Introduction: Identifying risk factors for venous thromboembolism (VTE) is useful in deciding thromboprophylaxis for VTE. A retrospective study had shown an association between hypertension and diabetes mellitus with VTE in our population. The objective of this study was to confirm these findings and to determine if the complete blood count and coagulation tests can also be useful parameters in stratifying VTE patients for prophylaxis.
Methods: This is a gender and age matched prospective case-control study of 45 Doppler's confirmed DVT and 43 apparently healthy controls.
Results: Identified risk factors included history of hypertension, diabetes mellitus, previous DVT, recent surgery, recent trauma, malignancy, sepsis, and immobility. The cases had a significantly lower mean haematocrit (33±7.4% vs 38±4.6%, p<0.001). Though no differences were observed in leucocyte and platelet counts between cases and controls but stratification as leucocytosis vs leucopaenia (P=0.003) and thrombocytosis vs thrombocytopaenia (P=0.045) differed between both groups. Also, the International normalized ratio (INR) was higher in cases (1.1±0.2 vs 1.0±0.1;P=0.001), hypercoagulable state (INR<0.9) and hypocoagulable state (INR>1.2) were observed in 4.4% and 28.9% of cases respectively but not in controls (P <0.001). Also, aPTT>40 seconds was seen in 4.4% vs 4.7% of cases and controls respectively and aPTT< 30 seconds in 22% of cases but not in controls (P =0.004).
Conclusion: Hypertension and diabetes mellitus are identified risk factors not traditionally associated with DVT. These in addition to a complete blood count and coagulation tests can be useful in stratifying patients for prophylaxis in our population and other similar communities.
Keywords: Anaemia; Diabetes mellitus; Hypercoagulable; Hypertension; Hypocoagulable; Race; Thromboprophylaxis.
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