October 2007, Vol. 36 No. 10 815 Early DVT—Susanna SS Tan et al 1 Department of Diagnostic Radiology Tan Tock Seng Hospital, Singapore 2 Department of Neurology 3 Department of Neurosurgery 4 Department of Neuroradiology National Neuroscience Institute, Singapore Address for Correspondence: Dr Susanna Tan, Department of Diagnostic Radiology, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433. Email: susanna_tan@ttsh.com.sg Early Deep Vein Thrombosis: Incidence in Asian Stroke Patients Susanna SS Tan, 1 MBBS, FRCR, N Venketasubramanian, 2 MBBS, FRCP (Edin), Peck-Leong Ong, 3 MBBS, FRACS (Neurosurg), Tchoyoson CC Lim, 4 MBBS, FRCR Introduction Deep venous thrombosis (DVT) is part of the spectrum of venous thromboembolism (VTE), with thrombi in the limbs predisposing to pulmonary embolism (PE). Immobility is an important risk factor for VTE, and patients with reduced mobility from a wide variety of causes are particularly vulnerable. 1 In stroke patients, PE is the most common cause of death between the second and fourth weeks. 2 DVT is often asymptomatic; 3 PE may occur without clinical signs. 4 It is therefore important to detect and treat occult DVT. Although the incidence of DVT in stroke patients has been widely studied among Caucasians, its incidence in the Asian population is less well established. It has been thought that the incidence of DVT in Asians, particularly the Chinese, is lower compared to that of Caucasian populations. However, it is now believed that this is either increasing or that the condition had been previously underdiagnosed. 5 To date, there has been a paucity of published data on the incidence of DVT among at-risk groups of Asian patients. Various imaging studies such as venography, impedance plethysmography and radioactive iodine (I 125 ) fibrinogen uptake tests were previously used to detect DVT. DVT can now be easily and non-invasively studied using Doppler ultrasound, the accuracy of which has been established. 6 We undertook a prospective Doppler ultrasound study to investigate the incidence of leg DVT in an Asian population Abstract Introduction: Deep venous thrombosis (DVT) is thought to be less common in Asians than in the Caucasian population. The incidence of asymptomatic DVT in high-risk groups in the Asian population has not been well studied. While DVT incidence among Caucasian stroke patients has been extensively studied and the need for prophylaxis established, the lack of data in Asian patients leaves physicians with no firm basis for adopting prophylactic protocols in the local population. Our aim was to prospectively establish the incidence of early DVT in immobilised stroke patients in a heterogenous Asian population. Materials and Methods: We screened 44 patients with significant hemiplegia from acute stroke. Doppler ultrasound, the currently accepted method of investigation for DVT, was used to study patients on admission and at 1 week post-stroke. While there was no standard prophylactic regime in use, none of the patients received heparin and only 2 were given compression stockings. Results: The incidence of DVT at 1 week was 2.4%. Review at 1 month detected another patient with DVT, bringing the overall incidence at 1 month to 4.8%. This is lower than in Caucasian populations, but is similar to another local study on a different group of high-risk patients. Conclusion: The low incidence of early DVT in hospitalised stroke patients of Asian ethnicity does not justify routine screening for this population. Further research to validate this should ideally include a comparison test for DVT as ultrasound may have inherently lower sensitivity in an asymptomatic population. Ann Acad Med Singapore 2007;36:815-20 Key words: Doppler ultrasound Original Article