News from the front: Estimation of excess mortality and life expectancy in the major epicenters of the COVID-19 pandemic in Italy

Existing studies on the mortality impacts of the COVID-19 pandemic commonly rely on national official reports. However, in a pandemic, deaths from COVID-19 can be miscounted due to under-reporting and inaccurate death registration. Official statistics on COVID-19 mortality are sensitive to classification, estimation and reporting practice which are not consistent across countries. Likewise, the reported mortality is often provided at the national level which results in underestimation of the true scale of the human life impact given that the outbreaks are localised.

This study overcomes the problem of under-reporting of COVID-19-related deaths by using all cause daily death registrations data provided by the Italian Statistical Office (ISTAT) from January 1 to April 30, 2020 in comparison with official figures reported by the Civil Protection Department. The study focuses on the five most severely hit provinces in Italy (Bergamo, Brescia, Cremona, Lodi and Piacenza) and Lombardy region. We calculate excess mortality in 2020 compared to the average of the years 2015 to 2019 and estimate life expectancy for the first wave of the epidemic and for the rest of the year 2020. Not only is life expectancy a reliable measure of a country’s health status and development, it also allows us to quantify the impact of COVID-19 on human life.

The estimated excess deaths show significantly higher mortality than COVID-19 official mortality statistics, particularly during the peak of the epidemic and amongst people aged 60 years and over. We find that for the first wave of the epidemic, life expectancy in the five provinces reduced by 5.1 to 7.8 and 3.2 to 5.8 years for men and women, respectively. For annual life expectancy for the year 2020, in a scenario with no harvesting effect i.e. mortality rates resume to an average level of the years 2015-2019 after the end of the first epidemic wave, the years of life lost is equivalent to 2 to 3.5 years for men and 1.1. to 2.5 years for women in the five provinces.

The COVID-19 pandemic posed a substantial impact on population health in Italy as it represents the largest decline in life expectancy after the 1918 influenza pandemic and the Second World War.