Contact activated kallikrein generation is reduced six months after gastric bypass.

BACKGROUND: Prothrombotic and inflammatory variables decrease after obesity surgery. The contact activation system may be a common denominator of these changes. OBJECTIVE: To characterize the contact system before and 6 months after Roux-en-Y gastric bypass (RYGB) and to evaluate associations with changes (post-surgery minus pre-surgery) in metabolic variables. METHODS: Women (n = 42) and men (n = 18) with obesity underwent RYGB, and measures of kallikrein generation, factor XII (FXII), prekallikrein, high molecular weight kininogen (HK), and C1 esterase inhibitor (C1-inh) were determined before and 6 months after surgery. Associations were evaluated using correlation and multivariate regression analyses. RESULTS: After RYGB, the endogenous kallikrein potential (EKP), peak kallikrein generation, FXII, and prekallikrein were reduced, and kallikrein generation lag time was prolonged (all p < 0.0005). Before and after RYGB, absolute values of EKP, lag time, and peak kallikrein generation correlated consistently with contact system proteins (range of correlation coefficients (rS): -0.43 to -0.28 and 0.24 to 0.45 (pre-surgery); -0.43 to -0.30 and 0.28 to 0.50 (post-surgery)). RYGB-associated changes in EKP correlated with C1-inh (rS = -0.29, p = 0.025), but also with triglycerides (rS = 0.34, p = 0.007) and cholesterol (rS = 0.28, p = 0.029), and independently associated with changes in C1-inh (ß = -0.40) and triglycerides (ß = 0.39). Changes in C1-inh associated with reductions in body weight (ß = -0.39) and HbA1c (ß = 0.38). CONCLUSION: The contact system was affected 6 months after RYGB. Absolute values of kallikrein generation before and after RYGB correlated with contact system proteins, whereas changes after RYGB associated with changes in C1-inh and metabolic variables.

Orthognathic Surgery-Induced Fibrinolytic Shutdown Is Amplified by Tranexamic Acid.

PURPOSE: Little is known of the systemic effects of oral and maxillofacial surgery on the hemostatic balance, including the biochemical effects of tranexamic acid (TXA), on fibrin clot lysis. The present study investigated the effects of orthognathic surgery on fibrin lysis, fibrin structure, and D-dimer and evaluated the effect of TXA on these fibrinolytic measures. MATERIALS AND METHODS: The present double-blind, controlled, and randomized, placebo study included patients referred to the Department of Oral and Maxillofacial Surgery at the University Hospital of Southern Denmark-Esbjerg from August 2014 through September 2016. The patients were elective and had a diagnosis of maxillary or mandibular deficiency, either excessive or asymmetric. All patients underwent bimaxillary orthognathic surgery (OS) with or without maxillary segmentation or additional genioplasty. The patients were blindly randomized to treatment with TXA or placebo. The primary predictor variable was OS. The secondary predictor variable was an intravenous dose of 1 g of TXA or equivalent placebo preoperatively. Blood samples were collected before surgery and 5 hours after the initiation of surgery. The primary outcome variable was lysis of fibrin. The fibrin structure properties and D-dimer were secondary outcome measures. The Mann-Whitney U test was used for the within-group comparisons. The Wilcoxon signed rank test was used for the between-group comparisons. RESULTS: The sample included 96 patients; 45 received placebo and 51 received TXA. Fibrin lysis decreased after OS (P < .001). The fibrinolytic shutdown decreased significantly more in the TXA group than in the placebo group (P < .001). OS altered the fibrin structure properties with comparable effects in the 2 groups. D-dimer increased postoperatively but significantly less so in the TXA group than in the control group (P < .001). CONCLUSIONS: OS is associated with fibrinolytic shutdown and alters fibrin structure properties, driving the hemostatic balance in a prothrombotic direction. The fibrinolytic shutdown is significantly amplified by TXA.

Fibrin lysability is associated with central obesity and inflammation in women with polycystic ovary syndrome.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is characterized by increased central fat mass (CFM), hyper-inflammation, and hemostatic alterations; the risk of cardiovascular disease may also be increased. Reduced fibrin lysability is a risk factor for cardiovascular disease. The present study assessed fibrin lysability in women with PCOS and controls of similar age and body mass index. MATERIAL AND METHODS: Ninety women with PCOS and 35 controls of comparable age and body mass index were included. Hemostatic markers (fibrin lysability, fibrinogen, coagulation factor XIII, plasminogen, plasminogen activator inhibitor 1 [PAI-1], plasmin inhibitor, thrombin activatable fibrinolysis inhibitor (TAFI), D-dimer), C-reactive protein (CRP), body mass index, waist-to-hip ratio, CFM determined by Dual-energy X-ray absorptiometry scan, and sex hormones (testosterone estradiol, and sex hormone binding globulin) were determined. RESULTS: TAFI and CRP were higher in women with PCOS, than controls. In women with PCOS, fibrin lysability correlated with CFM, waist-to-hip ratio, CRP, fibrinogen, and all hemostatic variables (P ≤ .004) except TAFI and D-dimer. CFM correlated with fibrinogen, CRP, coagulation factor XIII, waist-to-hip ratio, plasminogen, PAI-1, plasmin inhibitor, and TAFI (P < .02). In controls, fibrin lysability correlated with CFM, fibrinogen, coagulation factor XIII, and plasmin inhibitor (P ≤ .02). CFM correlated with PAI-1, plasmin inhibitor, coagulation factor XIII, fibrinogen, and CRP (P ≤ .05). Stepwise regression analysis revealed that fibrin lysability was associated with CFM, fibrinogen and CRP in women with PCOS (r2  = .46, P ≤ .001), but only with CFM in controls (r2  = .28, P < .001). CONCLUSIONS: Fibrin lysability was comparable in women with PCOS and controls. Fibrin lysability was associated with CFM and hyper-inflammation in women with PCOS, but only with CFM in controls. These findings suggest that obese women with PCOS and augmented inflammation could have an increased risk of cardiovascular disease.

High burden of coronary atherosclerosis in patients with a new diagnosis of type 2 diabetes.

PURPOSE: The purposes of this study were to compare the presence, extent and composition of coronary plaques in asymptomatic patients with newly diagnosed type 2 diabetes to age- and sex-matched controls. METHODS: Patients with newly diagnosed (<1 year) type 2 diabetes ( n = 44) and controls ( n = 44) underwent contrast-enhanced coronary computed tomography angiography. Advanced plaque analysis including total plaque volume and volumes of plaque components (calcified plaque and non-calcified plaque, including low-attenuation [low-density non-calcified plaque]) was performed using validated semi-automated software. RESULTS: Coronary artery calcification was more often seen in patients with type 2 diabetes (66%) versus controls (48%), p < 0.05. Both the absolute volume (median; interquartile range) of low-density non-calcified plaque (7.9 mm3; 0-50.5 mm3 vs 0; 0-34.3 mm3, p < 0.05) and the increase in low-density non-calcified plaque ratio in relation to total plaque volume ( τ = 0.5, p < 0.001) were significantly higher in patients with type 2 diabetes. More patients with type 2 diabetes had spotty calcification (31% vs 0%, p < 0.05). By multivariate analysis, the presence of any low-density non-calcified plaque was higher in males (odds ratio: 4.06, p < 0.05), who also demonstrated a larger low-density non-calcified plaque volume ( p < 0.001). The presence and extent of low-density non-calcified plaque increased with age, smoking, hypertension and hyperglycaemia, all p < 0.05. CONCLUSION: Asymptomatic patients with newly diagnosed type 2 diabetes had plaque features associated with increased vulnerability as compared with age- and sex-matched controls.

von Willebrand Factor and Prekallikrein in Plasma Are Associated With Thrombus Volume in Abdominal Aortic Aneurysms.

OBJECTIVES: Disruption of the endothelial lining may be one of the events linking intraluminal thrombus and abdominal aortic aneurysm growth. In the present study, we examined whether von Willebrand factor activity in plasma, contact proteins of blood coagulation, and inflammatory biomarkers may be associated with intraluminal thrombus volume in search of a biochemical marker of endothelial damage and thrombus size. DESIGN: Prospective study, correlating potential endothelial biomarkers and intraluminal thrombus volume acquired by computed tomography angiography. MATERIALS AND METHODS: Plasma was consecutively obtained from 38 patients with asymptomatic infrarenal abdominal aortic aneurysm. von Willebrand factor activity, thrombin generation time, factor XII, and prekallikrein concentration were measured in plasma on automated and in-house platforms. In total, 8 patients were excluded due to ongoing anticoagulant therapy, renal impairment, or nonappearance, thus leaving 30 patients for further analysis. All patients had computed tomography angiography, and intraluminal volume was quantified off-line by OsiriX 6.5. RESULTS: Median intraluminal thrombus volume was 42.7 mL. Spearman correlation analysis revealed a positive correlation between thrombus volume, von Willebrand factor activity (ρ = 0.56, P = .0013), and prekallikrein concentration in plasma (ρ = 0.54, P = .002). CONCLUSION: von Willebrand factor activity and concentration of prekallikrein may both be of importance regarding the evolution of thrombus in abdominal aortic aneurysm and possible biomarkers for aneurysm growth.

Similar cardiovascular risk factor profile in screen-detected and known type 2 diabetic subjects.

OBJECTIVE. To compare the cardiovascular disease (CVD) risk factor profile in subjects with screen-detected type 2 diabetes (SDM) and subjects with known type 2 diabetes (KDM). DESIGN. Population-based, cross-sectional survey. SETTING AND SUBJECTS. In a single, semi-rural general practice 2082 subjects were between 20 and 69 years. Of those, 1970 subjects were invited, and a total of 1374 (69.7%) subjects were examined by blood tests, anthropometric measures, and self-administered questionnaires. RESULTS. Before the survey 19 persons were known to have type 2 diabetes. The screening revealed another 31 individuals with type 2 diabetes, diagnosed according to the 1999 World Health Organization criteria. Age, levels of blood pressure, BMI, and dyslipidaemia, and markers of haemostasis and inflammation were comparable in the two groups. Median age in the KDM group was 58 vs. 57 years in the SDM group, p = 0.82, 79% were male vs. 61%, p = 0.23. In both groups 74% had blood pressure ≥ 130/85 mmHg, p = 1.00. In both groups 90% had BMI ≥ 25, p = 1.00, and about half in both groups had BMI ≥ 30, p = 0.56. In the KDM group 63% had dyslipidaemia (low HDL cholesterol or elevated triglycerides) vs. 80% in the SDM group, p = 0.32. Median levels of plasminogen-activator-inhibitor (PAI-1), tissue plasminogen activator (t-PA), as well as fibrinogen and C-reactive protein (CRP) were without statistically significant differences in the two groups, p > 0.1. In contrast, in markers of glycaemic regulation statistically significant differences were found between groups. Median HbA1 was 8.0 vs. 6.5, p < 0.001. Median fasting whole blood glucose level was 8.8 mmol/L vs. 6.3 mmol/L, p < 0.001, and glucose at two hours during OGTT was 16.9 mmol/L vs. 11.2 mmol/L, p < 0.001. Median fasting serum insulin level was 52 pmol/L vs. 80 pmol/L, p = 0.039 and at two hours 127 pmol/L vs. 479 pmol/L, p < 0.001. CONCLUSIONS. The CVD risk-factor profile of SDM patients was similar to the expected adverse profile of patients with KDM. This indicates an already increased risk of cardiovascular disease in diabetic patients before the diabetes becomes clinically manifest, supporting the need for early diagnosis.