Fibrinolysis and von Willebrand factor in Alzheimer's disease and vascular dementia : a case-referent study

Introduction: The importance of vascular risk factors for Alzheimer’s disease (AD) is not settled. Our aim was to compare patients with AD or vascular dementia (VaD) with non-demented subjects with regard to endothelial derived fibrinolytic and hemostatic factors. Materials and methods: In a cross-sectional mono-center case-referent study in Örebro, Sweden, we consecutively included 95 patients with AD and 55 with VaD and 154 non-demented active seniors (AS). Plasma biomarkers including the endothelial derived fibrinolytic factors: mass concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), tPA/PAI-1 complex and von Willebrand factor (vWF), as well as clinical data were analyzed. Results: None of the endothelial derived fibrinolytic markers or vWF differed between AD vs. VaD. In comparison with the AS group, tPA was higher in AD (p=0.001) and VaD (p=0.023) but its inhibitor, PAI-1 mass concentration did not differ significantly; tPA/PAI-1 complex was higher in both VaD (p=0.038) and AD (p=0.005). vWF concentration was lower in the AS group (p<0.001) than in both dementia groups. Conclusion: Thus, endothelial derived fibrinolytic factors, tPA/PAI-1 complex and vWF, discriminated between the reference group of non-demented elderly and the AD and VaD groups, but not between AD and VaD. This suggests similar disturbances for endothelial derived fibrinolytic and hemostatic factors among AD and VaD patients and may reflect shared vascular pathophysiological mechanisms in the dementias

Fibrinolysis and von Willebrand factor in Alzheimer's disease and vascular dementia : a case-referent study

Introduction: The importance of vascular risk factors for Alzheimer’s disease (AD) is not settled. Our aim was to compare patients with AD or vascular dementia (VaD) with non-demented subjects with regard to endothelial derived fibrinolytic and hemostatic factors. Materials and methods: In a cross-sectional mono-center case-referent study in Örebro, Sweden, we consecutively included 95 patients with AD and 55 with VaD and 154 non-demented active seniors (AS). Plasma biomarkers including the endothelial derived fibrinolytic factors: mass concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), tPA/PAI-1 complex and von Willebrand factor (vWF), as well as clinical data were analyzed. Results: None of the endothelial derived fibrinolytic markers or vWF differed between AD vs. VaD. In comparison with the AS group, tPA was higher in AD (p=0.001) and VaD (p=0.023) but its inhibitor, PAI-1 mass concentration did not differ significantly; tPA/PAI-1 complex was higher in both VaD (p=0.038) and AD (p=0.005). vWF concentration was lower in the AS group (p<0.001) than in both dementia groups. Conclusion: Thus, endothelial derived fibrinolytic factors, tPA/PAI-1 complex and vWF, discriminated between the reference group of non-demented elderly and the AD and VaD groups, but not between AD and VaD. This suggests similar disturbances for endothelial derived fibrinolytic and hemostatic factors among AD and VaD patients and may reflect shared vascular pathophysiological mechanisms in the dementias

Fibrinolysis and von Willebrand factor in Alzheimer's disease and vascular dementia : a case-referent study

Introduction: The importance of vascular risk factors for Alzheimer’s disease (AD) is not settled. Our aim was to compare patients with AD or vascular dementia (VaD) with non-demented subjects with regard to endothelial derived fibrinolytic and hemostatic factors. Materials and methods: In a cross-sectional mono-center case-referent study in Örebro, Sweden, we consecutively included 95 patients with AD and 55 with VaD and 154 non-demented active seniors (AS). Plasma biomarkers including the endothelial derived fibrinolytic factors: mass concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), tPA/PAI-1 complex and von Willebrand factor (vWF), as well as clinical data were analyzed. Results: None of the endothelial derived fibrinolytic markers or vWF differed between AD vs. VaD. In comparison with the AS group, tPA was higher in AD (p=0.001) and VaD (p=0.023) but its inhibitor, PAI-1 mass concentration did not differ significantly; tPA/PAI-1 complex was higher in both VaD (p=0.038) and AD (p=0.005). vWF concentration was lower in the AS group (p<0.001) than in both dementia groups. Conclusion: Thus, endothelial derived fibrinolytic factors, tPA/PAI-1 complex and vWF, discriminated between the reference group of non-demented elderly and the AD and VaD groups, but not between AD and VaD. This suggests similar disturbances for endothelial derived fibrinolytic and hemostatic factors among AD and VaD patients and may reflect shared vascular pathophysiological mechanisms in the dementias

Leptin levels are not affected by enalapril treatment after an uncomplicated myocardial infarction, but associate strongly with changes in fibrinolytic variables in men

Leptin, an adipocyte-derived hormone, is involved in the regulation of body weight and is associated with obesity-related complications, notably cardiovascular disease (CVD). A putative link between obesity and CVD could be induction of plasminogen activator inhibitor-1 (PAI-1) synthesis by leptin. In this study, we hypothesized that the beneficial effect of the angiotensin-converting enzyme inhibitor (ACE(i)) enalapril on PAI-1 levels is mediated by effects on leptin levels. The association between leptin and components of the fibrinolytic system was evaluated in a non-prespecified post hoc analysis of a placebo-controlled randomized, double-blind trial where the effect of the ACE(i) enalapril on fibrinolysis was tested. A total of 46 men and 37 women were randomized to treatment with enalapril or placebo after (median 12 months) an uncomplicated myocardial infarction. At baseline, the participants were stable and had no signs of congestive heart failure. Leptin and fibrinolytic variables (mass concentrations of PAI-1, tissue plasminogen activator (tPA) and tPA-PAI complex) were measured at baseline, and after 10 days, 6 months and 12 months. Enalapril treatment did not change leptin levels, which increased significantly during 1 year of follow-up (p = .007). Changes in leptin levels were strongly associated with changes of tPA mass (p = .001), tPA-PAI complex (p = .003) and of PAI-1 (p = .006) in men, but not in women. Leptin levels are not influenced by treatment with an ACE(i). In contrast, leptin associates strongly with changes in fibrinolytic variables notably with a sex difference, which could be of importance for obesity-related CVD

Thrombomodulin as a Marker for Bleeding Complications During Warfarin Treatment

Background: The major adverse effect of warfarin treatment is hemorrhage. Several risk factors for bleeding complications are also risk factors for thromboembolic events, making the clinical decision to initiate or withhold anticoagulant treatment difficult. Specific markers that solely identify patients at high risk of bleeding would have great clinical impact. This study aimed to test if thrombomodulin (TM) concentrations were associated with bleeding complications, cardiovascular events, or mortality in long-term anticoagulant-treated patients. Methods: In a longitudinal cohort study we followed up 719 patients receiving warfarin treatment for a mean duration of 4.2 years. All bleeding complications causing hospitalization were registered and classified. Soluble TM antigen (sTM) concentration in plasma was measured with an enzyme-linked immunosorbent assay method. Results: During the follow-up time, 113 clinically relevant bleeding events and 73 major bleeding events occurred. Increased concentration of sTM was associated with both clinically relevant bleeding and major bleeding events after adjustment for age. In the multivariable models, hazard ratios for the highest tertiles; compared with the lowest were 2.29 (95% confidence interval, 1.35-3.89) and 2.33 (95% confidence interval, 1.21-4.48), respectively. No association between sTM concentration and nonfatal ischemic cardiovascular events or all-cause mortality was found. Conclusions: Increased levels of sTM are associated with bleeding complications during warfarin treatment but not with cardiovascular events or all-cause mortality. Soluble TM antigen concentration has potential as a new specific marker to identify patients at high risk of bleeding during warfarin treatment