Little is yet known whether pathogenesis of COVID-19 is different between young and elder patients. Our study aimed to investigate the clinical characteristics and provide predictors of mortality for young adults with severe COVID-19. A total of 77 young adults with confirmed severe COVID-19 were recruited retrospectively at Tongji Hospital. Clinical characteristics, laboratory findings, treatment and outcomes were obtained from electronic medical records. The prognostic effects of variables were analyzed using logistic regression model. In this retrospective cohort, non-survivors showed higher incidence of dyspnea and co-existing laboratory abnormalities, compared with young survivals in severe COVID-19. Multivariate logistic regression analysis showed that lymphopenia, elevated level of d-dimer, hypersensitive cardiac troponin I (hs-CTnI) and high sensitivity C-reactive protein (hs-CRP) were independent predictors of mortality in young adults with severe COVID-19. Further analysis showed that severely young adults with two or more factors abnormalities above would be more prone to death. The similar predictive effect of above four factors had been observed in all-age patients with severe COVID-19. Lymphopenia, elevated level of d-dimer, hs-CTnI and hs-CRP predicted clinical outcomes of young adults with severe COVID-19.

中文翻译：

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严重COVID-19成年人的临床特征和死亡率预测因素：一项回顾性观察研究

尚不清楚年轻患者和老年患者之间COVID-19的发病机制是否不同。我们的研究旨在调查具有严重COVID-19的年轻成年人的临床特征并提供死亡率的预测指标。回顾性地在同济医院招募了77名确诊严重COVID-19的年轻人。临床特征，实验室检查结果，治疗和结果均来自电子病历。使用逻辑回归模型分析变量的预后效果。在此回顾性队列中，与严重COVID-19中的年轻生存相比，非幸存者显示呼吸困难和并存实验室异常的发生率更高。多元logistic回归分析显示，淋巴细胞减少，d-二聚体水平升高，超敏性心肌肌钙蛋白I（hs-CTnI）和高敏C反应蛋白（hs-CRP）是严重COVID-19的年轻成年人死亡率的独立预测因子。进一步的分析表明，具有两个或两个以上因素异常的严重青壮年更容易死亡。在患有重度COVID-19的所有年龄患者中均观察到以上四个因素的相似预测效果。淋巴细胞减少，d-二聚体，hs-CTnI和hs-CRP水平升高可预测患有严重COVID-19的年轻成年人的临床结局。在患有重度COVID-19的所有年龄患者中均观察到以上四个因素的相似预测效果。淋巴细胞减少，d-二聚体，hs-CTnI和hs-CRP水平升高可预测患有严重COVID-19的年轻成年人的临床结局。在患有重度COVID-19的所有年龄患者中均观察到以上四个因素的相似预测效果。淋巴细胞减少，d-二聚体，hs-CTnI和hs-CRP水平升高可预测患有严重COVID-19的年轻成年人的临床结局。