Nonesterified fatty acids, albumin, and platelet aggregation

Prognostic value of fibrinogen-to-albumin ratio combined with coronary calcification score in patients with suspected coronary artery disease

OBJECTIVE

The aim of this work was to evaluate the predictive value of FAR combined with CACS for MACCEs.

BACKGROUND

The fibrinogen-albumin-ratio (FAR), a novel biomarker of inflammation, is associated with the severity of coronary artery disease (CAD). Coronary calcification score (CACS) is associated with the severity of coronary stenosis and is closely related to the prognosis of CAD patients. What is the prognostic value of FAR in patients with chest pain, which has not been reported. This study aims to evaluate the relationship between CACS and FAR and their impact on prognosis in patients with suspected CAD.

METHODS

We used information from 12,904 individuals who had coronary computed tomography angiography (CTA) for chest pain and tracked down any significant adverse cardiac and cerebrovascular events (MACCEs). The following formula was used to calculate FAR: fibrinogen (g/L)/albumin (g/L). Patients were separated into groups with greater levels of FAR (FAR-H) and lower levels of FAR (FAR-L) in accordance with the ideal cut-off value of FAR for MACCEs prediction. In addition, patients were divided into three groups based on their CACS scores (CACS ≤ 100, 100 < CACS ≤ 400, and CACS > 400).

RESULTS

4946 patients [62(55-71) years, 64.4% male] were ultimately enrolled in the present study. During follow-up, a total of 234 cases (4.7%) of MACCEs were documented. Linear regression analysis results showed that CACS (R2 = 0.004, Standard β = 0.066, P < 0.001) was positively associated with FAR in patients with chest pain.Compared to ones with FAR-L, FAR-H had an increased risk for MACCEs (adjusted HR 1.371(1.053-1.786) P = 0.019). Multivariate Cox regression showed that age (adjusted HR 1.015 95% CI 1.001-1.028;p = 0.03), FAR (adjusted HR 1.355 95% CI 1.042-1.763;p = 0.023),FBG (adjusted HR 1.043 95% CI 1.006-1.083;p = 0.024) and CACS (adjusted HR 1.470 95% CI 1.250-1.727;p < 0.001) were the independent risk factors for MACCEs. The FAR and CACS significantly improved MACCEs risk stratification, contributing to substantial net reclassification improvement ( NRI 0.122, 95% CI 0.054-0.198, P < 0.001) and integrated discrimination improvement(IDI 0.011, 95% CI 0.006-0.017, P < 0.001).

CONCLUSION

FAR was an independent risk factor for MACCEs. The results showed that CACS was positively associated with FAR in patients with suspected CAD. A higher level of FAR and heavier coronary calcification burden was associated with worse outcomes among patients with suspected CAD. FAR and CACS improved the risk identification of patients with suspected CAD, leading to a significant reclassification of MACCEs.

The Role of Platelets in Hypoglycemia-Induced Cardiovascular Disease: A Review of the Literature

Cardiovascular diseases (CVDs) are the leading cause of death globally as well as the leading cause of mortality and morbidity in type 2 diabetes (T2D) patients. Results from large interventional studies have suggested hyperglycemia and poor glycemic control to be largely responsible for the development of CVDs. However, the association between hypoglycemia and cardiovascular events is also a key pathophysiological factor in the development of CVDs. Hypoglycemia is especially prevalent in T2D patients treated with oral sulfonylurea agents or exogenous insulin, increasing the susceptibility of this population to cardiovascular events. The adverse cardiovascular risk of hypoglycemia can persist even after the blood glucose levels have been normalized. Hypoglycemia may lead to vascular disease through mechanisms such as enhanced coagulation, oxidative stress, vascular inflammation, endothelial dysfunction, and platelet activation. In the following review, we summarize the evidence for the role of hypoglycemia in platelet activation and the subsequent effects this may have on the development of CVD. In addition, we review current evidence for the effectiveness of therapies in reducing the risk of CVDs.

The Interplay between Non-Esterified Fatty Acids and Plasma Zinc and Its Influence on Thrombotic Risk in Obesity and Type 2 Diabetes

Thrombosis is a major comorbidity of obesity and type-2 diabetes mellitus (T2DM). Despite the development of numerous effective treatments and preventative strategies to address thrombotic disease in such individuals, the incidence of thrombotic complications remains high. This suggests that not all the pathophysiological mechanisms underlying these events have been identified or targeted. Non-esterified fatty acids (NEFAs) are increasingly regarded as a nexus between obesity, insulin resistance, and vascular disease. Notably, plasma NEFA levels are consistently elevated in obesity and T2DM and may impact hemostasis in several ways. A potentially unrecognized route of NEFA-mediated thrombotic activity is their ability to disturb Zn²⁺ speciation in the plasma. Zn²⁺ is a potent regulator of coagulation and its availability in the plasma is monitored carefully through buffering by human serum albumin (HSA). The binding of long-chain NEFAs such as palmitate and stearate, however, trigger a conformational change in HSA that reduces its ability to bind Zn²⁺, thus increasing the ion’s availability to bind and activate coagulation proteins. NEFA-mediated perturbation of HSA-Zn²⁺ binding is thus predicted to contribute to the prothrombotic milieu in obesity and T2DM, representing a novel targetable disease mechanism in these disorders.

The Fibrinogen-to-Albumin Ratio Is Associated With Outcomes in Patients With Coronary Artery Disease Who Underwent Percutaneous Coronary Intervention

Coronary artery disease (CAD) is a systemic chronic inflammatory disease, and serum fibrinogen and albumin are 2 important factors in systemic inflammation. We aimed to investigate the relationship between the fibrinogen–albumin ratio (FAR) and outcomes in patients with CAD who underwent percutaneous coronary intervention (PCI). All patients were from the Clinical Outcomes and Risk Factors of Patients with Coronary Heart Disease after PCI (CORFCHD-PCI) study, which is a retrospective cohort study (Identifier: ChiCTR-ORC-16010153) that includes a total of 6050 patients with CAD after PCI from January 2008 to December 2016. A total of 5829 patients with CAD after PCI were recruited in the present study. They were divided into 2 groups according to the FAR cutoff value, which was calculated using a receiver operating characteristic curve, a low group (FAR < 0.095, n = 3811), and a high group (FAR ≥ 0.095, n = 2018). The average follow-up time was 35.9 ± 22.6 months. The multivariate Cox proportional hazards model showed that FAR was independently correlated with all-cause mortality (adjusted hazard ratio [HR] = 1.432 [1.134-1.808], P = .003), cardiac mortality (adjusted HR = 1.579 [1.218-2.047], P = .001), major adverse cardiac and cerebrovascular events (adjusted HR = 1.296 [1.125-1.494], P < .001), major adverse cardiac events (adjusted HR = 1.357 [1.170-1.572], P < .001), and heart failure (adjusted HR = 1.540 [1.135-2.091], P = .006). The present study indicated that the FAR was associated with adverse outcomes in patients with CAD who underwent PCI.

Serum albumin and cardiovascular disease: State-of-the-art review

Cardiovascular disease is the leading cause of death worldwide. Conceptually, endothelial dysfunction, inflammatory conditions and oxidative stress are at the forefront of the onset and development of most cardiovascular diseases, particularly coronary artery disease and heart failure. Serum albumin has many physiological properties, including in particular antioxidant, anti-inflammatory, anticoagulant and anti-platelet aggregation activity. It also plays an essential role in the exchange of fluids across the capillary membrane. Hypoalbuminemia is a powerful prognostic marker in the general population as well as in many disease states. In the more specific context of cardiovascular disease, low serum albumin is independently associated with the development of various deleterious conditions such as coronary artery disease, heart failure, atrial fibrillation, stroke and venous thromboembolism. Low serum albumin has also emerged as a potent prognostic parameter in patients with cardiovascular disease regardless of usual prognostic markers. Remarkably, its potent prognostic value persists after adjusting for causative confounders such as malnutrition and inflammation. This prognostic value probably refers primarily to the syndrome of malnutrition-inflammation and the severity of comorbidities. Nevertheless, several recent meta-analyses strongly support the hypothesis that hypoalbuminemia may act as an unrecognized, potentially modifiable risk factor contributing to the emergence and progression of cardiovascular disease, primarily by exacerbating oxidative stress, inflammation and platelet aggregation, and by favouring peripheral congestion and pulmonary edema. Currently, it is unknown whether prevention and correction of low serum albumin offers a benefit to patients with or at risk for cardiovascular disease, and further studies are critically needed in this setting.

Prognostic Significance of Serum Albumin in Patients With Acute Coronary Syndrome

In patients with unstable angina pectoris (UAP) or non-ST elevation myocardial infarction (NSTEMI), long-term mortality remains high despite improvements in the diagnosis and treatment. In this study, we investigated whether serum albumin level is a useful predictor of long-term mortality in patients with UAP/NSTEMI. Consecutive patients (n = 403) who were hospitalized with a diagnosis of UAP/NSTEMI were included in the study. Patients were divided into 2 groups based on the presence of hypoalbuminemia and the relationship between hypoalbuminemia and mortality was analyzed. Hypoalbuminemia was detected in 34% of the patients. The median follow-up period was 35 months (up to 45 months). Long-term mortality rate was 32% in the hypoalbuminemia group and 8.6% in the group with normal serum albumin levels ( P < .001). On multivariate analysis, hypoalbuminemia, decreased left ventricular ejection fraction, and increased age were found to be independent predictors of mortality ( P < .05). The cutoff value of 3.10 g/dL for serum albumin predicted mortality with a sensitivity of 74% and specificity of 67% (receiver-operating characteristic area under curve: 0.753, 95% CI: 0.685-0.822). All-cause long-term mortality rates were significantly increased in patients with hypoalbuminemia. On-admission albumin level was an independent predictor of mortality in patients with UAP/NSTEMI.

Prognostic nutritional index may not be a good prognostic indicator for acute myocardial infarction

The prognostic nutritional index (PNI) has been applied in acute myocardial infarction (AMI) recently.However, the application of PNI in AMI needs verification. This was a prospective cohort study. Patients diagnosed with AMI were enrolled. PNI was calculated as (serum albumin (SA in g/L)) + (5 × total lymphocyte count (TLC) × 10⁹/L). Modified PNI (mPNI) was analyzed by logistic regression analysis to reset the proportion of SA and TLC. The primary outcome was all-cause death. A total of 598 patients were enrolled; 73 patients died during follow-up. The coefficient of SA and TLC in the mPNI formula was approximately 2:1. The area under the receiver operating characteristic curve of SA, TLC, PNI, mPNI and GRACE in predicting death for patients with AMI was 0.718, 0.540, 0.636, 0.721 and 0.825, respectively. Net reclassification improvement (NRI) between PNI and mPNI was 0.230 (p < 0.001). Integrated discrimination improvement (IDI) was 0.042 (p = 0.001). Decision curve analysis revealed that mPNI had better prognostic value for patients with AMI than PNI; however, it was not superior to SA. Thus, PNI may not a reliable prognostic predictor of AMI; after resetting the formula, the value of PNI in predicting prognosis of AMI is almost entirely due to SA.

Plasma levels of free fatty acids correlate with type 2 diabetes mellitus

AIMS

Free fatty acids (FFA) mediate adverse metabolic effects such as downregulated carbohydrate metabolisms, providing causal links between obesity and the development of type 2 diabetes mellitus (T2DM). Here, we investigated the plasma concentrations of FFA alone and in combination with protein glycation as potential diagnostic and prognostic biomarkers of T2DM.

MATERIALS AND METHODS

EDTA-plasma obtained from 48 newly diagnosed male T2DM patients, 48 long-term controlled (24 male and 24 female) T2DM patients, 20 prediabetic male T2DM patients and two age-matched control cohorts (48 non-diabetic (ND) men; 24 male and 24 female ND partipants) were analysed for a set of clinical parameters including FFA. Glycation sites were quantified after tryptic digestion using tandem mass spectrometry.

RESULTS

Median plasma concentrations of FFA were almost three-fold higher in samples obtained from newly diagnosed (long-term controlled) T2DM patients than in those obtained from the control group, providing diagnostic sensitivity (SN) of 92% (85%) and specificity (SP) of 90% (88%). When combined with the glycation level of lysine-141 of haptoglobin, diagnostic accuracy improved further for newly diagnosed (SN, 94%; SP 96%) and long-term controlled (SN, 85%; SP, 94%) T2DM patients (HbA1c: SN, 88%; SP, 96%). A prospective pilot study evaluating the prognostic value revealed initially low FFA levels for pre-diabetic patients that increased in the following four years in patients whose prediabetic state worsened or who developed T2DM.

CONCLUSIONS

FFA levels are elevated in newly diagnosed and long-term controlled T2DM patients, providing high diagnostic accuracy of 87% and 91%, respectively, which improved further when combined with the glycation degree of lysine-141 in haptoglobin. Additionally, FFA showed higher mean fold-changes than HbA1c or FPG in subjects developing T2DM, indicating higher sensitivity towards the progression of the disease.

Medium-Chain Acylcarnitines Are Associated With Cardioembolic Stroke and Stroke Recurrence

Objective—

Stroke is a heterogeneous disease with diverse causes, which affect the risk of recurrence. This study aimed to identify novel biomarkers that are clinically relevant to the diagnosis of cardioembolic stroke (CE) and the prediction of stroke recurrence using metabolomics.

Approach and Results—

We obtained blood samples and clinical data from a consecutively registered, hospital-based acute stroke registry and from healthy controls. Mass-spectrometry–based profiling was performed, and several metabolomic signatures were selected for the discrimination of CE and stroke recurrence, coupled with multivariate statistical analysis. Finally, 190 acute ischemic stroke participants (43 CE patients and 147 non-CE patients) and 30 control participants were included. We obtained 29 metabolomics signatures, and of these, 2 medium-chain acylcarnitines (decanoylcarnitine and octanoylcarnitine) were selected as independent discriminants for CE (odds ratio, 2.839; 95% CI, 1.241–6.493 for decanoylcarnitine; odds ratio, 2.839; 95% CI, 1.241–6.493 for octanoylcarnitine). Elevated medium-chain acylcarnitines were also associated with a higher risk of stroke recurrence (hazard ratio, 3.767; 95% CI, 1.276–11.117 for decanoylcarnitine; hazard ratio, 5.519; 95% CI, 1.22–18.781 for octanoylcarnitine). The levels of decanoylcarnitine and octanoylcarnitine were correlated as known surrogate markers of CE. The levels of decanoylcarnitine and octanoylcarnitine were significantly higher in stroke patients with a high-risk potential of cardioembolism than in those with low or intermediate risk.

Conclusions—

Metabolomics provided an improved understanding of CE pathogenesis and stroke recurrence. We have identified decanoylcarnitine and octanoylcarnitine as novel biomarkers for CE and stroke recurrence.

Human serum albumin in cardiovascular diseases

Cardiovascular diseases are the leading cause of death worldwide. Endothelial dysfunction, inflammation and oxidative stress are at the forefront in the onset and development of atherosclerosis and many cardiovascular diseases. Epidemiological evidence is that low serum albumin levels are linked to incident ischemic heart disease, heart failure, atrial fibrillation, stroke and venous thromboembolism, independent of risk factors, body mass index and inflammation. Hypoalbuminemia has also emerged as an independent prognosticator in many cardiovascular diseases, such as coronary artery disease, heart failure, congenital heart disease, infective endocarditis and stroke, even after adjusting for usual causal factors and prognostic markers. Given physiological properties of serum albumin that include anti-inflammatory, antioxidant, anticoagulant and antiplatelet aggregation activity as well as colloid osmotic effect, hypoalbuminemia could act as an unrecognized modifiable risk factor. The purpose of this review is to provide an overview of the physiological properties of serum albumin, as well as prevalence, causes, prognostic value and potential contribution to the disease emergence and progression of hypoalbuminemia, and the resulting clinical implications.

[Serum albumin and cardiovascular diseases: A comprehensive review of the literature]

Cardiovascular diseases are the leading cause of death worldwide. Conceptually, endothelial dysfunction, inflammatory status and oxidative stress are at the forefront in the onset and development of most cardiovascular diseases, particularly coronary artery disease and heart failure. Serum albumin, the most abundant plasma protein, has many physiological properties, including anti-inflammatory, antioxidant and antiplatelet aggregation activity. It also plays an essential role in the fluid exchange across the capillary membrane. Definite evidence is that hypo-albuminemia is a powerful prognostic marker in the general population as well as in many pathological settings. In the more specific context of cardiovascular diseases, serum albumin is independently associated with the development of a variety of deleterious conditions such as coronary artery disease, heart failure, atrial fibrillation and stroke. Serum albumin has also emerged as a powerful prognostic parameter in patients with coronary artery disease, heart failure, congenital heart disease, infective endocarditis, cardiovascular surgery and stroke, regardless of usual prognostic markers. This prognostic value probably refers mainly to the malnutrition-inflammation syndrome and the severity of comorbidities. Nevertheless, hypo-albuminemia may act as an unknown and modifiable risk factor that contributes to the emergence and the pejorative evolution of cardiovascular diseases, mainly by exacerbation of inflammation, oxidative stress and platelet aggregation, and by pulmonary and myocardial edema. This article provides an overview of the physiological properties of serum albumin, the prevalence, causes, prognostic value and potential contribution to the emergence and aggravation of cardiovascular disease of hypoalbuminemia, as well as its clinical implications.

Free Fatty Acid Is Associated with Thrombogenicity in Cardioembolic Stroke

Background: Recently, the role of free fatty acids (FFAs) in thromboembolism has re-emerged in the context of cardioembolic stroke. Therefore, we attempted to determine the role of FFAs in embolic risk in various potential sources of cardioembolism (PSCE). We hypothesized that if elevated FFA levels in stroke patients are associated with thrombogenesis, then patients with a well-known high risk of embolic sources would have high FFA levels. Methods: Data collected from 2 hospital-based stroke registries were analyzed to investigate the association between FFA and PSCE. Results: A total of 2,770 acute stroke patients, including 539 with cardioembolic stroke, were selected for analysis. FFA was an independent predictor for cardioembolism (OR 2.755, 95% CI 2.221-3.417, p < 0.001). Among the PSCE, FFA levels were significantly associated with high risk of atrial fibrillation (AF), valvular heart disease, congestive heart failure with low ejection fraction, left atrial thrombus, left ventricular thrombus, left atrial smoke, and ventricular wall motion abnormality. FFA levels increased with the number of PSCE per patient without interaction with the presence of AF. Conclusions: Among acute stroke patients, FFA levels increased in groups with higher risk of cardioembolic stroke irrespective of the presence of AF. These results suggest that enhanced thrombogenicity could be the main mechanism to explain the elevated FFA levels in patients with cardioembolic stroke.

Impact of serum albumin levels on long-term outcomes in patients undergoing percutaneous coronary intervention

Epidemiological studies have demonstrated an association between low serum albumin levels and both coronary artery disease (CAD) and mortality. However, the long-term clinical impact of low serum albumin level in patients with CAD undergoing percutaneous coronary intervention (PCI) has not yet been fully investigated. We studied 2860 all-comer patients with CAD who underwent their first PCI and had data available for pre-procedural serum albumin between 2000 and 2011. Patients were assigned to tertiles based on pre-procedural albumin levels. We evaluated the incidence of major adverse cardiac events (MACE), including all-cause death and nonfatal myocardial infarction. Mean albumin level was 4.0 ± 0.5 g/dL. Lower albumin levels were associated with older age, lower body mass index (BMI), and higher prevalences of female sex, ACS and chronic kidney disease (CKD). During the median follow-up period of 7.4 years, Kaplan-Meier curves showed ongoing divergence in rates of MACE among albumin tertiles (albumin <3.8 g/dl: 44.3% vs. 3.8-4.1 g/dl: 38.0% vs. >4.1 g/dl: 22.9%; log-rank p < 0.0001). After adjusting for established cardiovascular risk factors including age, acute coronary syndrome, BMI and CKD, serum albumin levels were significantly associated with incidence of MACE (HR 1.74 per 1-g/dl decrease, 95% CI 1.34-2.26, p < 0.0001) and all-cause mortality (HR 1.74, 95% CI 1.30-2.33, p = 0.0002). Pre-PCI low serum albumin level was associated with worse long-term outcomes, independent of traditional risk factors. Assessing albumin levels may allow risk stratification in patients with CAD undergoing PCI.

Effects of equivalent sympathetic activation during hypoglycemia on endothelial function and pro-atherothrombotic balance in healthy individuals and obese standard treated type 2 diabetes

OBJECTIVE

Recent studies in type 2 diabetes have reported an association between hypoglycemia and severe cardiovascular adverse events, which are relatively increased in standard versus intensively treated individuals. The aim of this study was to determine the effects of equivalent sympathetic nervous system (SNS) activity during moderate hypoglycemia on in-vivo endothelial function, pro-inflammatory, pro-atherothrombotic, and pro-coagulant responses in healthy and standard treated type 2 diabetes individuals.

RESEARCH DESIGN AND METHODS

Eleven type 2 diabetes and 16 healthy individuals participated in single 2day studies. Day 1 involved a 2h hyperinsulinemic/euglycemic clamp and day 2, a 2h hyperinsulinemic/hypoglycemic clamp of 3.2±1mmol/L in type 2 diabetes and (2.9±0.1mmol/L) in healthy individuals.

RESULTS

ICAM-1, VCAM-1, P-selectin, PAI-1, VEGF and endothelin-1 (ET-1) fell during hyperinsulinemic euglycemia but increased during hypoglycemia in type 2 diabetes and healthy individuals. Epinephrine and norepinephrine levels were equivalent during hypoglycemia in type 2 DM and healthy individuals. However, despite similar SNS drive but milder and hypoglycemia there were greater ICAM-1, VCAM-1, PAI-1, VEGF and ET-1 responses in the type 2 diabetes group. Endogenous and exogenous nitric oxide mediated arterial vasodilation were also impaired only during hypoglycemia in type 2 diabetes.

CONCLUSION

We conclude that, milder hypoglycemia but equivalent SNS activation results in more diffuse endothelial dysfunction and a greater pro-inflammatory, pro-atherothrombotic and pro-coagulant state in standard treated type 2 diabetes as compared to healthy individuals.