Supplementary Material for: Risk Factors and Outcomes of Acute Kidney Injury in Critically Ill Patients with Coronavirus Disease 2019

<b><i>Background:</i></b> Coronavirus disease 2019 (COVID-19) has emerged as a major global health threat with a great number of deaths worldwide. Acute kidney injury (AKI) is a common complication in patients admitted to the intensive care unit. We aimed to assess the incidence, risk factors and in-hospital outcomes of AKI in COVID-19 patients admitted to the intensive care unit. <b><i>Methods:</i></b> We conducted a retrospective observational study in the intensive care unit of Tongji Hospital, which was assigned responsibility for the treatments of severe COVID-19 patients by the Wuhan government. AKI was defined and staged based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Mild AKI was defined as stage 1, and severe AKI was defined as stage 2 or stage 3. Logistic regression analysis was used to evaluate AKI risk factors, and Cox proportional hazards model was used to assess the association between AKI and in-hospital mortality. <b><i>Results:</i></b> A total of 119 patients with COVID-19 were included in our study. The median patient age was 70 years (interquartile range, 59–77) and 61.3% were male. Fifty-one (42.8%) patients developed AKI during hospitalization, corresponding to 14.3% in stage 1, 28.6% in stage 2 and 18.5% in stage 3, respectively. Compared to patients without AKI, patients with AKI had a higher proportion of mechanical ventilation mortality and higher in-hospital mortality. A total of 97.1% of patients with severe AKI received mechanical ventilation and in-hospital mortality was up to 79.4%. Severe AKI was independently associated with high in-hospital mortality (OR: 1.82; 95% CI: 1.06–3.13). Logistic regression analysis demonstrated that high serum interleukin-8 (OR: 4.21; 95% CI: 1.23–14.38), interleukin-10 (OR: 3.32; 95% CI: 1.04–10.59) and interleukin-2 receptor (OR: 4.50; 95% CI: 0.73–6.78) were risk factors for severe AKI development. <b><i>Conclusions:</i></b> Severe AKI was associated with high in-hospital mortality, and inflammatory response may play a role in AKI development in critically ill patients with COVID-19.

**背景：** 2019冠状病毒病（COVID-19）已成为全球重大公共卫生威胁，在全球范围内造成大量死亡。急性肾损伤（AKI）是重症监护病房收治患者的常见并发症。本研究旨在评估重症监护病房收治的COVID-19患者中AKI的发生率、危险因素及院内结局。
**方法：** 本研究在武汉市人民政府指定收治重症COVID-19患者的同济医院重症监护病房开展回顾性观察研究。AKI的定义与分期依据改善全球肾脏病预后组织（KDIGO）标准：轻度AKI为1期，重度AKI为2期或3期。采用logistic回归分析评估AKI的危险因素，采用Cox比例风险模型分析AKI与院内死亡率的关联。
**结果：** 本研究共纳入119例COVID-19患者。患者中位年龄为70岁（四分位间距：59~77），其中男性占比61.3%。共有51例（42.8%）患者在住院期间发生AKI，其中1期、2期、3期AKI的占比分别为14.3%、28.6%和18.5%。与未发生AKI的患者相比，发生AKI的患者机械通气比例及院内死亡率更高。重度AKI患者中97.1%接受了机械通气，院内死亡率高达79.4%。重度AKI与较高的院内死亡率独立相关（优势比[OR]：1.82；95%置信区间[CI]：1.06~3.13）。Logistic回归分析显示，血清白细胞介素-8（OR：4.21；95%CI：1.23~14.38）、白细胞介素-10（OR：3.32；95%CI：1.04~10.59）及白细胞介素-2受体（OR：4.50；95%CI：0.73~6.78）水平升高是重度AKI发生的危险因素。
**结论：** 重度AKI与较高的院内死亡率相关，炎症反应可能在重症COVID-19患者的AKI发生发展中发挥作用。