Lymphocyte-to-C-Reactive Protein (LCR) Ratio Is Not Accurate to Predict Severity and Mortality in Patients with COVID-19 Admitted to the ED

Abstract

Health care systems worldwide have been battling the ongoing COVID-19 pandemic. Since the beginning of the COVID-19 pandemic, Lymphocytes and CRP have been reported as markers of interest. We chose to investigate the prognostic value of the LCR ratio as a marker of severity and mortality in COVID-19 infection. Between 1 March and 30 April 2020, we conducted a multicenter, retrospective cohort study of patients with moderate and severe coronavirus disease 19 (COVID-19), all of whom were hospitalized after being admitted to the Emergency Department (ED). We conducted our study in six major hospitals of northeast France, one of the outbreak's epicenters in Europe. A total of 1035 patients with COVID-19 were included in our study. Around three-quarters of them (76.2%) presented a moderate form of the disease, while the remaining quarter (23.8%) presented a severe form requiring admission to the ICU. At ED admission, the median LCR was significantly lower in the group presenting severe disease compared to that with moderate disease (versus 6.24 (3.24-12) versus 12.63 ((6.05-31.67)), p < 0.001). However, LCR was neither associated with disease severity (OR: 0.99, CI 95% (0.99-1)), p = 0.476) nor mortality (OR: 0.99, CI 95% (0.99-1)). In the ED, LCR, although modest, with a threshold of 12.63, was a predictive marker for severe forms of COVID-19.

Keywords: C reactive protein; COVID-19; LCR; lymphocytes; mortality; severity.

Figure 1

ROC curve for LCR found at admission, a predictive ratio to determine severe COVID (Moderate vs. Severe COVID = ICU admission). Legend: AUC= Area under curve.

Figure 2

ROC Curve for admission LCR, predictive ratio to determine severe COVID cases (surviving vs. deceased patients). Legend: AUC= area under curve.