We aimed to examine independent predictive factors for the severity and survival of COVID‐19 disease, from routine blood parameters, especially the blood urea nitrogen (BUN)/creatinine (Cr) ratio. A total of 139 patients with COVID‐19 were investigated at Siirt State Hospital. According to the disease severity, the patients were categorized as three groups (moderate: 85, severe: 54, and critical: 20). Then, patients were divided into two groups: nonsevere (moderate) and severe (severe and critical). Demographic, clinical data, and routine blood parameters were analyzed. In multivariate model adjusted for potential confounders BUN/Cr ratio (odds ratio [OR] = 1.70; 95% confidence interval [CI]: 1.20‐2.40; P = .002) and neutrophil to lymphocyte ratio (NLR) (OR = 2.21; 95% CI: 1.20‐4.30; P < .001) were independent predictive factors for disease severity. In multivariate Cox proportional hazard model BUN/Cr ratio (hazard ratio [HR] = 1.02; 95% CI: 1.01‐1.05; P = .030), and NLR (HR = 1.17; 95% CI: 1.06‐1.30; P = .020) were independent predictors for survival of COVID‐19 disease. The optimal thresholds of the BUN/Cr ratio at 33.5 and 51.7 had the superior possibility for severe disease and mortality, area under the curve (AUC) were 0.98 and 0.95, respectively. The optimal thresholds of NLR at 3.27 and 5.72 had a superior possibility for severe disease and mortality, AUC were 0.87 and 0.85, respectively. BUN/Cr and NLR are independent predictors for COVID‐19 patient severity and survival. Routine evaluation of BUN/Cr and NLR can help identify high‐risk cases with COVID‐19.

中文翻译：

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血尿素氮/肌酐比和其他常规血液参数对 COVID-19 患者疾病严重程度和生存的预测价值。

我们的目的是通过常规血液参数，特别是血尿素氮 (BUN)/肌酐 (Cr) 比值，检查 COVID-19 疾病严重程度和生存的独立预测因素。锡尔特州立医院总共对 139 名 COVID-19 患者进行了调查。根据病情严重程度，将患者分为三组（中度：85例，重度：54例，危重症：20例）。然后，患者被分为两组：非严重（中度）和严重（严重和危重）。分析了人口统计学、临床数据和常规血液参数。在针对潜在混杂因素进行调整的多变量模型中，BUN/Cr 比（比值比 [OR] = 1.70；95% 置信区间 [CI]：1.20‐2.40；P  = 0.002）和中性粒细胞与淋巴细胞比率 (NLR)（OR = 2.21； 95% CI：1.20-4.30；P  < .001）是疾病严重程度的独立预测因素。在多变量 Cox 比例风险模型中，BUN/Cr 比（风险比 [HR] = 1.02；95% CI：1.01‐1.05；P  = 0.030）和 NLR（HR = 1.17；95% CI：1.06‐1.30；P  = .020）是 COVID-19 疾病生存的独立预测因子。BUN/Cr比值的最佳阈值为33.5和51.7，发生严重疾病和死亡的可能性较高，曲线下面积（AUC）分别为0.98和0.95。NLR 的最佳阈值为 3.27 和 5.72，出现严重疾病和死亡的可能性较高，AUC 分别为 0.87 和 0.85。BUN/Cr 和 NLR 是 COVID-19 患者严重程度和生存率的独立预测因子。BUN/Cr 和 NLR 的常规评估有助于识别 COVID-19 的高危病例。