RESULTS: A retrospective clinical cohort study was performed utilizing the Northwestern Medicine Enterprise Data Warehouse. Our study population was identified as fully vaccinated adults with at least one booster. The primary risk factor of interest was the number of co-morbidities. The primary outcome was the incidence and time to the first positive SARS-CoV-2 molecular test in the Omicron predominant era. Multivariable Cox modeling analyses to determine the hazard of SARS-CoV-2 infection were stratified by calendar time (Period 1: January 1 -June 30, 2022; Period 2: July 1 -December 31, 2022) due to violations in the proportional hazards assumption. In total, 133,191 patients were analyzed. During Period 1, having 3+ comorbidities was associated with increased hazard for breakthrough (HR = 1.16 CI 1.08-1.26). During Period 2 of the study, having 2 comorbidities (HR = 1.45 95% CI 1.26-1.67) and having 3+ comorbidities (HR 1.73, 95% CI 1.51-1.97) were associated with increased hazard for Omicron breakthrough. Older age was associated with decreased hazard in Period 1 of follow-up. Interaction terms for calendar time indicated significant changes in hazard for many factors between the first and second halves of the follow-up period.
CONCLUSIONS: Omicron breakthrough is common with significantly higher risk for our most vulnerable patients with multiple co-morbidities. Age plays an important role in breakthrough infection with the highest incidence among young adults, which may be due to age-related behavioral factors. These findings reflect real-world differences in immunity and exposure risk behaviors for populations vulnerable to COVID-19.
结果:利用西北医药企业数据仓库进行了一项回顾性临床队列研究。我们的研究人群被确定为至少有一个加强剂的完全接种疫苗的成年人。感兴趣的主要风险因素是合并症的数量。主要结果是Omicron主导时代首次SARS-CoV-2分子检测阳性的发生率和时间。多变量Cox建模分析以确定SARS-CoV-2感染的危害按日历时间(第1期:2022年1月1日至6月30日;第2期:2022年7月1日至12月31日)分层,因为违反了比例风险假设。总的来说,分析了133,191例患者。在第1期,有3+合并症与突破风险增加相关(HR=1.16CI1.08-1.26)。在研究的第二阶段,有2种合并症(HR=1.4595%CI1.26-1.67)和有3+合并症(HR1.73,95%CI1.51-1.97)与Omicron突破的危险增加相关.在随访的第1期,年龄较大与风险降低相关。日历时间的相互作用项表明,在随访期的第一半和第二半之间,许多因素的危险发生了显着变化。
结论:Omicron突破是常见的,对于我们最脆弱的患有多种合并症的患者来说,风险明显更高。年龄在突破性感染中起着重要作用,在年轻人中发病率最高。这可能是由于年龄相关的行为因素。这些发现反映了对COVID-19易感人群在免疫和暴露风险行为方面的现实差异。