Department of Epidemiology, School of Public Health, Tel Aviv University, Tel Aviv, Israel.
Central Bureau of Statistics, Jerusalem, Israel.
Int J Epidemiol. 2022 Jun 13;51(3):727-736. doi: 10.1093/ije/dyac047.
We aimed to build a basic daily mortality curve in Israel based on 20-year data accounting for long-term and annual trends, influenza-like illness (ILI) and climate factors among others, and to use the basic curve to estimate excess mortality during 65 weeks of the COVID-19 pandemic in 2020-2021 stratified by age groups.
Using daily mortality counts for the period 1 January 2000 to 31 December 2019, weekly ILI counts, daily climate and yearly population sizes, we fitted a quasi-Poisson model that included other temporal covariates (a smooth yearly trend, season, day of week) to define a basic mortality curve. Excess mortality was calculated as the difference between the observed and expected deaths on a weekly and periodic level. Analyses were stratified by age group.
Between 23 March 2020 and 28 March 2021, a total of 51 361 deaths were reported in Israel, which was 12% higher than the expected number for the same period (expected 45 756 deaths; 95% prediction interval, 45 325-46 188; excess deaths, 5605). In the same period, the number of COVID-19 deaths was 6135 (12% of all observed deaths), 9.5% larger than the estimated excess mortality. Stratification by age group yielded a heterogeneous age-dependent pattern. Whereas in ages 90+ years (11% excess), 100% of excess mortality was attributed to COVID-19, in ages 70-79 years there was a greater excess (21%) with only 82% attributed to COVID-19. In ages 60-69 and 20-59 years, excess mortality was 14% and 10%, respectively, and the number of COVID-19 deaths was higher than the excess mortality. In ages 0-19 years, we found 19% fewer deaths than expected.
The findings of an age-dependent pattern of excess mortality may be related to indirect pathways in mortality risk, specifically in ages <80 years, and to the implementation of the lockdown policies, specifically in ages 0-19 years with lower deaths than expected.
本研究旨在建立一个基本的日死亡率曲线,该曲线基于 20 年的数据,考虑了长期和年度趋势、流感样疾病(ILI)和气候等因素,并利用基本曲线来估计 2020-2021 年 COVID-19 大流行期间 65 周内各年龄组的超额死亡率。
使用 2000 年 1 月 1 日至 2019 年 12 月 31 日期间的每日死亡率计数、每周 ILI 计数、每日气候和每年人口规模,拟合了一个包含其他时间协变量(平滑的年度趋势、季节、星期几)的拟泊松模型,以定义基本死亡率曲线。超额死亡率定义为每周和周期性水平上观察到的死亡人数与预期死亡人数之间的差异。分析按年龄组分层。
在 2020 年 3 月 23 日至 2021 年 3 月 28 日期间,以色列共报告了 51361 例死亡,比同期预期死亡人数高出 12%(预期死亡人数为 45756 人;95%预测区间为 45325-46188;超额死亡人数为 5605 人)。同期 COVID-19 死亡人数为 6135 人(所有观察到的死亡人数的 12%),比估计的超额死亡率高出 9.5%。按年龄组分层得到了一种不均匀的、年龄相关的模式。在 90 岁以上年龄组(超额 11%)中,COVID-19 导致的超额死亡率为 100%,而在 70-79 岁年龄组中,超额死亡率为 21%,归因于 COVID-19 的比例为 82%。在 60-69 岁和 20-59 岁年龄组中,超额死亡率分别为 14%和 10%,而 COVID-19 死亡人数高于超额死亡率。在 0-19 岁年龄组中,我们发现死亡人数比预期少 19%。
超额死亡率的年龄相关模式的发现可能与死亡率风险的间接途径有关,特别是在<80 岁的年龄组,与封锁政策的实施有关,特别是在 0-19 岁年龄组,死亡人数低于预期。