High D-Dimer Levels at Presentation in Patients with Venous Thrombosis Is a Marker of Poor Overall and Event Free Survival.
Journal - ASH Annual Meeting Abstracts
The role of D-dimer estimation along with clinical probabilityscoring is well established in the diagnosis of deep venousthrombosis. The issue of predictive value of quantitative D-dimeranalysis to various clinical outcomes are being addressed. Wehave studied here the effect of quantitative D-dimer level atpresentation in patients with deep venous thrombosis on overallsurvival (OS), event free survival (EFS), extent of thrombosisand occurrence of malignancy.
This study included 608 (F: 305; M: 303) consecutive patientsfrom the prospectively maintained database of patients withvenous thrombosis at a University Teaching Hospital, betweenFebruary 2001 and May 2005. All patients underwent an Dopplerultrasound examination to confirm the diagnosis and determinethe extent of venous thrombosis. The database was regularlyupdated (6 monthly) using hospital information systems, questionnairesand clinical review. D-dimer assays were done using Bio-Merieuxkit containing mouse monoclonal antibody. Thrombosis recurrencewas always confirmed by Doppler ultrasound examination. AllPatients with thrombosis received standard treatment with lowmolecular weight heparin and Warfarin. OS and EFS were estimatedby the Kaplan-Meier method. For the purpose of EFS analyses,death, thrombosis recurrence, pulmonary embolism and malignancyoccurrence were all considered as events. Cox regression analysiswas subsequently used to explore the independent effect of variablesthat showed a significant influence on OS or EFS by univariateanalysis. P values < 0.05 were considered significant.
Median age at diagnosis was 64yrs (Range: 16–96 yrs) andmedian follow up was 22 months (Range: 0–51 months). MedianD-dimer level at presentation was 2.3 mg/ml (Range: 0.1–46.3mg/ml). 341 (58.3%) patients had above knee thrombosis, 244(41.7%) patients had below knee venous thrombosis and 14 (2.3%)patients had upper limb thrombosis. 132 (22.2%) patients eitherhad or developed malignancy during the study period. Recurrenceof thrombosis was observed in 28 patients (4.6%). Both univariateand multivariate analysis confirmed the independent poor prognosticimpact of age > 60 yrs, D-dimer > 8mg/ml and above kneethrombosis on OS (P = 0.001, 0.007 & 0.045, respectively)and EFS (P = 0.032, 0.008 & 0.003, respectively). D-dimer> 8mg/ml was also associated with occurrence of malignancy(P value: <0.001) and above knee venous thrombosis (P <0.001). Neither elevated D-dimer nor above knee thrombosis werepredictive of recurrence, whereas age < 60 yrs at diagnosiswas associated with increased risk of recurrence of thrombosis(P = 0.006).
Elevated D-dimer at presentation was associated with decreasedevent free survival and overall survival in patients with venousthrombosis. High D-dimer at presentation was a marker for underlyingmalignancy in patients with thrombosis and was also a predictorof extensive thrombosis. Further studies are warranted to ascertain,whether alternative anticoagulation regimens like prolongedanticoagulation or more intensive anticoagulation negates theadverse impact of high D-dimer at presentation in patients withvenous thrombosis.