Supplementary Material for: Nosocomial COVID-19: A Nationwide Spanish Study

Introduction: SARS-CoV-2 is a highly contagious virus, and despite professionals’ best efforts, nosocomial COVID-19 (NC) infections have been reported. This work aimed to describe differences in symptoms and outcomes between patients with NC and community-acquired COVID-19 (CAC) and to identify risk factors for severe outcomes among NC patients. Methods: This is a nationwide, retrospective, multicenter, observational study that analyzed patients hospitalized with confirmed COVID-19 in 150 Spanish hospitals (SEMI-COVID-19 Registry) from March 1, 2020, to April 30, 2021. NC was defined as patients admitted for non-COVID-19 diseases with a positive SARS-CoV-2 test on the fifth day of hospitalization or later. The primary outcome was 30-day in-hospital mortality (IHM). The secondary outcome was other COVID-19-related complications. A multivariable logistic regression analysis was performed. Results: Of the 23,219 patients hospitalized with COVID-19, 1,104 (4.8%) were NC. Compared to CAC patients, NC patients were older (median 76 vs. 69 years; p p p p p p = 0.003), sepsis (aOR: 1.73; 1.33–2.54; p p = 0.028). NC was associated with a higher case fatality rate (39.1% vs. 19.2%) in all age groups. IHM was significantly higher among NC patients (aOR: 2.07; 1.81–2.68; p Conclusions: NC is associated with greater mortality and complications compared to CAC. Hospital strategies to prevent NC must be strengthened.引言：严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）是一种高传染性病毒，尽管医务工作者已尽最大努力，医院获得性新冠肺炎（nosocomial COVID-19, NC）感染仍有报道。本研究旨在对比医院获得性新冠肺炎患者与社区获得性新冠肺炎（community-acquired COVID-19, CAC）患者的临床表现与结局差异，并明确NC患者发生严重结局的危险因素。方法：本研究为一项全国性、回顾性、多中心观察性研究，分析了2020年3月1日至2021年4月30日期间西班牙150家医院（SEMI-COVID-19登记库）收治的确诊新冠肺炎住院患者的临床数据。NC定义为因非新冠肺炎疾病入院，且在住院第5天或更晚的SARS-CoV-2检测结果呈阳性的患者。本研究的主要结局为30天住院死亡率（in-hospital mortality, IHM），次要结局为其他新冠肺炎相关并发症，采用多变量logistic回归分析进行统计学处理。结果：在23219例新冠肺炎住院患者中，1104例（4.8%）为NC患者。与CAC患者相比，NC患者年龄更大（中位年龄76岁 vs 69岁；P<0.001），脓毒症校正优势比（adjusted odds ratio, aOR）为1.73（95%置信区间1.33~2.54；P=0.003），且各年龄组中NC患者的病死率均更高（39.1% vs 19.2%）。NC患者的住院死亡率显著升高（校正优势比2.07，95%置信区间1.81~2.68；P=0.028）。结论：相较于CAC患者，NC患者的死亡率及并发症发生率均更高，需进一步强化医院感染防控策略以预防NC的发生。