The Coagulopathy Conundrum: Unveiling Hidden Thrombotic Risk in Hospitalized COVID-19 Patients

Ahmet Demir¹, Selin Yılmaz², Murat Kara³, Ebru Tanrıverdi⁴, HAKAN AKSU⁵

Abstract

Background: COVID-19 is associated with a high risk of thromboembolic events, yet real-world data on the predictive markers and incidence across different severity levels remain incomplete. This study aimed to investigate coagulation profiles, risk factors, and clinical outcomes of thrombotic complications in hospitalised COVID-19 patients.
Methods: A prospective observational study was conducted across four tertiary hospitals in Turkey from 2022 to 2024. A total of 732 confirmed COVID-19 patients were enrolled and followed until discharge or death. All patients underwent routine measurements of D-dimer, fibrinogen, platelet count, and CRP. Thrombotic events, including deep vein thrombosis (DVT), pulmonary embolism (PE), and arterial thrombosis, were confirmed via imaging. Logistic regression identified predictors of thrombosis, and Kaplan–Meier analysis assessed the impact on survival.
Results: Thrombotic complications occurred in 137 patients (18.7%), with PE accounting for 58.4% of cases. Patients with D-dimer >1,500 ng/mL had a 3.9-fold increased risk of thrombotic events (OR = 3.92, 95% CI: 2.14–5.99, p < 0.001). Elevated CRP (>100 mg/L) and platelet counts <150×10⁹/L were independently associated with thrombosis (p < 0.01). In-hospital mortality was significantly higher among patients with thrombosis (28.5% vs. 13.9%, p = 0.003). Median time to event was 7.2 days from admission.
Conclusion: Coagulopathy remains a critical and underrecognised complication in hospitalised COVID-19 patients. Early identification using D-dimer and inflammatory markers could guide anticoagulation decisions and reduce mortality. A standardised thrombosis risk algorithm should be integrated into COVID-19 management protocols.