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Background Severe coronavirus disease 2019 (COVID‐19) is characterized by an increased risk of thromboembolic events, with evidence of microthrombosis in the lungs of deceased patients. Objectives To investigate the mechanism of microthrombosis in COVID‐19 progression. Patients/Methods We assessed von Willebrand factor (VWF) antigen (VWF:Ag), VWF ristocetin‐cofactor (VWF:RCo), VWF multimers, VWF propeptide (VWFpp), and ADAMTS13 activity in a cross‐sectional study of 50 patients stratified according to their admission to three different intensity of care units: low (requiring high‐flow nasal cannula oxygenation, n = 14), intermediate (requiring continuous positive airway pressure devices, n = 17), and high (requiring mechanical ventilation, n = 19). Results Median VWF:Ag, VWF:RCo, and VWFpp levels were markedly elevated in COVID‐19 patients and increased with intensity of care, with VWF:Ag being 268, 386, and 476 IU/dL; VWF:RCo 216, 334, and 388 IU/dL; and VWFpp 156, 172, and 192 IU/dL in patients at low, intermediate, and high intensity of care, respectively. Conversely, the high‐to‐low molecular‐weight VWF multimers ratios progressively decreased with increasing intensity of care, as well as median ADAMTS13 activity levels, which ranged from 82 IU/dL for patients at low intensity of care to 62 and 55 IU/dL for those at intermediate and high intensity of care. Conclusions We found a significant alteration of the VWF‐ADAMTS13 axis in COVID‐19 patients, with an elevated VWF:Ag to ADAMTS13 activity ratio that was strongly associated with disease severity. Such an imbalance enhances the hypercoagulable state of COVID‐19 patients and their risk of microthrombosis.

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Background: Aging in men is characterized by a progressive decline in levels of anabolic hormones, such as testosterone, insulinlike growth factor 1 (IGF-1), and dehydroepiandrosterone sulfate (DHEA-S). We hypothesized that in older men a parallel age-associated decline in bioavailable testosterone, IGF-1, and DHEA-S secretion is associated with higher mortality independent of potential confounders.Methods: Testosterone, IGF-1, DHEA-S, and demographic features were evaluated in a representative sample of 410 men 65 years and older enrolled in the Aging in the Chianti Area (InCHIANTI) study. A total of 126 men died during the 6-year follow-up. Thresholds for lowestquartile definitions were 70 ng/dL (to convert to nanomoles per liter, multiply by 0.0347) for bioavailable testosterone, 63.9 ng/mL (to convert to nanomoles per liter, multiply by 0.131) for total IGF-1, and 50 µg/dL (to convert to micromoles per liter, multiply by 0.027) for DHEA-S. Men were divided into 4 groups: no hormone in the lowest quartile (reference) and 1, 2, and 3 hor-mones in the lowest quartiles. Kaplan-Meier survival and Cox proportional hazards models adjusted for confounders were used in the analysis.Results: Compared with men with levels of all 3 hormones above the lowest quartiles, having 1, 2, and 3 dysregulated hormones was associated with hazard ratios for mortality of 1.47 (95% confidence interval [CI], 0.88-2.44), 1.85 (95% CI, 1.04-3.30), and 2.29 (95% CI, 1.12-4.68), respectively (test for trend, PϽ.001). In the fully adjusted analysis, only men with 3 anabolic hormone deficiencies had a significant increase in mortality (hazard ratio, 2.44; 95% CI, 1.09-5.46 (test for trend, PϽ.001).Conclusions: Age-associated decline in anabolic hormone levels is a strong independent predictor of mortality in older men. Having multiple hormonal deficiencies rather than a deficiency in a single anabolic hormone is a robust biomarker of health status in older persons.

Diabetes is a risk factor for the development of atherothrombosis and venous thromboembolism (VTE). We investigated whether plasma from patients with type 2 diabetes has an imbalance of pro- versus anti-coagulation resulting in hypercoagulability despite normal conventional coagulation tests. We analyzed blood samples from 60 patients with type 2 diabetes and 60 gender- and age-matched healthy subjects (controls) for the levels of pro- and anti-coagulant factors, for thrombin generation and for the numbers of cell-derived circulating microparticles bearing such pro-coagulant triggers as tissue factor and negatively charged phospholipids. The levels of pro- or anti-coagulants as measured with conventional coagulation tests or single factor measurements were similar to those of the control population. In contrast, the median (range) of the height of the thrombin peak (taken as an index of thrombin generation) was higher in patients [205 nM (126-352)] than controls [151 nM (41-289)], P < 0.001. The median numbers of circulating microparticles were higher for patients [5,041/μl (1,821-13,132)] than for controls [1,753/μl (554-13,308)], P < 0.001 and their values were correlated with the height of the thrombin peak (ρ = 0.66, P < 0.001). In conclusion, plasma from patients with type 2 diabetes possesses an imbalance of pro- versus anti-coagulation resulting in hypercoagulability that can be detected by thrombin generation tests, but not by the measurement of the single pro- or anti-coagulant factors. This hypercoagulability is associated with increased numbers of circulating microparticles bearing endogenous pro-coagulant triggers. These findings might explain the relatively high risk of atherothrombosis and VTE described in these patients.