학술논문

Reduced mortality during the COVID-19 outbreak in Japan, 2020: a two-stage interrupted time-series design.
Document Type
Journal Article
Source
International Journal of Epidemiology. Feb2022, Vol. 51 Issue 1, p75-84. 10p.
Subject
*COVID-19
*COVID-19 pandemic
*AGE groups
*MIDDLE East respiratory syndrome
*MORTALITY
*WEATHER
*TIME series analysis
Language
ISSN
0300-5771
Abstract
Background: Coronavirus disease 2019 (COVID-19) continues to be a major global health burden. This study aims to estimate the all-cause excess mortality occurring in the COVID-19 outbreak in Japan, 2020, by sex and age group.Methods: Daily time series of mortality for the period January 2015-December 2020 in all 47 prefectures of Japan were obtained from the Ministry of Health, Labour and Welfare, Japan. A two-stage interrupted time-series design was used to calculate excess mortality. In the first stage, we estimated excess mortality by prefecture using quasi-Poisson regression models in combination with distributed lag non-linear models, adjusting for seasonal and long-term variations, weather conditions and influenza activity. In the second stage, we used a random-effects multivariate meta-analysis to synthesize prefecture-specific estimates at the nationwide level.Results: In 2020, we estimated an all-cause excess mortality of -20 982 deaths [95% empirical confidence intervals (eCI): -38 367 to -5472] in Japan, which corresponded to a percentage excess of -1.7% (95% eCI: -3.1 to -0.5) relative to the expected value. Reduced deaths were observed for both sexes and in all age groups except those aged <60 and 70-79 years.Conclusions: All-cause mortality during the COVID-19 outbreak in Japan in 2020 was decreased compared with a historical baseline. Further evaluation of cause-specific excess mortality is warranted. [ABSTRACT FROM AUTHOR]