Asymptomatic deep venous thrombosis in hospitalized acutely ill medical patients: risk factors and therapeutic implications

Background: Acutely ill medical patients experience deep venous thrombosis (DVT) during the hospitalization, however the time course of DVT is still unclear. Objectives: To evaluate risk factors in acutely ill hospitalized medical patients for asymptomatic DVT (ADVT) and symptomatic DVT (SDVT) within 48 hours from admission and at discharge and comparing prophylaxis treatment with (group A) and without (group B) low-molecular weight heparin (LMWH) Patients/Methods: Consecutive acutely ill medical patients underwent duplex color compression ultrasonography (CUS) of proximal lower limb veins within 48 hours from admission and at discharge to screen for ADVT and to document SDVT. Primary end-point of the multicentric study was the incidence of all DVT. Biographical characteristics at hospitalization, D-Dimer and DD-improve score at entry and at discharge were analyzed by univariate and multivariate analysis to identify variables associated with DVT and compared between groups. Results: : Of 2,100 patients (1002 females, 998 males, age 71±16) included 58 (2.7%) (31 females. 27 males, age 77±14) had ADVT at admission. A binary logistic regression analysis showed that age (O.R.: 1.03, 95% C.I. 1.007-1.05, p=0.008), thrombophilia (O.R.: 10,95% C.I. 3-34, p<0.001) and active cancer (O.R.: 2.3, 95% C.I. 1.3-4.1, p=0.005) were independently associated with ADVT at admission. The median length of hospitalization was 10 days [interquartile range: 6-15 days]. During the hospital stay, 6 patients (0.3%) with a negative CUS at admission experienced DVT (2 SDVT and 4 ADVT). Risk factors were not different on admission of all patients and of patients with DVT (n=64) and when compared to discharge. In the subgroup of patients (n=1118), in whom that performed D-dimer was measured at admission, elevated D-Dimer and higher IMPROVE-DD score were associated with ADVT at admission (n=37) and with all DVT (n=42) at discharge. Patients of group A presented the following risk factors compared to patients of group B: older age, reduced mobility, acute infection, kidney failure, heart or respiratory failure, previous myocardial infarction or stroke and hypertension. Conclusions: : The incidence of ADVT and of SDVT was high (3%) upon admission of acutely ill medical patients upon hospitalization. Advanced age, active cancer, thrombophilia, elevated D-dimer and IMPROVE-DD score greater than 2.5 were risk factors for ADVT should analyzed upon hospitalization for decision of treatment with LMWH. The benefit of therapeutic dose of anticoagulation needs to be investigated in patients with ADVT and specific risk factors. Trial registration: NCT03157843