Fibrinogen: associations with cardiovascular events in an outpatient clinic

The association between fibrinogen levels and severity of coronary artery disease and long-term prognosis following percutaneous coronary intervention in patients with type 2 diabetes mellitus

Background

Fibrinogen is a potential risk factor for the prognosis of CAD and is associated with the complexity of CAD. There is limited research specifically investigating the predictive role of fibrinogen in determining the severity of CAD among patients with T2DM, as well as its impact on the prognosis following PCI.

Methods

The study included 675 T2DM patients who underwent PCI at the Third People's Hospital of Chengdu between April 27, 2018, and February 5, 2021, with 540 of them remaining after exclusions. The complexity of CAD was assessed using the SYNTAX score. The primary endpoint of the study was the incidence of MACCEs.

Results

After adjusting for multiple confounding factors, fibrinogen remained a significant independent risk factor for mid/high SYNTAX scores (SYNTAX score > 22, OR 1.184, 95% CI 1.022-1.373, P = 0.025). Additionally, a dose-response relationship between fibrinogen and the risk of complicated CAD was observed (SYNTAX score > 22; nonlinear P = 0.0043). The area under the receiver operating characteristic curve(AUROC) of fibrinogen for predicting mid/high SYNTAX score was 0.610 (95% CI 0.567-0.651, P = 0.0002). The high fibrinogen group (fibrinogen > 3.79 g/L) had a higher incidence of calcified lesions and an elevated trend of more multivessel disease and chronic total occlusion. A total of 116 patients (21.5%) experienced MACCEs during the median follow-up time of 18.5 months. After adjustment, multivariate Cox regression analysis confirmed that fibrinogen (HR, 1.138; 95% CI 1.010-1.284, P = 0.034) remained a significant independent risk factor for MACCEs. The AUROC of fibrinogen for predicting MACCEs was 0.609 (95% CI 0.566-0.650, P = 0.0002). Individuals with high fibrinogen levels (fibrinogen > 4.28 g/L) had a higher incidence of acute myocardial infarction (P < 0.001), MACCEs (P < 0.001), all-cause death (P < 0.001), stroke (P = 0.030), and cardiac death (P = 0.002). Kaplan-Meier analysis revealed a higher incidence of MACCEs in the high fibrinogen group (Log-Rank test: P < 0.001).

Conclusions

Elevated fibrinogen levels were associated with increased coronary anatomical complexity (as quantified by the SYNTAX score) and a higher incidence of MACCEs after PCI in patients with T2DM.

Ex ante inequality of opportunity in health, decomposition and distributional analysis of biomarkers

We use a set of biomarkers to measure inequality of opportunity (IOp) in the risk of major chronic conditions in the UK. Applying a direct ex ante IOp approach, we find that inequalities in biomarkers attributed to circumstances account for a non-trivial part of the total variation. For example, observed circumstances account for 20 % of the total inequalities in our composite measure of multi-system health risk, allostatic load. We propose an extension to the decomposition of ex ante IOp to complement the mean-based approach, analysing the contribution of circumstances across the quantiles of the biomarker distributions. Shapley decompositions show that, for most of the biomarkers, the percentage contribution of socioeconomic circumstances (education and childhood socioeconomic status), relative to differences attributable to age and gender, increase towards the right tail of the biomarker distribution, where health risks are more pronounced.

Relationship between fibrinogen levels and cardiovascular events in patients receiving percutaneous coronary intervention: a large single-center study

Background:

It is currently unclear if fibrinogen is a risk factor for adverse events in patients receiving percutaneous coronary intervention (PCI) or merely serves as a marker of pre-existing comorbidities and other causal factors. We therefore investigated the association between fibrinogen levels and 2-year all-cause mortality, and compared the additional predictive value of adding fibrinogen to a basic model including traditional risk factors in patients receiving contemporary PCI.

Methods:

A total of 6293 patients undergoing PCI with measured baseline fibrinogen levels were enrolled from January to December 2013 in Fuwai Hospital. Patients were divided into three groups according to tertiles of baseline fibrinogen levels: low fibrinogen, <2.98 g/L; medium fibrinogen, 2.98 to 3.58 g/L; and high fibrinogen, ≥3.58 g/L. Independent predictors of 2-year clinical outcomes were determined by multivariate Cox proportional hazards regression modeling. The increased discriminative value of fibrinogen for predicting all-cause mortality was assessed using the C-statistic and integrated discrimination improvement (IDI).

Results:

The 2-year all-cause mortality rate was 1.2%. It was significantly higher in the high fibrinogen compared with the low and medium fibrinogen groups according to Kaplan-Meier analyses (1.7% vs. 0.9% and 1.7% vs. 1.0%, respectively; log-rank, P = 0.022). Fibrinogen was significantly associated with all-cause mortality according to multivariate Cox regression (hazard ratio 1.339, 95% confidence interval: 1.109–1.763, P = 0.005), together with traditional risk factors including age, sex, diabetes mellitus, left ventricular ejection fraction, creatinine clearance, and low-density lipoprotein cholesterol. The area under the curve for all-cause mortality in the basic model including traditional risk factors was 0.776, and this value increased to 0.787 when fibrinogen was added to the model (IDI = 0.003, Z = 0.140, P = 0.889).

Conclusions:

Fibrinogen is associated with 2-year all-cause mortality in patients receiving PCI, but provides no additional information over a model including traditional risk factors.

Fibrinogen in relation to degree and composition of coronary plaque on intravascular ultrasound in patients undergoing coronary angiography

OBJECTIVE

The aim of this study was to provide additional insight into the role of fibrinogen in coronary artery disease by investigating the associations between plasma fibrinogen with both degree and composition of coronary atherosclerosis as determined by virtual histology-intravascular ultrasound.

PATIENTS AND METHODS

In 581 patients undergoing coronary angiography for acute coronary syndrome (ACS) or stable angina pectoris, preprocedural blood samples were drawn for fibrinogen, C-reactive protein (CRP), interleukin-6, and plasminogen activator inhibitor-1 measurements, and virtual histology-intravascular ultrasound of a nonculprit coronary artery was performed. The degree [plaque volume, plaque burden (PB), and lesions with PB≥70%] and the composition of coronary atherosclerotic plaque (fibrous, fibrofatty, dense calcium, necrotic core tissue, and thin-cap fibroatheroma lesions) were assessed.

RESULTS

Fibrinogen showed a tendency toward a positive association with PB [β (95% CI): 2.55 (-0.52-5.61) increase in PB per ln(g/l) fibrinogen, P=0.09], which was driven significantly by an association in the ACS subgroup [β (95% CI): 4.11 (0.01-8.21) increase in PB per ln(g/l) fibrinogen, P=0.049]. Fibrinogen was also related to the presence of lesions with PB 70% or more in both the full cohort [OR (95% CI): 2.27 (1.17-4.43), P=0.016] and ACS patients [OR (95% CI): 2.92 (1.17-7.29), P=0.022]. All associations were independent of established cardiovascular risk factors, but not CRP. Interleukin-6 and plasminogen activator inhibitor-1 did not provide incremental value to fibrinogen when examining the associations with degree of atherosclerosis. Substantial associations with plaque composition were absent.

CONCLUSION

Fibrinogen is associated with degree of coronary atherosclerosis, especially in ACS patients. However, whether this association is independent of CRP might be questioned and needs further investigation.

Prevalence of the fibrinogen beta-chain, angiotensin-converting enzyme and plasminogen activator inhibitor-1 polymorphisms in Costa Rican young adults with thrombotic disease

Thrombotic disease is a multifactorial condition that involves both classical and genetic risk factors. We studied the association between the classical risk factors of hypertension and smoking, and polymorphisms on the genes of the angiotensin-converting enzyme (ACE), the beta-chain of fibrinogen (FG), and the plasminogen activator inhibitor-1 (PAI-1) in patients with venous and arterial thrombosis. The present investigation is a retrospective case-control study. A total of 340 participants were analyzed, including 162 patients and 178 healthy controls. Hypertension and smoking showed a significant association with thrombotic disease (p < 0.05) but FG level was found significant risk factor only for the venous thrombosis (VT) group (p < 0.04). Significant differences between thrombotic groups were found for the studied polymorphisms of PAI-1 (p < 0.0014), but for both FG beta-chain gene polymorphisms, none of the molecular analyses showed a positive sample for any mutating allele (p > 0.05). For the ACE polymorphism, the I allele present a protective effect in the general thrombotic group. This is one of the first reports in a Latin-American population dealing with these molecular markers and thrombotic diseases.

Antioxidant status in patients with acute myocardial infarction

Free radicals play an important role in the pathogenesis of tissue damage in many clinical disorders, including atherosclerosis. Antioxidants protect the body from damage caused by free radicals. In this study we investigated oxidative stress, antioxidants and inflammatory molecules in patients with acute myocardial infarction. This study has been carried out on 106 patients with acute myocardial infarction, (89 men and 17 females). The control group consisted of 50 healthy, age-matched subjects (40 men and 10 females). Levels of Glucose, lipid profile, glutathione reduced, glutathione peroxidase, Superoxide dismutase, Glycosylated hemoglobin, fibrinogen, vitamin C, vitamin E, malondialdehyde, ceruloplasmin, adenosine deaminase, lysozyme and sialic acid were measured. Malondialdehyde and ceruloplasmin levels were significantly high and antioxidants such as vitamin C, vitamin E, glutathione reduced, glutathione peroxidase and superoxide dismutase were significantly decreased in diabetic and non-diabetic AMI patients as compared with control (p<0.001). Inflammatory markers showed significant rise in diabetic patients as compared with controls. Our results clearly show increased inflammation and oxidative stress in patients with acute myocardial infarction. Depression of antioxidant system in these patients confirms this conclusion.

A new immune resonance scattering spectral assay for trace fibrinogen with gold nanoparticle label

Gold nanoparticles in size of 9.0 nm was prepared by the trisodium citrate and used to label goat anti-human fibrinogen. In the pH 6.2 buffer solution and in the presence of polyethylene glycol (PEG), the immune reaction between gold-labeled goat anti-human fibrinogen and fibrinogen took place and the labeled gold nanoparticles were released from the goat anti-human fibrinogen, and the released gold particles aggregated which leaded the resonance scattering intensity at 560 nm (I560 nm) to enhance greatly. The I560 nm is proportional to the fibrinogen concentration in the range from 0.027 to 1.07 microg mL(-1). The detection limit is 1.14 ng mL(-1). This simple assay was applied to determination of fibrinogen in human plasma, with satisfactory results.

Asymptomatic carotid lesions and aging: Role of hypertension and other traditional and emerging risk factors

BACKGROUND

We evaluated the prevalence of intima-media thickening (IMT) and asymptomatic carotid plaque (ACP) in a group of subjects with or without traditional and/or emerging risk factors (RF).

METHODS

There were 631 subjects (313 male and 318 female) aged between 19 and 97 years, asymptomatic for cerebro- and cardiovascular diseases. The following measurements were used: anamnesis, physical examination, height and sitting blood pressure. Biochemistry variables were also considered: total cholesterol, HDL-C, LDL-C, triglycerides, fibrinogen, high sensitive C-reactive protein, IgG antibodies for Helicobacter pylori (HP), cytotoxic HP, cytomegalovirus and Chlamydia pneumoniae. Finally, an echo color Doppler examination of the carotid arteries was performed. We subdivided the population studied in normotensive and hypertensive subjects and evaluated in each group the frequency of IMT and ACP in relation to age.

RESULTS

We showed that IMT + ACP was significantly more frequent in patients >65 years in comparison with those <65 years (80.6 vs. 52.1%, p < 0.005) and in hypertensive patients in comparison to normotensive, independent of coexistence of other cardiovascular risk factors (71 vs. 48%, p < 0.005). Another interesting result of our study is a significant presence of IMT and ACP in subjects with emerging but without traditional RF than in subjects with traditional but without emerging RF.

CONCLUSIONS

IMT and ACP of carotid arteries are significantly more frequent in patients >65 years vs. those <65 years and in hypertensive patients in comparison to controls. Finally, we have found that the seropositivity of infection and the presence of higher levels of marker of inflammation were correlated with carotid lesion.

Increased plasma fibrinogen predicts one-year mortality in patients with acute ischemic stroke

BACKGROUND AND PURPOSE

Increased plasma fibrinogen is a risk factor for vascular diseases related to atherosclerosis. Its long-term predictive value in stroke survivors is not established. We conducted this study to establish the significance of hyperfibrinogenemia as the possible predictor of 30-day and one-year mortality in patients with acute ischemic stroke.

METHODS

We studied 900 unselected patients with ischemic stroke admitted to the hospital within 24 h after onset of symptoms. We noted demographic data, risk factors for stroke, neurological deficit and disturbances of consciousness on admission. We measured plasma concentration of fibrinogen and the body temperature on day 1 and registered vital status at 1, 3, 6 and 12 months after stroke.

RESULTS

Mean concentration of plasma fibrinogen was 2.9 g/L and 25.2% of patients had increased plasma concentration of fibrinogen (i.e. > or = 3.5 g/L) on day 1. Patients with hyperfibrinogenemia were more likely to die after 1, 3, 6 and 12 months than those with normal plasma fibrinogen (21.1% vs. 15.6%, 36.4% vs. 24.6%, 42.6% vs. 27.3%, 45.7% vs. 31.2%, respectively; P < 0.001 for the last three differences). Hyperfibrinogenemia did not predict short-term case-fatality, but increased concentration of plasma fibrinogen was an independent predictor of one-year case-fatality (P = 0.013; OR: 1.69 (95% CI 1.12-2.55)). Other independent predictors of one-year case-fatality were: neurological deficit on admission, age, white blood cell count, and body temperature on day 1.

CONCLUSIONS

Increased concentration of plasma fibrinogen shortly after ischemic stroke independently increases risk of death within one year after stroke.

Effects of exercise training on 5 inflammatory markers associated with cardiovascular risk

BACKGROUND

Cross-sectional studies suggest that regular exercise has anti-inflammatory effects, leading to lower levels of several proatherogenic inflammatory markers. However, this has yet to be confirmed by randomized prospective trials. We performed a randomized controlled trial to assess whether exercise training decreases levels of 5 inflammatory markers linked to future cardiovascular risk: white blood cell count, fibrinogen, C-reactive protein, soluble intercellular adhesion molecule 1, and soluble CD40 ligand.

METHODS

One hundred fifty-two healthy female smokers were randomized to either 12 weeks of exercise training or health education as part of a smoking cessation program. Smoking was held steady for the first 6 weeks, and thereafter, smoking cessation was actively attempted. One hundred four participants completed 6 weeks, and 88 completed 12 weeks. Fitness and circulating inflammatory marker levels were measured at baseline, 6 weeks, and 12 weeks. To avoid potential confounding from changes in smoking exposure during the second 6 weeks of the trial, the primary end point was change in inflammatory marker levels from baseline to 6 weeks. Change in inflammatory markers from baseline to 12 weeks was a secondary end point.

RESULTS

At baseline, greater physical fitness was associated with lower white blood cell, fibrinogen, and C-reactive protein levels, but these associations were not statistically significant after adjusting for body mass index (P > .1 for all). Fitness improved significantly in the exercise group at both 6 and 12 weeks. However, there were no differences in levels of any inflammatory marker between the exercise and control groups at either 6 weeks (primary end point) or 12 weeks (secondary end point) (P > .05 for all comparisons).

CONCLUSION

In female smokers, baseline associations between fitness and inflammatory markers were largely attributable to differences in body fat; regular exercise did not reduce levels of any of the inflammatory markers studied despite a significant improvement in fitness at both 6 and 12 weeks.

Fibrinogen--marker or mediator of vascular disease?

Fibrinogen plays a key role in platelet aggregation, the final step of the coagulation cascade, i.e. the formation of fibrin, and it is a major determinant of plasma viscosity and erythrocyte aggregation. It is both constitutively expressed and inducible during an acute phase reaction. Increased plasma fibrinogen levels are associated with an increased risk of coronary heart disease and myocardial infarction. The question as to whether fibrinogen is only a marker of the inflammatory process involved in atherosclerosis or a mediator, i.e. a pathogenic factor, has not yet been answered. Human in vivo studies do not permit a conclusive answer to this question. If it is a pathogenic factor, fibrinogen lowering would be a therapeutic option. Selective fibrinogen-lowering agents do not exist however. All agents that lower fibrinogen also have other cardiovascular effects such as a decrease in cholesterol or inflammation. Newer information stems from molecular biology. Polymorphisms in the human fibrinogen gene with higher fibrinogen levels do not increase the risk for myocardial infarction. Fibrinogen knockout mice crossed with an atherosclerosis-susceptible strain (apoprotein E null mice) did not show a decreased extent of atherosclerosis despite the absence of fibrinogen, and a mouse strain over-expressing fibrinogen did not show an increased degree of atherosclerosis. Thus, fibrinogen seems to be a marker rather than a mediator of vascular disease, which would make selective fibrinogen lowering a useless preventive or therapeutic strategy.

Exercise-induced changes in coagulation and fibrinolysis in healthy populations and patients with cardiovascular disease

This review highlights the clinical significance of coagulation and fibrinolytic responses, and adaptations in healthy individuals and patients with cardiovascular disease (CVD). Much of the review focuses on indicators of the potential for coagulation and fibrinolysis. The terms 'coagulation potential' and 'fibrinolytic potential' are used frequently, as much of the literature in the area of exercise haemostasis evaluates factors that reflect an increased potential for coagulation, while coagulation per se, may or may not be occurring. Similarly, fibrinolysis is definitively the lysis of inappropriate or excessive blood clot, which may or may not be occurring when the enzymes that stimulate fibrinolysis are activated. Nevertheless, markers of coagulation and fibrinolytic potential are associated with CVD, ischaemic events, and cardiovascular mortality. Additionally, fibrinolytic potential is associated with other established CVD risk factors. Ischaemic events triggered by physical exertion are more likely to occur due to an occlusive thrombus, suggesting the exercise-induced responses related to haemostasis are of clinical significance. The magnitude of increase in coagulation potential, platelet aggregation and fibrinolysis appears to be primarily determined by exercise intensity. Patients with CVD may also have a larger increase in coagulation potential during acute exercise than healthy individuals. Additionally, the magnitude of the fibrinolytic response is largely related to the resting fibrinolytic profile of the individual. In particular, high resting plasminogen activator inhibitor-1 may diminish the magnitude of tissue plasminogen activator response during acute exercise. Therefore, acute responses to exercise may increase the risk of ischaemic event. However, chronic aerobic exercise training may decrease coagulation potential and increase fibrinolytic potential in both healthy individuals and CVD patients. Due to the aforementioned importance of resting fibrinolysis on the fibrinolytic response to exercise, chronic aerobic exercise training may cause favourable adaptations that could contribute to decreased risk for ischaemic event, both at rest and during physical exertion.

Novel cardiovascular risk factors

In addition to the well-established cardiovascular risk factors of elevated total and low-density lipoprotein cholesterol, hypertension, and cigarette smoking, multiple additional factors are suspected culprits in both the development and progression of atherothrombosis. It is key for the clinician to critically review research findings utilizing an organized framework in order to credibly advise the patient with cardiovascular disease or at risk for its development. The current evidence and recommendations regarding the following "novel"or "emerging" risk factors will be reviewed: lipoprotein(a), hyperhomocysteinemia, C-reactive protein, infectious processes, fibrinogen, and microalbuminuria.

Effect of ciprofibrate on lipoproteins, fibrinogen, renal function, and hepatic enzymes

AIM

The action of ciprofibrate in hypertriglyceridemic patients is well established. Not only is ciprofibrate able to alter the lipid profile, but it can also change the values of fibrinogen, C-reactive protein, creatinine, transaminases, gamma-glutamyl transpeptidase and serum alkaline phosphatase. However, previous studies focused on the effect of ciprofibrate in hypertriglyceridemic patients, leaving unanswered the question of whether ciprofibrate exerts the same effect on hyperlipidemic patients with normal triglyceride values. The aim of this study is to answer this question.

METHODS

In this randomized clinical trial, 64 men and women with elevated cholesterol or triglyceride levels were included. Two subgroups were formed according to triglyceride levels: one (36 patients) with elevated triglyceride levels (> 200 mg/dL [2.26 mmol/L]) and another (28 patients) with normal triglyceride levels (< 200 mg/dL [2.26 mmol/l]). After a 6-week period of step 1 diet according to the National Cholesterol Education Program, ciprofibrate (100 mg once daily) was administered for 16 weeks. Primary efficacy points were the changes of lipid parameters (total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, apoproteins A1, B, E and lipoprotein [a], high sensitivity C reactive protein, fibrinogen, glucose, insulin, aspartate transaminase, alanine transaminase, gamma-glutamyl transpeptidase, alkaline phosphatase, urea and creatinine levels in a fasting blood sample before and after treatment with ciprofibrate.

RESULTS

The subgroup with triglyceride < 200 mg/dL (2.26 mmol/L): After the administration of ciprofibrate total cholesterol and low-density lipoprotein cholesterol were reduced by 15% (P < 0.001), and 19% (P < 0.001), respectively, while high-density lipoprotein cholesterol increased by 9% (P = 0.02). Apoproteins B and E levels were reduced by 21% (P < 0.001) and 11% (P = 0.002), respectively. Subgroup with triglyceride > 200 mg/dL (2.26 mmol/L): After the administration of ciprofibrate, no significant change in LDL cholesterol levels was observed. Total cholesterol levels were reduced by 15% (P < 0.001) and high-density lipoprotein cholesterol levels were increased by 13% (P = 0.004). Apoprotein B and apoprotein E levels were reduced by 16% (P < 0.001) and 30% (P < 0.001), respectively. Apoprotein-A1 levels were increased by 5% (P = 0.024). In the whole group of patients, the fibrinogen levels fell by 7% (P = 0.043), and the serum creatinine level increased by 10% (P < 0.001). This rise in serum creatinine was more pronounced in patients with low triglyceride levels (15% vs 5%, P = 0.009). Ciprofibrate decreased C-reactive protein levels by 26% in 44 patients who had C-reactive protein measurements (P < 0.001). gamma-glutamyl transpeptidase activity was similarly decreased (by approximately 40%) in both groups of patients. Alkaline phosphatase activity decreased in both groups, a reduction which was greater in hypertriglyceridemics (20% vs 10%, P = 0.004).

CONCLUSIONS

Ciprofibrate improved some of the vascular risk factors, such as total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, apoproteins A1, B, and E, and fibrinogen levels in both hypertriglyceridemics and normotriglyceridemics. In addition, ciprofibrate raised the serum creatinine and improved the activity of the hepatic enzymes in the plasma in both patient subgroups.

[Prognostic factors in unstable angina with dynamic electrocardiographic changes. Value of fibrinogen]

INTRODUCTION AND OBJECTIVES

The prognosis of unstable angina varies between series depending on the inclusion criteria and management protocol used. The aim of this study was to analyze in-hospital events and their predictors in a homogeneous single-center series of patients with unstable angina.

MATERIAL AND METHODS

A total of 246 patients with the following inclusion criteria were studied: 1) resting anginal pain, 2) transient electrocardiographic changes during anginal pain, 3) normal CK-MB levels and 4) exclusion of postinfarction angina. All patients were treated with aspirin and enoxaparin (1 mg/kg/12 h). Coronary angiography was performed in the case of recurrent angina or ischemia in Bruce I-II stage during the predischarge effort stress test. The variables recorded were risk factors, history of ischemic heart disease, history of coronary surgery, ECG upon admission, and fibrinogen.

RESULTS

During the hospital stay the following events were recorded: 36% recurrent angina, 58% cardiac catheterization, and 5,7% major events (infarction or death). Multivariate analysis found recurrent angina to be more frequent in patients with a history of coronary bypass surgery (p = 0.004. OR = 22; CI 95%, 3-182), ST-segment changes (p = 0.01. OR = 4.7, CI 95%; 1.4-15.9) and higher fibrinogen (p = 0.002. OR = 1,4, CI 95%; 1.1-1.7). Fibrinogen was the only variable related to cardiac catheterization (p = 0,009. OR = 1.3. CI 95%, 1.1-1.6) and major events (p = 0.001. OR = 2.0. CI 95%, 1.4-3.1).

CONCLUSIONS

1) Unstable angina with electrocardiographic changes was associated to a high rate of in-hospital events. 2) Fibrinogen was related to any event, and previous by-pass surgery and ST changes were related to recurrent angina.