IntroductionIncreased FVIII levels are a well established risk factor for deep venous thrombosis (DVT), whose etiopathogenesis is not yet well understood. In this study, we aimed to evaluate the possibility that inflammatory markers and post-thrombotic syndrome (PTS) could contribute to FVIII levels in patients with a history of DVT. Design and MethodsIt is a case-control study that included 68 patients with DVT of the lower limbs 32months after the acute episode, and 67 healthy adults as controls. We evaluated plasma levels of FVIII, VWF, D-dimer and serum levels of CRP, IL-6, IL-8, TNF-α in patients and controls. The presence of PTS was evaluated by the Villalta scale. ResultsPatients with DVT presented higher levels of FVIII, VWF and D-dimer when compared to controls (P≤0.001). Almost 50% of patients presented FVIII levels above 90th percentile. Furthermore, IL-6 (1.19 vs. 0.98pg/mL, P=0.01) and TNF-α (2.27 vs. 1.57pg/mL, P≤0.001) were also higher in patients when compared to controls. In a linear regression multivariate model, VWF and IL-6 levels were independent factors associated with FVIII levels (P≤0.001). FVIII levels were not increased in patients with PTS. Patients with PTS showed higher levels of IL-8 when compared to patients without PTS (23.03 vs. 18.20pg/mL, P=0.04). ConclusionsIn conclusion, we demonstrated that DVT is associated with increased levels of inflammatory and coagulation markers, including FVIII, even a long time after the acute episode. Moreover, IL-6 levels were an independent factor associated with FVIII levels. Finally, PTS seems to be related to inflammatory cytokine IL-8, a proinflammatory and proangiogenic chemokine, but not to FVIII levels.