Challenges in venous thromboembolism prophylaxis: a narrative review of East and Southeast Asian perspectives

Anticoagulant prophylaxis for high-risk patients is strongly recommended in standard clinical practice guidelines worldwide. However, there is a recognized gap between these international mandates and actual practice in East and Southeast Asia. This narrative review summarizes the underlying factors contributing to this underutilization of venous thromboembolism (VTE) thromboprophylaxis among countries in this region. Firstly, the baseline VTE incidence in general Asian population is lower than that of Western population. While historical VTE rates after major orthopedic surgery in Asia aligned with those reported in the West, recent data demonstrate that absolute event rates have decreased significantly following the adoption of modern surgical techniques, early ambulation and mechanical prophylaxis. Similarly, in general surgery, VTE disease burden is notably lower in Asian cohorts at equivalent Caprini scores compared to Western demographics. Furthermore, while Western VTE risk assessment models are available, they lack rigorous validation and calibration specifically for Asian medical patients. Regarding the safety concern, Asians show higher baseline incidence of spontaneous intracranial hemorrhage and carry a greater risk of major bleeding after warfarin administration at the same intensity. Together, these data shift the risk-benefit ratio of routine pharmacological thromboprophylaxis in Asian patients. Finally, the economic burden of routine anticoagulants for all patients at risk remains high in developing countries. We propose that, as an initial effort, institutions should establish their own consensus-based VTE prevention protocols, prioritizing at least the universal implementation of non-pharmacological prophylaxis. Ultimately, more large-scale research specifically targeting Asians is needed to formulate robust evidence-based regional recommendations.