Low normal level of protein C or of antithrombin increases risk for recurrent cardiovascular events

Mediation effect of antithrombin III between chronic renal insufficiency and chronic coronary artery disease in T2DM patients

PURPOSE

The study aimed to investigate the potential effect of Antithrombin III (ATIII) between chronic renal insufficiency and chronic coronary artery disease (chronic CAD) in type 2 diabetes mellitus (T2DM) patients.

METHODS

T2DM patients hospitalized in ZhongDa Hospital from 2013 to 2018 were enrolled. Relationships between renal function, ATIII, and chronic CAD risk were explored using multivariate regression models. Multiplicative and additive interactions were investigated between ATIII and renal function for CAD risk, and the role of ATIII was determined by bootstrap mediation analysis in patients with chronic renal dysfunction.

RESULTS

A total of 4197 patients were included in the study, with a chronic CAD prevalence of 23.02%. Low ATIII level was statistically associated with chronic renal insufficiency and elevated CAD risk even after adjustments (P < 0.05). A positive correlation between renal function and ATIII was demonstrated, and each 1 SD increase in renal function, ATIII increased by 2.947% (2.406-3.488%, P < 0.001) and 0.969% (0.297-1.642%, P < 0.001) in crude and adjusted models respectively. Patients with decreased renal function and ATIII were at the highest chronic CAD risk (OR = 1.51, 95%CI:1.15-1.98, P < 0.05), while no multiplicative and additive interaction effects were significant. Bootstrap mediation analysis estimated that ATIII mediated approximately 4.27% of the effect of chronic renal insufficiency on chronic CAD risk.

CONCLUSION

ATIII may serve as a mediator between chronic renal insufficiency and chronic CAD, providing mechanistic clues for renal-heart association and new insight into clinical therapies.

Changes in hemostasis parameters in nonfatal methicillin-sensitive Staphylococcus aureus bacteremia complicated by endocarditis or thromboembolic events: a prospective gender-age adjusted cohort study

The aim of this study was to examine the changes in hemostasis parameters in endocarditis and thromboembolic events in nonfatal methicillin-sensitive Staphylococcus aureus bacteremia (MS-SAB) - a topic not evaluated previously. In total, 155 patients were recruited and were categorized according to the presence of endocarditis or thromboembolic events with gender-age adjusted controls. Patients who deceased within 90 days or patients not chosen as controls were excluded. SAB management was supervised by an infectious disease specialist. Patients with endocarditis (N = 21), compared to controls (N = 21), presented lower antithrombin III at day 4 (p < 0.05), elevated antithrombin III at day 90 (p < 0.01), prolonged activated partial thromboplastin time at days 4 and 10 (p < 0.05), and enhanced thrombin-antithrombin complex at day 4 (p < 0.01). Thromboembolic events (N = 8), compared to controls (N = 34), significantly increased thrombin-antithrombin complex at day 4 (p < 0.05). In receiver operating characteristic analysis, the changes in these hemostasis parameters at day 4 predicted endocarditis and thromboembolic events (p < 0.05). No differences in hemoglobin, thrombocyte, prothrombin fragment, thrombin time, factor VIII, D-dimer or fibrinogen levels were observed between cases and controls. The results suggest that nonfatal MS-SAB patients present marginal hemostasis parameter changes that, however, may have predictability for endocarditis or thromboembolic events. Larger studies are needed to further assess the connection of hemostasis to complications in SAB.

Systemic blood coagulation activation in acute coronary syndromes

We evaluated systemic alterations to the blood coagulation system that occur during a coronary thrombotic event. Peripheral blood coagulation in patients with acute coronary thrombosis was compared with that in people with stable coronary artery disease (CAD). Blood coagulation and platelet activation at the microvascular injury site were assessed using immunochemistry in 28 non-anticoagulated patients with acute myocardial infarction (AMI) versus 28 stable CAD patients matched for age, sex, risk factors, and medications. AMI was associated with increased maximum rates of thrombin-antithrombin complex generation (by 93.8%; P< .001), thrombin B-chain formation (by 57.1%; P< .001), prothrombin consumption (by 27.9%; P= .012), fibrinogen consumption (by 27.0%; P= .02), factor (f) Va light chain generation (by 44.2%; P= .003), and accelerated fVa inactivation (by 76.1%; P< .001), and with enhanced release of platelet-derived soluble CD40 ligand (by 44.4%; P< .001). FVa heavy chain availability was similar in both groups because of enhanced formation and activated protein C (APC)-mediated destruction. The velocity of coagulant reactions in AMI patients showed positive correlations with interleukin-6. Heparin treatment led to dampening of coagulant reactions with profiles similar to those for stable CAD. AMI-induced systemic activation of blood coagulation markedly modifies the pattern of coagulant reactions at the site of injury in peripheral vessels compared with that in stable CAD patients.

Pathogenetic and prognostic significance of altered coagulation and fibrinolysis in acute lung injury/acute respiratory distress syndrome

OBJECTIVE

The coagulation and inflammatory cascades may be linked in the pathogenesis of acute lung injury and acute respiratory distress syndrome. However, direct evidence for the contribution of abnormalities in coagulation and fibrinolysis proteins to outcomes in patients with acute lung injury/acute respiratory distress syndrome is lacking.

DESIGN

Retrospective measurement of plasma levels of protein C and plasminogen activator inhibitor-1 in plasma samples that were collected prospectively as part of a large multicenter clinical trial. The primary outcome was hospital mortality. To evaluate the potential additive value of abnormalities of these biomarkers, the excess relative risk of death was calculated for each combination of quartiles of protein-C and plasminogen activator inhibitor-1 levels.

SETTING

Ten university medical centers.

PATIENTS

The study included 779 patients from a multicenter clinical trial of a protective ventilatory strategy in acute lung injury/acute respiratory distress syndrome and 99 patients with acute cardiogenic pulmonary edema, as well as ten normal controls.

MEASUREMENTS AND MAIN RESULTS

Compared with plasma from controls and patients with acute cardiogenic pulmonary edema, baseline protein-C levels were low and baseline plasminogen activator inhibitor-1 levels were elevated in acute lung injury/acute respiratory distress syndrome. By multivariate analysis, lower protein C and higher plasminogen activator inhibitor-1 were strong independent predictors of mortality, and ventilator-free and organ-failure-free days. Plasminogen activator inhibitor-1 and protein C had a synergistic interaction for the risk of death.

CONCLUSIONS

Early acute lung injury/acute respiratory distress syndrome is characterized by decreased plasma levels of protein C and increased plasma levels of plasminogen activator inhibitor-1 that are independent risk factors for mortality and adverse clinical outcomes. Measurement of plasminogen activator inhibitor-1 and protein-C levels may be useful to identify those at highest risk of adverse clinical outcomes for the development of new therapies.

Increase of classic and nonclassic cardiovascular risk factors in patients with acromegaly

OBJECTIVE

To evaluate the prevalence of classic and nonclassic cardiovascular risk factors in patients with acromegaly.

METHODS

Sixty-two patients with acromegaly (50 with active disease and 12 with controlled acromegaly) and 36 healthy persons (the control group) underwent measurement of lipids, fasting plasma glucose, homeostasis model assessment of insulin resistance (HOMA-IR) index, Lp(a), high-sensitivity C-reactive protein (hsCRP), homocysteine, and variables primarily related to thrombogenesis (fibrinogen, antithrombin III, protein C, and protein S).

RESULTS

In comparison with control subjects, patients with active acromegaly had significantly higher mean values of fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol, very-low-density lipoprotein (VLDL) cholesterol, triglycerides, Lp(a), HOMA-IR, and fibrinogen as well as lower mean levels of high-density lipoprotein cholesterol and protein S. In both groups, homocysteine, antithrombin III, protein C, and hsCRP levels were similar. Moreover, patients with active acromegaly, in comparison with those who had controlled acromegaly, presented with significantly higher values of fasting plasma glucose, HOMA-IR, triglycerides, VLDL cholesterol, Lp(a), and fibrinogen, whereas hsCRP and protein S were significantly lower. Finally, low levels of high-density lipoprotein cholesterol and protein S as well as elevated values of VLDL cholesterol, triglycerides, HOMA-IR, and fasting plasma glucose were more prevalent in patients with active acromegaly than in the other groups.

CONCLUSION

Our findings demonstrate that, in comparison with control subjects and patients with controlled acromegaly, patients with active acromegaly had a higher frequency of classic and nonclassic cardiovascular risk factors. These findings are potentially very important because acromegaly is associated with a 2- to 3-fold increase in mortality rate, predominantly related to cardiovascular disease.

Thrombophilia-hypofibrinolysis and atherothrombotic cardiovascular disease < or = age 45 years

Thrombophilia-hypofibrinolysis may play an important role in rare premature (< or = age 45 years) arterial occlusive events in atherothrombotic cardiovascular (ATCVD) disease, particularly in normolipidemic patients. Whether thrombophilia-hypofibrinolysis contributed to ATCVD < or = age 45 years was assessed in 78 men and 40 women with 230 ATCVD events (myocardial infarction (MI) [n = 60], coronary artery bypass graft [CABG, n = 33], angioplasty [n = 52], chronic angina [n = 41], ischemic stroke [n = 11], transient ischemic attack [TIA, n = 24], claudication [n = 9]). Cases were compared with healthy normal adult controls (44 men and 76 women). In men, the Factor V Leiden mutation was present in 6/63 (10%) cases versus 0/44 (0%) controls (P = 0.042), Factor VIII was high (>150%) in 16/60 (27%) cases versus 1/42 (2%) controls (P = 0.001), Factor XI was high (>150%) in 9/57 (16%) cases versus 0/42 (0%) controls (P = 0.009), and plasminogen activator inhibitor activity (PAI-Fx) was high (>21.1 U/mL) in 15/63 (24%) cases versus 3/43 (7%) controls (P = 0.023). In women, protein C was low (<73%) in 4/26 (15%) cases versus 0/74 (0%) controls (P = 0.004), and free protein S was low (<66%) in 5/27 (19%) cases versus 2/74 (3%) controls (P = 0.014). In women, Factor XI was high (>150%) in 3/27 (11%) cases versus 1/74 (1%) controls (P = 0.057), and the lupus anticoagulant was present in 9/32 (28%) cases versus 2/51 (4%) controls (P = 0.002). In patients with ATCVD < or = age 45 years, thrombophilias (Factor V Leiden, Factor VIII, Factor XI, protein C and S deficiency, lupus anticoagulant) and hypofibrinolysis (PAI-Fx, Lp[a]) may promote arterial thrombosis, which is synergistic with atherosclerotic endothelial injury.