

Abstract

The impact of COVID-19 on the individual lifespan can be measured by the difference in period life expectancy at birth (PLEB), an intuitive indicator of mortality conditions during a reference period. When mortality conditions are changing rapidly, however, that intuitive interpretation of the PLEB for short reference periods and of its change conflict with the assumptions under which the PLEB is derived. To avoid assumptions about future mortality, I propose measuring instead the Mean Unfulfilled Lifespan (MUL), defined as the average difference between the actual and otherwise expected ages at death in a recent death cohort. For fine-grained tracking of the pandemic, I also provide an empirical shortcut to MUL estimation for small areas or short periods. I estimate quarterly MUL values for the first half of 2020 in 142 national populations and 91 sub-national populations in Italy, Spain and the US. Across countries, the highest quarterly values were reached in the second quarter in Peru (3.90 years) and in Ecuador (4.59 years). Higher quarterly values still were found in New York and New Jersey, where individuals died respectively 5.41 and 5.56 years younger on average than their expected age at death. Using a seven-day rolling window, I estimate the MUL peaked at 7.32 years in Lombardy, 8.96 years in Madrid, and 8.93 years in New York, but reached 12.86 years for the entire month of April in Guayas (Ecuador). These results illustrate how the MUL provides an intuitive metric to track the pandemic without requiring assumptions about future mortality.

Covid-19 Will Reduce US Life Expectancy at Birth by More Than One Year in 2020

“…Among them, the assumption that mortality risks from different causes are independent is unlikely to hold entirely. 9 As individuals dying of Covid-19 might have been more likely to die of other causes than those who survived the risk of Covid-19 mortality, the impact of Covid-19 on LEB should be less than estimated under the assumption of independence and the threshold number of deaths be higher than 273,500. Several underlying conditions are known to increase the risk of death from Covid-19, however, the remaining life expectancy for an average individual dying from Covid-19 and for an average individual of the same age and sex do not appear to be drastically different.…”

Beyond deaths per capita: comparative COVID-19 mortality indicators

“…While this can be done with life-expectancy reductions as well, the value of life expectancy for a short period in a small geographical area becomes difficult to interpret and additional measures might become better suited to express the effect of COVID-19 on longevity. [23][24][25] The ISCDR and life-expectancy reductions are the least data-demanding of the summary indicators of mortality conditions that allow for comparisons across populations, Figure 5 Estimated value of the crude COVID-19 death rate (CCDR), indirectly age-and-sex standardised COVID-19death rate (ISCDR) and directly age-and-sex standardisedCOVID-19 death rate (DSCDR) (in deaths per 1000 person-years), by selected nation and US state. Sources: Ined, Center for Disease Control and Prevention, Registro Civil (Brazil) 26 and authors' calculations (see online supplemental material 4: sensitivity analysis).…”

Beyond Deaths per Capita: Comparative CoViD-19 Mortality Indicators

“…While this can be done with life-expectancy reductions as well, the value of life expectancy for a short period in a small geographical area becomes difficult to interpret and additional measures might become better suited to express the effect of CoViD-19 on longevity. 24 25 26 The ISCDR and life-expectancy reductions are the least data-demanding of the summary indicators of mortality conditions that allow for comparisons across populations, however, and as crude death rates and life expectancy estimates are widely available, the CCDR and life-expectancy reductions readily allow for temporal comparisons with other-cause mortality.…”