Early identification of patients with severe COVID-19 at increased risk of in-hospital death: a multicenter case-control study in Wuhan.

Zhou, Wei; Liu, Yisi; Xu, Beibei; Wang, Sa; Li, Shusheng; Liu, Hong; Huang, Ziting; Luo, Yan; Hu, Ming; Wu, Wenjuan; Zhang, Zhanguo; Long, Xin; Zou, Wenbin; Bian, Yi; Zou, Xiaojing; Elliott, Malcolm; Yue, Lanxin; Deng, Huifang; Chen, Hairong; Gao, Xueli; Wu, Ying; Fang, Minghao; Zhang, Boli; Gao, Yue

Background Most evidence regarding the risk factors for early in-hospital mortality in patients with severe COVID-19 focused on laboratory data at the time of hospital admission without adequate adjustment for confounding variables. A multicenter, age-matched, case-control study was therefore designed to explore the dynamic changes in laboratory parameters during the first 10 days after admission and identify early risk indicators for in-hospital mortality in this patient cohort. Methods Demographics and clinical data were extracted from the medical records of 93 pairs of patients who had been admitted to hospital with severe COVID-19. These patients had either been discharged or were deceased by March 3, 2020. Data from days 1, 4, 7, and 10 of hospital admission were compared between survivors and non-survivors. Univariate and multivariate conditional logistic regression analyses were employed to identify early risk indicators of in-hospital death in this cohort. Results On admission, in-hospital mortality was associated with five risk indicators (ORs in descending order): aspartate aminotransferase (AST, >32 U/L) 43.20 (95% CI: 2.63, 710.04); C-reactive protein (CRP) greater than 100 mg/L 13.61 (1.78, 103.941); lymphocyte count lower than 0.6×109/L 9.95 (1.30, 76.42); oxygen index (OI) less than 200 8.23 (1.04, 65.15); and D-dimer over 1 mg/L 8.16 (1.23, 54.34). Sharp increases in D-dimer at day 4, accompanied by decreasing lymphocyte counts, deteriorating OI, and persistent remarkably high CRP concentration were observed among non-survivors during the early stages of hospital admission. Conclusions The potential risk factors of high D-dimer, CRP, AST, low lymphocyte count and OI could help clinicians identify patients at high risk of death early in the hospital admission. This might assist with rationalization of health care resources.