Mortality in Patients of COVID-19 Infection: Biochemical Markers and its Cut-off Values for Predicting Outcome.

OBJECTIVE

To determine the efficacy and cut-off values of C-reactive protein (CRP), lactate dehydrogenase (LDH), serum ferritin, and D-dimer for predicting mortality of COVID-19 infection.

STUDY DESIGN

Observational study.

PLACE AND DURATION OF STUDY

Department of Medicine, Jinnah Hospital, Lahore from January to May 2021.

METHODOLOGY

Serum CRP, LDH, ferritin, and D-dimer were measured in patients with moderate to severe COVID-19 infection at admission. Patients were followed for in-hospital disease outcome. ROC curve was used to determine area under curve (AUC) and cut-off values of biomarkers, followed by multi-variate analysis by logistic regression.

RESULTS

In 386 patients, male to female ratio was 1.47/1 (230/156); and mean age was 54.03 ± 16.2 years. Disease was fatal in 135 (35%) patients. AUC for mortality was 0.730 for LDH, 0.737 for CRP, 0.747 for ferritin and 0.758 for D-dimer. Mortality was higher with LDH ≥400 U/ml, Odds Ratio (OR) 5.37 (95% CI 3.01-9.57: p = 0.001), CRP ≥30 ng/L, OR 4.30 (95% CI 2.11-8.74: p = <0.001), serum ferritin ≥200 ng/ml, OR 4.13 (95% CI 1.05-16.2: p = 0.02), and D-dimer ≥400 ng/ml, OR 2.72 (95% CI 1.06-7.01: p = 0.03) with 2 log likelihood of 131.54 for predicting disease outcome with 71.7% accuracy in multi-variate analysis.

CONCLUSION

Elevated serum CRP, LDH, ferritin and D-dimer are associated with higher mortality in patients of COVID-19 infection. Serum CRP ≥30ng/ml, LDH ≥400 U/L, ferritin ≥200 ng/ml and D-dimer ≥400 ng/ml can predict fatal outcome in COVID-19 patients. Key Words: C-reactive protein (CRP), COVID-19 infection, D-dimer, Ferritin, Lactate dehydrogenase (LDH), Mortality.