Annual All-Cause Mortality Rate in Germany and Japan (2005 to 2022) With Focus on The Covid-19 Pandemic: Hypotheses And Trend Analyses

Abstract

Germany and Japan are highly industrialized countries, which have large and aging populations in common. In 2022, total population sizes were 84.3 million in Germany and 125.0 million in Japan. From 2005 through 2019, both countries present essentially linearly increasing all-cause mortality base line trends, whereby the increase in Japan is twice that in Germany. In Germany the overall mortality odds ratio per year was 1.010, with 95%-confidence interval (1.009, 1.012), while in Japan it was 1.019, (1.018, 1.020). Therefore, in terms of the Covid-19 pandemic, it is interesting how much the annual all-cause mortality rates 2020 to 2022 in Germany and Japan deviate from the trends estimated from the preceding years 2005 to 2019. In Germany, the total number of deaths in 2020 was essentially in line with the previous mortality upward trend [1,2]. The Japanese data have not yet been studied in much detail. In two analyses of life expectancy covering 37 countries [3] and 29 countries [4], Japan was not included. Also, at the time of this writing, for many countries the 2022 figures had not yet been compiled or published, e.g., https://www.mortality. org/, or the excess mortality had only been assessed for the combined years 2020 and 2021 [5], which obscures differences of the excess mortalities in 2020 and 2021. Schöley et al. concluded that ‘even in 2021, registered COVID-19 deaths continued to account for most life expectancy losses’ [4]. However, this claim is premature since COVID-19 as cause of death is subject to considerable artefacts and imponderability [6]. Increased mortality and decreased life expectancy in 2020 to 2022 could well be due to a multitude of other causes.