The prevalence of thromboembolic events among COVID-19 patients admitted to a single centre intensive care unit (ICU): an epidemiological study from a Malaysian population.

Introduction: Thromboembolic (TE) complications in COVID-19 patients are rising globally, contributing significantly to mortality, particularly in severe cases. However, their prevalence, characteristics, and impact on mortality in Malaysia remain unclear.

Objectives: This study aimed to determine the prevalence of thromboembolic (TE) events and associated mortality among COVID-19 patients admitted within a single centre intensive care unit (ICU). The proportions of patients with TE events who died, and factors associated with TE events were explored.

Methods: In this retrospective cohort study, patients with PCR confirmed SARS-CoV-2 virus and who received thromboprophylaxis within February 2020-2021 were included. TE event is a combination of venous [(deep vein thrombosis (DVT), pulmonary embolism (PE)] and arterial (myocardial infarction (MI), stroke) thromboembolism.

Results: Mean (SD) age 56.6 (13.7), 63.5% were male, 61.6% Malays, median (IQR) 7 (3-14) days of ICU stay, 64.2%, 53.2% and 20.9% had underlying hypertension, diabetes and obesity respectively. In total, 240 (44.9%) developed TE event. Significantly higher proportions of COVID-19 patients who developed complications of DVT (2.5% vs. 0.2%;  = 0.013), PE (47.5% vs 34.0%;  = 0.006), stroke (12.3% vs. 1.5; <0.001) and MI (16.4% vs. 4.6%; <0.001) died. Predictors of TE events were age [HR 1.01 (95% CI 1.00-1.02)], obesity [HR 1.98 (95% CI 1.51-2.6)], D-dimer [HR 1.01 (95% CI 1.00-1.01)], and duration of ICU stay [HR 0.98 (95% CI 0.97-0.99)].

Conclusion: In severely ill COVID-19 patients, TE complications were common, and patients with DVT, PE, stroke, or MI faced increased mortality, even with thromboprophylaxis. Age, obesity, elevated D-Dimer levels, and longer ICU stays were significant predictors of TE events. Considering these findings, a more aggressive approach, combining thromboprophylaxis with enhanced anti-inflammatory treatments, may be necessary for high-risk COVID-19 ICU patients to reduce TE events and mortality.