Background Vaccine hesitancy persists alongside concerns about the safety of coronavirus disease 2019 (COVID-19) vaccines. We aimed to examine the effect of COVID-19 vaccination on risk of death among US veterans. Methods We conducted a target trial emulation to estimate and compare risk of death up to 60 days under two COVID-19 vaccination strategies: vaccination within 7 days of enrollment versus no vaccination through follow-up. The study cohort included individuals aged ≥18 years enrolled in the Veterans Health Administration system and eligible to receive a COVID-19 vaccination according to guideline recommendations from 1 March 2021 through 1 July 2021. The outcomes of interest included deaths from any cause and excluding a COVID-19 diagnosis. Observations were cloned to both treatment strategies, censored, and weighted to estimate per-protocol effects. Results We included 3 158 507 veterans. Under the vaccination strategy, 364 993 received vaccine within 7 days. At 60 days, there were 156 deaths per 100 000 veterans under the vaccination strategy versus 185 deaths under the no vaccination strategy, corresponding to an absolute risk difference of −25.9 (95% confidence limit [CL], −59.5 to 2.7) and relative risk of 0.86 (95% CL, .7 to 1.0). When those with a COVID-19 infection in the first 60 days were censored, the absolute risk difference was −20.6 (95% CL, −53.4 to 16.0) with a relative risk of 0.88 (95% CL, .7 to 1.1). Conclusions Vaccination against COVID-19 was associated with a lower but not statistically significantly different risk of death in the first 60 days. These results agree with prior scientific knowledge suggesting vaccination is safe with the potential for substantial health benefits.

中文翻译：

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2019 年冠状病毒病第一剂疫苗接种后的早期死亡率：目标试验模拟

背景 人们对疫苗的犹豫依然存在，同时也对 2019 年冠状病毒病 (COVID-19) 疫苗的安全性感到担忧。我们的目的是研究 COVID-19 疫苗接种对美国退伍军人死亡风险的影响。方法 我们进行了一项目标试验模拟，以估计和比较两种 COVID-19 疫苗接种策略下长达 60 天内的死亡风险：入组后 7 天内接种疫苗与随访期间不接种疫苗。该研究队列包括在退伍军人健康管理系统登记的年龄≥18岁且有资格根据2021年3月1日至2021年7月1日期间的指南建议接种COVID-19疫苗的个人。感兴趣的结果包括任何原因造成的死亡，不包括因死亡引起的死亡。 COVID-19 诊断。观察结果被克隆到两种治疗策略、审查和加权以估计每个方案的效果。结果 我们纳入了 3 158 507 名退伍军人。根据疫苗接种策略，7天内有364 993人接种了疫苗。60 天时，接种疫苗策略下每 10 万名退伍军人有 156 人死亡，而未接种疫苗策略下每 10 万名退伍军人有 185 人死亡，对应的绝对风险差异为 -25.9（95% 置信限 [CL]，-59.5 至 2.7），相对风险差异为风险为 0.86（95% CL，0.7 至 1.0）。当对前 60 天内感染了 COVID-19 的人进行审查时，绝对风险差异为 -20.6（95% CL，-53.4 至 16.0），相对风险为 0.88（95% CL，0.7 至 1.1）。结论 接种 COVID-19 疫苗可降低前 60 天内的死亡风险，但没有统计学差异。这些结果与先前的科学知识相一致，表明疫苗接种是安全的，并且可能带来巨大的健康益处。