Fibrin D-dimer and coronary heart disease: prospective study and meta-analysis

Inflammation in HIV and Its Impact on Atherosclerotic Cardiovascular Disease

People living with HIV have a 1.5- to 2-fold increased risk of developing cardiovascular disease. Despite treatment with highly effective antiretroviral therapy, people living with HIV have chronic inflammation that makes them susceptible to multiple comorbidities. Several factors, including the HIV reservoir, coinfections, clonal hematopoiesis of indeterminate potential (CHIP), microbial translocation, and antiretroviral therapy, may contribute to the chronic state of inflammation. Within the innate immune system, macrophages harbor latent HIV and are among the prominent immune cells present in atheroma during the progression of atherosclerosis. They secrete inflammatory cytokines such as IL (interleukin)-6 and tumor necrosis-α that stimulate the expression of adhesion molecules on the endothelium. This leads to the recruitment of other immune cells, including cluster of differentiation (CD)8+ and CD4+ T cells, also present in early and late atheroma. As such, cells of the innate and adaptive immune systems contribute to both systemic inflammation and vascular inflammation. On a molecular level, HIV-1 primes the NLRP3 (NLR family pyrin domain containing 3) inflammasome, leading to an increased expression of IL-1β, which is important for cardiovascular outcomes. Moreover, activation of TLRs (toll-like receptors) by HIV, gut microbes, and substance abuse further activates the NLRP3 inflammasome pathway. Finally, HIV proteins such as Nef (negative regulatory factor) can inhibit cholesterol efflux in monocytes and macrophages through direct action on the cholesterol transporter ABCA1 (ATP-binding cassette transporter A1), which promotes the formation of foam cells and the progression of atherosclerotic plaque. Here, we summarize the stages of atherosclerosis in the context of HIV, highlighting the effects of HIV, coinfections, and antiretroviral therapy on cells of the innate and adaptive immune system and describe current and future interventions to reduce residual inflammation and improve cardiovascular outcomes among people living with HIV.

Taking appreciation to heart: appreciation at work and cardiovascular risk in male employees

Introduction

While perceived appreciation at work has been associated with self-reported health and wellbeing, studies considering biological health markers are lacking. In this study, we investigated whether appreciation at work would relate to coronary heart disease (CHD) risk as well as the specificity of this proposed association.

Methods

Our study comprised a total of 103 male participants, including apparently healthy, medication-free, non-smoking men in the normotensive to hypertensive range (n = 70) as well as medicated hypertensive and CHD patients (n = 33). CHD risk was assessed by blood pressure [mean arterial pressure (MAP)], the diabetes marker glycated hemoglobin A1c (HbA1c), blood lipids [total cholesterol (TC)/high-density lipoprotein-cholesterol (HDL-C) ratio], coagulation activity (D-dimer and fibrinogen), and inflammation [interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP)]. Perceived appreciation at work, as well as potentially confounding psychological factors (social support, self-esteem, and work strain due to a lack of appreciation), were measured by self-report questionnaires.

Results

We found higher appreciation at work to relate to lower overall composite CHD risk (p's ≤ 0.011) and, in particular, to lower MAP (p's ≤ 0.007) and lower blood lipids (p's ≤ 0.031) in medication-free participants as well as all participants. This overall association was independent of confounding factors, including related psychological factors (p's ≤ 0.049).

Discussion

Our findings indicate that appreciation at work might be an independent health-promoting resource in terms of CHD risk. Implications include that encouraging appreciation at work may help reduce the development and progression of CHD.

A Systematic Review of Intervention Trials Utilizing Biomarkers Among Informal Caregivers of People with Alzheimer's Disease & Related Dementias

Informal caregivers of people with Alzheimer's Disease and Related Dementias (ADRD) experience unique stressors, reduced quality of life, and report poorer health, compared to non-caregivers. Throughout the last thirty years, researchers have developed and tested various psychosocial interventions and their ability to improve caregiver health. Due to an exclusive focus on self-report methods, however, no existing systematic literature reviews specifically examine intervention studies employing biomarkers; this systematic review aims to address this gap in the literature. In each database (PubMed and Web of Science, respectively), a title search was conducted with the following keywords: "alzheimer*" OR "dementia" AND "caregiv*" AND "intervention", followed by a second search using identical keywords except "intervention" was replaced with "program." Study or intervention protocol articles, exclusively qualitative studies, cultural applicability papers, dissemination studies, descriptive articles or program reports, acceptability/feasibility studies, studies utilizing formal caregiving samples, commentaries, review papers, and meta-analyses, erratums/corrections, measure development articles, factor analyses, and case reports were excluded from the final pool of studies. In this systematic review, the findings of 14 studies are summarized, and are organized based on specific types of biomarkers: neuroendocrine, immune, and autonomic physiological. Overall, the review yielded mixed results, which may, in part, be due to differences in the types of interventions tested, as well as differing biomarker measurement, methodology, and analysis. More biobehavioral intervention trials are needed among ADRD caregivers. Including biological parameters as pre- and post-measures can shed insight into the extent to which interventions may help caregivers heal from the stress of caregiving.

The use of D-dimer in the diagnosis and risk assessment of intracardiac thrombus among patients with dilated cardiomyopathy

D-dimer is a biomarker of coagulation and fibrinolytic system activation in response to the body's hypercoagulable state. The study aims to investigate the usefulness of D-dimer in diagnosing and assessing the risk of intracardiac thrombus in patients with dilated cardiomyopathy (DCM). Consecutively enrolled in this study were patients with DCM who were admitted to our center for the first time. The diagnostic value was evaluated using the receiver operating characteristic (ROC) curve. Additionally, we used univariate and multivariate logistic regression to investigate the association between D-dimer and intracardiac thrombus. We also performed smooth curve fitting, threshold saturation effect analysis, and subgroup analysis. In total, 534 patients were enrolled in the study, and among them, 65 patients had intracardiac thrombus. Mural thrombus was the predominant type of thrombus, which was mainly located in the left ventricular apex. The optimal cut-off value of D-dimer for the diagnosis of intracardiac thrombus was 484 ng/mL, with a sensitivity and specificity of 0.769 and 0.646, respectively. In both unadjusted and adjusted logistic regression models, a positive association was found between D-dimer and intracardiac thrombus. Curve fitting and threshold effect analysis revealed two inflection points in the relationship between D-dimer and intracardiac thrombus (non-linear test: P = 0.032). When D-dimer was equal to 362 ng/mL, the odds ratio (OR) was 1, and the risk of thrombus gradually increased until it reached 4096 ng/mL, after which the trend no longer increased. Within this range, a twofold increase in D-dimer was associated with a 103.2% increased risk (OR = 2.032; 95% CI 1.293-3.193; P < 0.01). In the subgroup analysis, there was a significant interaction between D-dimer and BMI on intracardiac thrombus (P value for interaction was 0.013), and the risk was higher in patients with a BMI ≥ 25 kg/m2 (OR = 3.44; 95% CI 1.86-6.36; P < 0.01).

Clinical significance of D-dimer levels during acute period in ischemic stroke

BACKGROUND

Initial D-dimer level is a well-known prognostic parameter in patients with acute ischemic stroke (AIS). However, there have been no studies on the clinical significance of follow-up D-dimer levels. In this study, we evaluated the association between initial and follow-up D-dimer levels and early neurological deterioration (END) in patients with AIS.

METHODS

We included consecutive patients with AIS who had a positive initial D-dimer test (> 0.55 mg/L) between March 2021 and November 2022. The follow-up D-dimer test was performed on the 7th day after hospitalization and on the day of discharge if discharged earlier. END was defined as an increase of ≥ 2 in the total NIHSS score, or ≥ 1 in the motor NIHSS score within the first 7 days of admission. As medical conditions closely associated with the initial and follow-up D-dimer levels in AIS patients, we also evaluated the history of cancer, active cancer, and venous thromboembolism (VTE) that occurred during hospitalization together.

RESULTS

A total of 246 patients with AIS were evaluated (median age: 87 years, male: 56.5%). In multivariable logistic regression analysis, the initial D-dimer level was closely associated with END after adjusting for confounders (adjusted odds ratio [aOR]: 1.48, 95% CI: 1.06-2.05). The follow-up D-dimer level also showed a close correlation with END (aOR: 1.60, 95% CI: 1.16-2.20). Regarding the analysis of the association between D-dimer levels and underlying cancer or VTE, the initial D-dimer level showed a statistically significant positive relationship only with active cancer (P = 0.024). On the other hand, the follow-up D-dimer level was found to be statistically significantly associated with a history of cancer (P = 0.024), active cancer (P = 0.001), and VTE (P = 0.001).

CONCLUSIONS

Initial and follow-up D-dimer levels were associated with END in AIS patients. Particularly, the follow-up D-dimer level showed a clear correlation not only with END but also with the underlying cancer or the occurrence of VTE during the acute period.

Association of hemostasis and inflammation biomarkers with outcomes in acute coronary syndromes

Plaque rupture triggers a prothrombotic response that is counterbalanced by a fibrinolytic response. d -dimer serves as a marker of both processes. Inflammatory mediators are also released, evidenced with the rise of high-sensitive C reactive protein (hsCRP). Current evidence with these biomarkers has shown conflicting results. Determine an association between d -dimer and hsCRP within hospital and 1-year mortality in patients with acute coronary syndromes. In total, 127 patients were included. In-hospital mortality was 5.7%, and 1-year all-cause and cardiovascular mortality were 14.6 and 9.7%, respectively. The median of admission d -dimer for patients who died during hospital stay was higher than those who survived [4.59 (interquartile ranges (IQR) 1.94-6.05 μg/ml fibrinogen equivalent units (FEU)) vs. 0.56 (IQR 0.31-1.12 μg/ml FEU), P  = 0.001]. At 1-year follow-up, the median of admission d -dimer for patients who died was significantly higher than those who survived: 1.55 (IQR 0.91-5.08 μg/ml FEU) vs. 0.53 (IQR 0.29-0.90 μg/ml FEU), P  < 0.001. Positive d -dimer vs. negative d -dimer at admission analysis evidenced that almost 25% of the positive patients were dead at 1-year follow-up (22.4 vs. 2.4% negative d -dimer, P  = 0.011). Multivariate logistic regression analysis showed that d -dimer has an independent association with 1-year mortality [odds ratio 1.06 (95% confidence interval 1.02-1.10), P  = 0.006]. Positive significative correlations between d -dimer and hsCRP levels ( R  = 0.56, P  < 0.001) were found. High levels of admission d -dimer were strongly associated with in-hospital and 1-year mortality. Significant correlations with hsCRP could explain the inflammatory nature that led to poorer outcomes. d -dimer could be useful in risk stratification in acute coronary syndromes; however, a specific threshold should be defined for this type of patient.

Extent of mural thrombus is not associated with increased 5-year mortality following elective AAA repair

BACKGROUND

Mural thrombus in abdominal aortic aneurysm (AAA) has been associated with increased rates of aneurysm growth as well as adverse cardiovascular events. The extent of mural thrombus in thoracoabdominal aortic aneurysms has recently been linked to 1-year mortality following endovascular repair and has been hypothesized as a marker for reduced cardiac reserve. This study investigates whether the extent of mural thrombus in infra-renal AAA is associated with 5-year mortality following elective repair.

METHODS

Retrospective review of all patients undergoing elective infra-renal AAA repair at a single academic medical center between 2007 and 2016 was performed. The following variables at the time of surgery were investigated for association with 5-year mortality: age, sex, ethnicity, insurance status and co-morbidities, repair type, renal insufficiency, end-stage renal disease on dialysis, history of smoking, coronary artery disease, congestive heart failure, diabetes mellitus, hypertension, stroke, chronic obstructive pulmonary disease, body mass index category, AAA diameter, and ratio of aortic thrombus to total aneurysm diameter.

RESULTS

Amongst 427 patients undergoing infra-renal AAA repair during the study period, 232 met extensive inclusion criteria. Univariate analysis found mean age (76 vs 72, p < 0.01), age cohort over 72 years (OR = 1.9, p = 0.04), renal insufficiency (OR = 3.1, p < 0.01), ESRD (OR = 6.5, p < 0.01), AAA diameter 6 cm or greater (OR = 2.3, p < 0.01), and mean AAA diameter (61.36 vs 56.99 mm, p < 0.01) all predictive of 5-year mortality. Multivariate analysis revealed renal insufficiency (p < 0.01) and AAA diameter 6 cm or greater (p = 0.03) to be significantly associated with 5-year mortality. The extent of mural thrombus was identical between 5-year survivors and non-survivors. The mean inner to outer AAA diameter was 0.65 in the survivor cohort and 0.64 in the mortality cohort. Inner to outer ratio of < 0.5 was identified in 23% of 5-year survivors and 27% of the mortality group.

CONCLUSIONS

In our experience, the extent of mural thrombus in AAA does not influence long-term survival after elective repair. AAA repair may provide protection against circulating components of mural thrombus which have the potential to promote atherosclerotic-related adverse events. Patients with renal insufficiency and larger AAA have increased risk of mortality 5 years after elective repair.

Influence of ejection fraction on biomarker expression and response to spironolactone in people at risk of heart failure: findings from the HOMAGE trial

BACKGROUND

Left ventricular ejection fraction (LVEF) can provide hemodynamic information and may influence the response to spironolactone and other heart failure (HF) therapies.

AIMS

To study the patient characteristics and circulating protein associations with LVEF, and whether LVEF influenced the response to spironolactone.

METHODS

HOMAGE enrolled patients aged >60 years at high risk of developing HF with a LVEF ≥45%. 527 patients were randomized to either spironolactone or standard-of-care for ≈9 months. 276 circulating proteins were measured using Olink® technology.

RESULTS

364 patients had available LVEF determined by the Simpson's bi-plane method. The respective LVEF tertiles were: Tertile1:<60% (N = 122), Tertile2:60%-65% (N = 121), and Tertile3:>65% (N = 121). Patients with a LVEF>65% had smaller LV chamber size and volumes, and lower natriuretic peptide levels. Compared to patients with a LVEF<60%, those with LVEF>65% had higher levels of circulating c-c motif chemokine ligand-23 and interleukin-8, and lower levels of tissue plasminogen activator, BNP, S100 calcium binding protein A12, and collagen type I alpha 1 chain (COL1A1). Spironolactone significantly reduced the circulating levels of BNP and COL1A1 without significant treatment-by-LVEF heterogeneity: BNP change β = -0.36 Log₂ and COL1A1 change β = -0.16 Log₂ (P < 0.0001 for both; interactionP>0.1 for both). Spironolactone increased LVEF from baseline to month 9 by 1.1%, P = 0.007.

CONCLUSION

Patients with higher LVEF had higher circulating levels of chemokines and inflammatory markers and lower levels of stretch, injury, and fibrosis markers. Spironolactone reduced the circulating levels of natriuretic peptides and type 1 collagen, and increased LVEF. This article is protected by copyright. All rights reserved.

Exploring the association of fibrinogen and CRP with the clinical spectrum of CAD and periprocedural outcomes in patients undergoing percutaneous coronary interventions

BACKGROUND

The pathophysiology of an atherosclerotic plaque is mediated by the mechanisms involving thrombus formation and systemic inflammation. While C-reactive protein (CRP) levels are useful in predicting a cardiovascular event in intermediate risk population, the usefulness of routinely measuring fibrinogen in patients with acute coronary syndrome (ACS) is debatable. Also, data on the association of these markers with periprocedural outcomes in patients undergoing percutaneous coronary interventions (PCI) is scarce.

AIMS

The study aimed to determine whether the levels of fibrinogen and CRP vary across the different spectra of CAD and whether they have any correlation with cardiac Troponin I levels.

MATERIALS AND METHODS

A total of 284 patients with coronary artery disease undergoing percutaneous coronary intervention were included in the study. Complete blood count, serum lipid profile, serum CRP, fibrinogen, and troponin I were measured for all patients.

RESULTS

Patients with STEMI had significantly higher levels of CRP as compared to those with unstable angina (USA) and chronic stable angina (CSA). Patients presenting with ACS had significantly higher baseline fibrinogen as compared to those with CSA. A significant positive correlation between CRP and admission Troponin I (r = 0.50; P < 0.05) as well as fibrinogen and admission troponin I (r = 0.30; P < 0.05) was observed. The CRP levels were significantly higher in 15 patients with periprocedural MI as compared to those who did not develop periprocedural MI.

CONCLUSIONS

: The levels of the markers of inflammation and atherothrombosis vary with presentation across varied spectra of CAD with generally higher levels in acute presentation and in those who develop periprocedural MI.

Genome-wide association study of high-sensitivity C-reactive protein, D-dimer, and interleukin-6 levels in multiethnic HIV+ cohorts

OBJECTIVES

Elevated levels of interleukin-6 (IL-6), D-dimer, and C-reactive protein (hsCRP) are associated with increased incidence of comorbid disease and mortality among people living with HIV (PLWH). Prior studies suggest a genetic basis for these biomarker elevations in the general population. The study objectives are to identify the genetic basis for these biomarkers among PLWH.

METHODS

Baseline levels of hsCRP, D-dimer, and IL-6, and single nucleotide polymorphisms (SNPs) were determined for 7768 participants in three HIV treatment trials. Single variant analysis was performed for each biomarker on samples from each of three ethnic groups [African (AFR), Admixed American (AMR), European (EUR)] within each trial including covariates relevant to biomarker levels. For each ethnic group, the results were pooled across trials, then further pooled across ethnicities.

RESULTS

The transethnic analysis identified three, two, and one known loci associated with hsCRP, D-dimer, and IL-6 levels, respectively, and two novel loci, FGB and GCNT1, associated with D-dimer levels. Lead SNPs exhibited similar effects across ethnicities. Additionally, three novel, ethnic-specific loci were identified: CATSPERG associated with D-dimer in AFR and PROX1-AS1 and TRAPPC9 associated with IL-6 in AFR and AMR, respectively.

CONCLUSION

Eleven loci associated with three biomarker levels were identified in PLWH from the three studies including six loci known in the general population and five novel loci associated with D-dimer and IL-6 levels. These findings support the hypothesis that host genetics may partially contribute to chronic inflammation in PLWH and help to identify potential targets for intervention of serious non-AIDS complications.

Plasma tissue factor and immune activation are associated with carotid intima-media thickness progression in treated HIV infection

OBJECTIVES

We evaluated the roles of biomarkers of immune activation with carotid intima-media thickness (CIMT) progression in treated HIV infection.

DESIGN

Longitudinal observational study of 118 treated and virologically suppressed individuals.

METHODS

We measured biomarkers of immune activation at baseline using cryopreserved samples. CIMT was measured at baseline and longitudinally using high-resolution ultrasound. Linear regression was used to estimate biomarker associations with CIMT progression, and logistic regression was used to model plaque progression.

RESULTS

The median duration of follow-up was 2.0 years. The median annual rate of change in mean CIMT was 6.0%. Rates of progression were more rapid in the bifurcation (5.6%/year, P = 0.006) and internal (6.5%/year, P = 0.0008) than common CIMT (4.3%/year). Incident plaque occurred in 13 of the 52 individuals without baseline plaque. In multivariable adjusted analysis, plasma tissue factor and monocyte chemoattractant protein-1 were associated with more rapid common CIMT progression (0.058 mm/year, P = 0.0004 and 0.067 mm/year, P = 0.017; all estimates per doubling). CD8 T-cell count and percentage of HLA-DRCD38CD8 T cells were associated with more rapid internal CIMT progression (0.10 mm/year, P = 0.008 and 0.054 mm/year, P = 0.045). CD8 T-cell count was also associated with 0.068 mm/year more rapid mean CIMT progression (P = 0.011). Each 10% increase in CD4 T-cell count at baseline was associated with a 34% reduced odds of plaque progression (P = 0.018).

CONCLUSION

Residual immune activation and plasma tissue factor are independently associated with CIMT progression in treated HIV infection. Interventions targeting coagulation and inflammatory pathways to reduce cardiovascular disease risk in HIV merit additional investigations.

Factors associated with the risk of cardiovascular disease in family caregivers of people with dementia: a systematic review

Objective

This study aimed to systematically review studies that reported factors associated with the risk of cardiovascular disease (CVD) in family caregivers of people with dementia (PWD).

Methods

Literature was searched in PubMed, Medline, CINAHL, and PsycINFO using keywords generated from the terms “dementia”, “caregiver”, and “cardiovascular disease”. We included studies that examined factors associated with CVD risk in family caregivers of PWD, those with longitudinal or cross-sectional study designs, and those published in English.

Results

A total of 34 studies were included in this review. Stress and depressive symptoms, pleasant leisure activity, coping self-efficacy and coping strategy, physical activity, and social support were the main modifiable associated factors of CVD risk in family caregivers of PWD. However, the association between sleep and CVD risk was unclear. Caregiving status, the duration of caregiving, genes, and race, were the main non-modifiable associated factors of CVD risk in family caregivers.

Conclusion

This review showed seven modifiable factors of CVD risk. In particular, leisure activities, physical activity, and social support were significantly negatively associated with the risk of CVD. Researchers and clinical professionals are recommended to consider these risk factors when they develop interventions to reduce CVD risk in family caregivers of PWD.

Association of complete blood count parameters, d-dimer, and soluble P-selectin with risk of arterial thromboembolism in patients with cancer

BACKGROUND

Patients with cancer are at risk of developing arterial thromboembolism (ATE). With the prevalence of cancer and cardiovascular diseases on the rise, the identification of risk factors for ATE in patients with cancer is of emerging importance.

OBJECTIVES

As data on the association of potential biomarkers with risk of ATE in patients with cancer are scarce, we conducted a cohort study with the aim to identify blood-based biomarkers for ATE risk prediction in patients with cancer.

PATIENTS/METHODS

Overall, 1883 patients with newly diagnosed cancer or progressive disease after complete or partial remission were included and followed for 2 years. Venous blood was drawn at study inclusion for measurement of complete blood count parameters, total cholesterol, d-dimer, and soluble P-selectin (sP-selectin) levels.

RESULTS

The 2-year cumulative incidence of ATE was 2.5%. In univariable analysis, red cell distribution width (subdistribution hazard ratio (SHR) per doubling: 4.4, 95% CI: 1.4-14.1), leukocyte count (1.2, 1.1-1.5), neutrophil count (1.6, 1.1-2.3), and sP-selectin levels (1.9, 1.3-2.7) were associated with risk of ATE in patients with cancer; d-dimer was not associated with the risk of ATE (1.1, 0.9-1.4). After adjustment for age, sex, and smoking status the association prevailed for the neutrophil count (adjusted [adj.] SHR per doubling: 1.6, 1.1-2.4), and sP-selectin levels (1.8, 1.2-2.8).

CONCLUSIONS

An elevated absolute neutrophil count and higher sP-selectin levels were associated with an increased risk of ATE in patients with cancer. Their role for predicting cancer-related ATE needs to be validated in further studies.

The Assessment of Left Ventricle Function and Subclinical Atherosclerosis in Patients with Acute Myeloid Leukemia

Aim To assess the onset of early left ventricular (LV) systolic and diastolic function impairment and the subclinical atherosclerosis following chemotherapy in patients diagnosed with acute myeloid leukemia (AML).

MATERIALS AND METHODS

Thirty patients diagnosed with AML with no cardiac history, having LV ejection fraction (LVEF) >50%, were evaluated at baseline and 6 months after starting four cycles of chemotherapy. We measured LV function, global longitudinal strain and subclinical atherosclerosis markers: intima-media thickness (IMT), arterial stiffness aortic pulse wave velocity (PWVAo) and ankle-brachial index (ABI).

RESULTS

LVEF had decreased at 6 months after treatment initialization (p<0.001), the same changes being observed for LV fraction shortening (p<0.001), mitral annular plane systolic excursion and S' wave (p<0.001 and p<0.05). Bilateral IMT and PWVAo significantly increased, 12 out of 30 patients (40%) had LVEF ≤50% after 6 months of chemotherapy, five of them receiving daunorubicin at more than 500 mg/m²/injection.

CONCLUSION

LV function is impaired after 6 months of chemotherapy, with early changes of subclinical atherosclerosis becoming evident.

An exploratory factor analysis of inflammatory and coagulation markers associated with femoral artery atherosclerosis in the San Diego Population Study

BACKGROUND AND AIMS

Several biomarkers of inflammation and coagulation have been implicated in lower extremity atherosclerosis. We utilized an exploratory factor analysis (EFA) to identify distinct factors derived from circulating inflammatory and coagulation biomarkers then examined the associations of these factors with measures of lower extremity subclinical atherosclerosis, including the ankle-brachial index (ABI), common and superficial femoral intima-media thickness (IMT), and atherosclerotic plaque presence, burden, and characteristics.

METHODS

The San Diego Population Study (SDPS) is a prospective, community-living, multi-ethnic cohort of 1103 men and women averaged age 70. Regression analysis was used to assess cross-sectional associations between the identified groupings of biomarkers (factors) and the ABI and femoral artery atherosclerosis measurements.

RESULTS

Two biomarker factors emerged from the factor analysis. Factor 1 consisting of C-reactive protein (CRP), interleukin (IL)-6, and fibrinogen was significantly associated with higher odds (OR = 1.99, p < 0.01) of a borderline ABI value (0.91-0.99), while Factor 2 containing D-dimer and pentraxin (PTX)-3 was significantly associated with higher common femoral artery (CFA) IMT (β = 0.23, p < 0.01) and lower ABI (β = -0.03, p < 0.01).

CONCLUSIONS

Two groupings of biomarkers were identified via EFA of seven circulating biomarkers of inflammation and coagulation. These distinct groups are differentially associated with markers of lower extremity subclinical atherosclerosis. Our findings suggest that high inflammatory and coagulation burden were better markers of more severe lower-extremity disease as indicated by low ABI rather than early atherosclerotic lesion development in the femoral artery.

Diagnostic Value of D-Dimer in Acute Myocardial Infarction Among Patients With Suspected Acute Coronary Syndrome

Background

The role of D-dimer as a diagnostic marker in myocardial infarction (MI) and acute coronary syndrome (ACS) is still a question. The aim of this study was to evaluate the diagnostic value of D-dimer in the diagnosis of AMI in patients suspected with ACS.

Methods

This cross-sectional study was conducted on patients suspected with ACS. Serial standard 12-lead electrocardiogram (ECG), D-dimer, and troponin tests were done for all the patients. According to the examinations, ECG changes, and troponin, patients were allocated into two groups of MI and unstable angina (UA). Chi-square, independent t-test, and Pearson correlation test were used by SPSS ver, 17. Cut-off point of D-dimer for MI diagnosis was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

Seventy-five patients with a mean age of 63.1 ± 9.75 years were studied in two groups of MI (n = 34) and UA (n = 41). Patients were homogeneous based on age, gender, and risk factors for diabetes and dyslipidemia. D-dimer in patients with MI patients was higher than in patients with UA (P = 0.001). The optimal cut-off point of D-dimer for diagnosis of MI was 548 mEq/L with sensitivity and specifity of 63.4% and 91.2%, respectively.

Conclusions

Based on the results of this study, it seems that the measurement of D-dimer serum level can be appropriate as a marker with high sensitivity and relatively high specificity for differentiating MI from UA in patients with suspected ACS.

Elevated level of D-dimer increases the risk of stroke

The aim of this study was to systematically evaluate the association between D-dimer level and the risk of stroke through performing a meta-analysis. PubMed, Web of Science, EMBASE and Cochrane Library were searched for potentially eligible literature. Prospective observational studies or case-control studies were included. The study characteristics and relevant data were extracted. Hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to estimate the association between D-dimer level and the risk of stroke. Seven prospective studies with 22,207 patients and three case-control studies with 2,248 patients were included. For the prospective studies, the pooled HRs of higher D-dimer level for all types of stroke, ischemic stroke and hemorrhagic stroke were 1.55 (95% CI, 1.28- 1.87), 1.62 (95% CI, 1.18-2.22) and 1.30 (95% CI, 0.63-2.68), respectively. The pooled HRs per SD increase in log D-dimer for all types of stroke, ischemic stroke and hemorrhagic stroke were 1.16 (95% CI, 1.06-1.26), 1.11 (95% CI, 1.03-1.21) and 1.11 (95% CI, 0.95-1.30), respectively. For the case-control studies, the pooled OR of higher D-dimer level for acute ischemic stroke was 2.06 (95% CI, 1.08-3.96). No significant publication bias was found in the meta-analysis. In conclusion, our results suggested that higher D-dimer level was associated with higher risk of stroke, especially ischemic stroke.

Association between statin use and plasma D-dimer levels

D-dimers, specific breakdown fragments of cross-linked fibrin, are generally used as circulating markers of activated coagulation. Statins influence haemostatic factors, but their effect on plasma D-dimer levels is controversial. Therefore, the aim of this meta-analysis was to evaluate the association between statin therapy and plasma D-dimer levels. We searched PubMed, Web of Science, Cochrane Library, Scopus and EMBASE (up to September 25, 2014) to identify randomised controlled trials (RCTs) investigating the impact of statin therapy on plasma D-dimer levels. Two independent reviewers extracted data on study characteristics, methods and outcomes. Meta-analysis of data from nine RCTs with 1,165 participants showed a significant effect of statin therapy in reducing plasma D-dimer levels (standardised mean difference [SMD]: –0.988 µg/ml, 95 % confidence interval [CI]: –1.590 – –0.385, p=0.001). The effect size was robust in sensitivity analysis and omission of no single study significantly changed the overall estimated effect size. In the subgroup analysis, the effect of statins on plasma D-dimer levels was significant only in the subsets of studies with treatment duration ≥ 12 weeks (SMD: –0.761 µg/ml, 95 %CI: –1.163– –0.360; p< 0.001), and for lipophilic statins (atorvastatin and simvastatin) (SMD: –1.364 µg/ml, 95 % CI: –2.202– –0.526; p=0.001). Hydrophilic statins (pravastatin and rosuvastatin) did not significantly reduce plasma D-dimer levels (SMD: –0.237 µg/ml, 95 %CI: –1.140–0.665, p=0.606). This meta-analysis of RCTs suggests a decrease of plasma D-dimer levels after three months of statin therapy, and especially after treatment with lipophilic statins. Well-designed trials are required to validate these results.

Note: The review process for this paper was fully handled by Christian Weber, Editor in Chief.

High-molecular-weight kininogen and the intrinsic coagulation pathway in patients with de novo acute myocardial infarction

After an acute ischaemic event serum proteins may change reflecting the ischaemic damage. Proteomic studies could provide new insights into potential biomarkers in the evolution of ischaemic syndromes. In this study we have investigated the coordinated changes in coagulation-related proteins in the evolution after an acute myocardial infarction (AMI). Serum proteome (2D-electrophoresis and MALDI-TOF/ TOF) of AMI-patients within the first 6 hours after event onset (admission-time) and 3 days after were compared to controls. Systems biology and bioinformatic analysis were performed to identify the differentially expressed canonical pathways. In silico analysis of differential proteins revealed changes in the intrinsic coagulation pathway in the early phase post-AMI. The two identified high-molecular weight kininogen (HMWK) clusters were inversely correlated in AMI patients at admission, being the intensity of the low-molecular-weight form inversely related to myocardial necrosis (p<0.05). Factor XI (FXI) levels were decreased in AMI patients at admission and normalised 3 days after (p<0.05). There was an early increase in fibrinogen gamma and D-dimer at admission, followed by a decrease in fibrinogen turnover 3 days after (p<0.05). The influence of elapsed time of ischaemia on fibrinogen distribution changes was validated in coronary thrombi retrieved by thromboaspiration. In conclusion, our results demonstrate an active exchange between HMWK forms and a decrease in FXI indicative of intrinsic pathway activation, together with an increase in fibrinogen gamma turnover and D-dimer formation in the early phase post-AMI. Moreover, coronary thrombi showed a dynamic evolution in fibrinogen composition depending on the duration of ischaemia influencing serum fibrinogen-related products content.

Elevated levels of D-dimers increase the risk of ischaemic and haemorrhagic stroke

Elevated D-dimer levels are reportedly associated with coronary artery disease. It was the study objective to investigate the association of baseline D-dimer levels with strokes that occurred in the European Prospective Investigation into Cancer and Nutrition-Italy cohort. Using a nested case-cohort design, a centre-–stratified sample of 832 subjects (66 % women, age 35–71) was selected as subcohort and compared with 289 strokes in a mean follow-up of nine years. D-dimers were measured by an automated latex-enhanced immunoassay (HemosIL-IL). The multivariable hazard ratios were estimated by a Cox regression model using Prentice method. Individuals with elevated D-dimer levels had significantly higher risk of incident stroke. It was evident from the second quartile (D-dimers > 100 ng/ml) and persisted almost unchanged for higher D-dimers (hazard ratio [HR] 2.10, 95 % confidence interval [CI]: 1.28–3.47; 2.42, 95 %CI: 1.44–4.09 and 2.10, 95 %CI: 1.27–3.48 for the second, third or fourth quartile compared with the lowest quartile, respectively). The association was independent of several confounders, including triglycerides and C-reactive protein. No differences were observed in men and women (P for interaction= 0.46), in hypertensive or non-hypertensive subjects (P for interaction= 0.88) or in subjects with low (< 1 mg/l) or elevated (≥ 1 mg/l) C-reactive protein (P for interaction=0.35). After stratification for stroke type, the hazard ratio for every standard deviation increase was statistically significant both for ischaemic (1.21; 95 %CI: 1.01 to 1.45) and haemorrhagic (1.24; 95 %CI: 1.00 to 1.65) strokes. In conclusion, our data provide clear evidence that elevated levels of D-dimers are potential risk factors not only for ischaemic but also for haemorrhagic strokes.

A Test in Context: D-Dimer

D-dimer is a soluble fibrin degradation product that results from ordered breakdown of thrombi by the fibrinolytic system. Numerous studies have shown that D-dimer serves as a valuable marker of activation of coagulation and fibrinolysis. Consequently, D-dimer has been extensively investigated for the diagnosis of venous thromboembolism (VTE) and is used routinely for this indication. In addition, D-dimer has been evaluated for determining the optimal duration of anticoagulation in VTE patients, for diagnosing and monitoring disseminated intravascular coagulation, and as an aid in the identification of medical patients at high risk for VTE. Thus, quantification of D-dimer levels serves an important role in guiding therapy. This review: 1) describes how D-dimer is generated; 2) reviews the assays used for its detection; and 3) discusses the role of D-dimer determination in these various conditions.

D-Dimer in African Americans: Whole Genome Sequence Analysis and Relationship to Cardiovascular Disease Risk in the Jackson Heart Study

OBJECTIVE

Plasma levels of the fibrinogen degradation product D-dimer are higher among African Americans (AAs) compared with those of European ancestry and higher among women compared with men. Among AAs, little is known of the genetic architecture of D-dimer or the relationship of D-dimer to incident cardiovascular disease.

APPROACH AND RESULTS

We measured baseline D-dimer in 4163 AAs aged 21 to 93 years from the prospective JHS (Jackson Heart Study) cohort and assessed association with incident cardiovascular disease events. In participants with whole genome sequencing data (n=2980), we evaluated common and rare genetic variants for association with D-dimer. Each standard deviation higher baseline D-dimer was associated with a 20% to 30% increased hazard for incident coronary heart disease, stroke, and all-cause mortality. Genetic variation near F3 was associated with higher D-dimer (rs2022030, β=0.284, P=3.24×10^-11). The rs2022030 effect size was nearly 3× larger among women (β=0.373, P=9.06×10^-13) than among men (β=0.135, P=0.06; P interaction =0.009). The sex by rs2022030 interaction was replicated in an independent sample of 10 808 multiethnic men and women (P interaction =0.001). Finally, the African ancestral sickle cell variant (HBB rs334) was significantly associated with higher D-dimer in JHS (β=0.507, P=1.41×10^-14), and this association was successfully replicated in 1933 AAs (P=2.3×10^-5).

CONCLUSIONS

These results highlight D-dimer as an important predictor of cardiovascular disease risk in AAs and suggest that sex-specific and African ancestral genetic effects of the F3 and HBB loci contribute to the higher levels of D-dimer among women and AAs.

The Role of Emerging Risk Factors in Cardiovascular Outcomes

PURPOSE OF REVIEW

This review discusses the recent evidence for a selection of blood-based emerging risk factors, with particular reference to their relation with coronary heart disease and stroke.

RECENT FINDINGS

For lipid-related emerging risk factors, recent findings indicate that increasing high-density lipoprotein cholesterol is unlikely to reduce cardiovascular risk, whereas reducing triglyceride-rich lipoproteins and lipoprotein(a) may be beneficial. For inflammatory and hemostatic biomarkers, genetic studies suggest that IL-6 (a pro-inflammatory cytokine) and several coagulation factors are causal for cardiovascular disease, but such studies do not support a causal role for C-reactive protein and fibrinogen. Patients with chronic kidney disease are at high cardiovascular risk with some of this risk not mediated by blood pressure. Randomized evidence (trials or Mendelian) suggests homocysteine and uric acid are unlikely to be key causal mediators of chronic kidney disease-associated risk and sufficiently large trials of interventions which modify mineral bone disease biomarkers are unavailable. Despite not being causally related to cardiovascular disease, there is some evidence that cardiac biomarkers (e.g. troponin) may usefully improve cardiovascular risk scores. Many blood-based factors are strongly associated with cardiovascular risk. Evidence is accumulating, mainly from genetic studies and clinical trials, on which of these associations are causal. Non-causal risk factors may still have value, however, when added to cardiovascular risk scores. Although much of the burden of vascular disease can be explained by 'classic' risk factors (e.g. smoking and blood pressure), studies of blood-based emerging factors have contributed importantly to our understanding of pathophysiological mechanisms of vascular disease, and new targets for potential therapies have been identified.

D-dimer and the Risk of Stroke and Coronary Heart Disease. The REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

D-dimer, a biomarker of coagulation, is higher in blacks than in whites and has been associated with stroke and coronary heart disease (CHD). It was our objective to assess the association of higher D-dimer with stroke and CHD in blacks and whites. REGARDS recruited 30,239 black and white participants across the contiguous US and measured baseline D-dimer in stroke (n=646) and CHD (n=654) cases and a cohort random sample (n=1,104). Cox models adjusting for cardiovascular risk factors determined the hazard ratio (HR) for increasing D-dimer for cardiovascular disease with bootstrapping to assess the difference in HR for CHD versus stroke by race. D-dimer was higher with increasing age, female sex, diabetes, hypertension, pre-baseline cardiovascular disease and higher C-reactive protein (CRP). Accounting for cardiovascular risk factors, each doubling of D-dimer was associated with increased stroke (hazard ratio [HR] 1.15; 95 % confidence interval [CI] 1.01, 1.31) and CHD (HR 1.27; 95 % CI 1.11, 1.45) risk. The difference in the HR between CHD and stroke was 0.20 (95 % CI >0.00, 0.58) for blacks and 0.02 (95 % CI -0.30, 0.27) for whites. CRP mediated 22 % (95 % CI 5 %, 41 %) of the association between D-dimer and CHD and none of the association with stroke. Higher D-dimer increased the risk of stroke and CHD independent of cardiovascular risk factors and CRP, with perhaps a stronger association for CHD versus stroke in blacks than whites. These findings highlight potential different pathophysiology of vascular disease by disease site and race suggesting potential further studies targeting haemostasis in primary prevention of vascular disease.

Serious Non-AIDS Events: Therapeutic Targets of Immune Activation and Chronic Inflammation in HIV Infection

In the antiretroviral therapy (ART) era, serious non-AIDS events (SNAEs) have become the major causes of morbidity and mortality in HIV-infected persons. Early ART initiation has the strongest evidence for reducing SNAEs and mortality. Biomarkers of immune activation, inflammation and coagulopathy do not fully normalize despite virologic suppression and persistent immune activation is an important contributor to SNAEs. A number of strategies aimed to reduce persistent immune activation including ART intensification to reduce residual viremia; treatment of co-infections to reduce chronic antigen stimulation; the use of anti-inflammatory agents, reducing microbial translocation as well as interventions to improve immune recovery through cytokine administration and reducing lymphoid tissue fibrosis, have been investigated. To date, there is little conclusive evidence on which strategies beyond treatment of hepatitis B and C co-infections and reducing cardiovascular risk factors will result in clinical benefits in patients already on ART with viral suppression. The use of statins seems to show early promise and larger clinical trials are underway to confirm their efficacy. At this stage, clinical care of HIV-infected patients should therefore focus on early diagnosis and prompt ART initiation, treatment of active co-infections and the aggressive management of co-morbidities until further data are available.

Extent of regression dilution for established and novel coronary risk factors: results from the British Regional Heart Study

BACKGROUND

Imprecision in measurement of risk factors leads to underestimation of associations with disease outcomes (through regression dilution bias). We examine the extent of this bias for established and novel risk factors for coronary heart disease (CHD) and consider the consequences for CHD prevention.

DESIGN

Prospective cardiovascular study of middle-aged British men followed up over 20 years.

METHODS

Repeated measurements of blood lipids, blood pressure and insulin were available at intervals of 1 week, 4, 16 and 20 years; repeated measurements of homocysteine and haemostatic factors were available over 1 week and 4 years.

RESULTS

The use of single baseline measures of both established and novel risk factors in analysis results in marked underestimation of risk associations, increasing over time. The use of a single baseline measurement of total cholesterol results in a 47% (95% confidence interval 44 to 50%) underestimation of its association with CHD risk during the third decade of follow-up; for diastolic blood pressure the corresponding underestimation is 76% (95% confidence interval 73 to 78%). Ignoring the consequences of regression dilution can also lead to error in the assessment of other risk markers, even those measured precisely.

CONCLUSIONS

The importance of risk factors for CHD can be greatly underestimated by using a single baseline measure in prospective study analyses. Studies that wish to estimate associations between disease risk and usual exposure levels need to take regression dilution effects into account. Failure to do so can lead to serious misinterpretation of the importance of CHD risk factors.

Relevance of Interleukin-6 and D-Dimer for Serious Non-AIDS Morbidity and Death among HIV-Positive Adults on Suppressive Antiretroviral Therapy

Background

Despite effective antiretroviral treatment (ART), HIV-positive individuals are at increased risk of serious non-AIDS conditions (cardiovascular, liver and renal disease, and cancers), perhaps due in part to ongoing inflammation and/or coagulation. To estimate the potential risk reduction in serious non-AIDS conditions or death from any cause that might be achieved with treatments that reduce inflammation and/or coagulation, we examined associations of interleukin-6 (IL-6), D-dimer, and high-sensitivity C-reactive protein (hsCRP) levels with serious non-AIDS conditions or death in 3 large cohorts.

Methods

In HIV-positive adults on suppressive ART, associations of IL-6, D-dimer, and hsCRP levels at study entry with serious non-AIDS conditions or death were studied using Cox regression. Hazard ratios (HR) adjusted for age, gender, study, and regression dilution bias (due to within-person biomarker variability) were used to predict risk reductions in serious non-AIDS conditions or death associated with lower “usual” levels of IL-6 and D-dimer.

Results

Over 4.9 years of mean follow-up, 260 of the 3766 participants experienced serious non-AIDS conditions or death. IL-6, D-dimer and hsCRP were each individually associated with risk of serious non-AIDS conditions or death, HR = 1.45 (95% CI: 1.30 to 1.63), 1.28 (95% CI: 1.14 to 1.44), and 1.17 (95% CI: 1.09 to 1.26) per 2x higher biomarker levels, respectively. In joint models, IL-6 and D-dimer were independently associated with serious non-AIDS conditions or death, with consistent results across the 3 cohorts and across serious non-AIDS event types. The association of IL-6 and D-dimer with serious non-AIDS conditions or death was graded and persisted throughout follow-up. For 25% lower “usual” IL-6 and D-dimer levels, the joint biomarker model estimates a 37% reduction (95% CI: 28 to 46%) in the risk of serious non-AIDS conditions or death if the relationship is causal.

Conclusions

Both IL-6 and D-dimer are independently associated with serious non-AIDS conditions or death among HIV-positive adults with suppressed virus. This suggests that treatments that reduce IL-6 and D-dimer levels might substantially decrease morbidity and mortality in patients on suppressive ART. Clinical trials are needed to test this hypothesis.

Evidence that periodontal treatment improves biomarkers and CVD outcomes

AIM

The aim of this review was to critically appraise the evidence on the impact of periodontal treatment of cardiovascular diseases (CVDs) biomarkers and outcomes.

METHODS

A systematic search was performed in Cinhal, Cochrane, Embase and Medline for relevant articles up to July 2012. Duplicate screening and reference hand searching were performed. Data were then summarized and evidence graded in tables.

RESULTS

The search resulted in: (a) no evidence on the effects of periodontal therapy on subclinical atherosclerosis, serum levels of CD40 ligand, serum amyloid A and monocyte chemoattractant protein-1, (b) limited evidence on the effects of periodontal therapy on arterial blood pressure, leucocyte counts, fibrinogen, tissue necrosis factor-α, sE-selectin, von Willebrand factors, d-dimers, matrix metalloproteinases, oxidative stress and CVD events, and (c) moderate evidence suggesting a negligible effect of periodontal therapy in reducing interleukin-6 and lipids levels, whilst a positive effect in reducing serum C-reactive protein levels and improving endothelial function.

CONCLUSIONS

Periodontal therapy triggers a short-term inflammatory response followed by (a) a progressive and consistent reduction of systemic inflammation and (b) an improvement in endothelial function. There is however limited evidence that these acute and chronic changes will either increase or reduce CVD burden of individuals suffering from periodontitis in the long term.

Evidence that periodontal treatment improves biomarkers and CVD outcomes

AIM

The aim of this review was to critically appraise the evidence on the impact of periodontal treatment of cardiovascular diseases (CVDs) biomarkers and outcomes.

METHODS

A systematic search was performed in Cinhal, Cochrane, Embase and Medline for relevant articles up to July 2012. Duplicate screening and reference hand searching were performed. Data were then summarized and evidence graded in tables.

RESULTS

The search resulted in: (a) no evidence on the effects of periodontal therapy on subclinical atherosclerosis, serum levels of CD40 ligand, serum amyloid A and monocyte chemoattractant protein-1, (b) limited evidence on the effects of periodontal therapy on arterial blood pressure, leucocyte counts, fibrinogen, tissue necrosis factor-a, sE-selectin, von Willebrand factors, d-dimers, matrix metalloproteinases, oxidative stress and CVD events, and (c) moderate evidence suggesting a negligible effect of periodontal therapy in reducing interleukin-6 and lipids levels, whilst a positive effect in reducing serum C-reactive protein levels and improving endothelial function.

CONCLUSIONS

Periodontal therapy triggers a short-term inflammatory response followed by (a) a progressive and consistent reduction of systemic inflammation and (b) an improvement in endothelial function. There is however limited evidence that these acute and chronic changes will either increase or reduce CVD burden of individuals suffering from periodontitis in the long term.

Elevated Levels of Serum Fibrin and Fibrinogen Degradation Products Are Independent Predictors of Larger Coronary Plaques and Greater Plaque Necrotic Core

BACKGROUND

Co-existence of vulnerable plaque and pro-thrombotic state may provoke acute coronary events. It was hypothesized that elevated serum levels of fibrin and fibrinogen degradation products (FDP) are associated with larger total plaque and necrotic core (NC) areas.

METHODS AND RESULTS

Seventy-five patients presenting with stable anginal symptoms (69%) or stabilized acute coronary syndrome (ACS; 31%), and found to have non-obstructive coronary artery disease (CAD) with a fractional flow reserve >0.8, were studied. Invasive virtual histology intravascular ultrasound (VH-IVUS) was performed in 68 LAD arteries, 6 circumflex arteries, and 1 right coronary artery. Serum FDP levels were measured using ELISA technique. Plaque volumetrics and composition were assessed in each VH-IVUS frame and averaged. The median age of patients was 56 (47-63) years; 52% were men and 23% had diabetes. The average length of coronary artery studied was 62 mm. After adjustment for systemic risk factors, medications, CRP levels and ACS, male gender (P<0.001) and serum FDP levels (P=0.02) were independent predictors of a larger NC area. Older age (P<0.001), male gender (P<0.0001) and increased serum FDP level (P=0.03) were associated with a larger plaque area.

CONCLUSIONS

In patients with CAD, a higher serum level of FDP is independently associated with larger plaques and greater plaque NC.

Randomized trial of a multidisciplinary lifestyle intervention in HIV-infected patients with moderate-high cardiovascular risk

OBJECTIVE

To assess the impact of a multidisciplinary lifestyle intervention on cardiovascular risk and carotid intima-media thickness (c-IMT) in HIV-infected patients with Framingham scores (FS) > 10%.

DESIGN

Randomized pilot study; follow-up 36 months.

METHODS

Virologically suppressed adult HIV-1-infected patients with FS >10% were randomized 1:1 to the intervention group (multidisciplinary lifestyle intervention) or control group (routine care). At baseline and months 12, 24 and 36, lipid parameters were analyzed and carotid ultrasound was performed to determine c-IMT and presence of plaques. Biomarkers were measured at baseline and month 36. The primary endpoints were lipid and FS changes at 36 months.

RESULTS

Fifty-four patients were included, 27 in each arm. Median age was 50.5 years, all patients but one were men, and FS was 16.5%. Relative to controls, total and LDL cholesterol had significantly decreased in the intervention group at 24 months (p = 0.039, p = 0.011, respectively). However, no differences between groups were found at month 36 in lipid variables, neither in FS. Tobacco use decreased in the intervention group (p = 0.031). At baseline, 74.5% of patients had subclinical atherosclerosis, and at month 36, we observed a progression in c-IMT that was greater in the intervention group (p = 0.030). D-dimer increased (p = 0.027) and soluble intercellular adhesion molecule-1 decreased (p = 0.018) at 36 months.

CONCLUSIONS

In this cohort of HIV-infected patients with FS>10% and a high percentage of subclinical atherosclerosis, a multidisciplinary lifestyle intervention resulted in a slight improvement in some cardiovascular risk factors and the FS during the first 2 years, but did not prevent c-IMT progression.

Inflammation and hemostasis in atrial fibrillation and coronary heart disease: The REasons for Geographic And Racial Differences in Stroke study

BACKGROUND

Recent studies suggest atrial fibrillation (AF) is an independent risk factor for coronary heart disease (CHD).

AIMS

To determine if alterations in hemostasis or inflammation explain the association between AF and CHD.

METHODS

C-reactive protein (CRP), D-dimer, factor VIII, and fibrinogen were measured in incident CHD cases (n = 647) and a stratified cohort random sample (CRS, n = 1104) between 2003 and 2007 from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Using a case-cohort approach, Cox models examined whether inflammation or hemostasis biomarkers explained the association between AF and CHD.

RESULTS

In participants free of CHD at baseline, 12.2% of CHD cases and 7.1% of the CRS had AF. Over a median follow-up of 4.4 years, all biomarkers were associated with an increased risk of CHD in those with and those without AF after adjusting for CHD risk factors. The association of D-dimer with CHD was greater in those with AF (HR 2.52, 95% CI = 1.49, 4.26) than those without AF (HR 1.34, 95% CI = 1.12, 1.61) (p-interaction = 0.02). Similar interactions were not observed for the other biomarkers.

CONCLUSIONS

Our results suggest that alterations in D-dimer, a marker of hemostasis, explain the association between AF and CHD. Potentially, D-dimer is a useful biomarker to assess CHD risk in persons with AF.

The current role and future prospects of D-dimer biomarker

D-dimers have been discovered as by-products of fibrinolysis. In situations where the fundamental pathology is associated with increased thrombolytic activity, D-dimer assays could serve an integral role in the clinical workup, and have an already established role in the diagnosis of clinical disorders of venous thromboembolism, and disseminated intravascular coagulation. However, there is growing literature suggesting that this is not the only clinical scenario where D-dimers may be of significance. They may also become an important biomarker in coronary and carotid artery atherosclerosis and aortic diseases. Being a non-invasive and quick means of diagnosis, D-dimers are a cost-effective tool used for diagnosing diseases. With the future being steered in the direction of preventive cardiology, it is imperative for clinicians to understand how to effectively utilize biomarkers in order to diagnose disorders. In this context, we review D-dimer's origin, current clinical utility, and potential future applications.

Effect of Chronic Blood Transfusion on Biomarkers of Coagulation Activation and Thrombin Generation in Sickle Cell Patients at Risk for Stroke

Hypercoagulability in sickle cell disease (SCD) is associated with multiple SCD phenotypes, association with stroke risk has not been well described. We hypothesized that serum levels of biomarkers of coagulation activation correlate with high transcranial Doppler ultrasound velocity and decreases with blood transfusion therapy in SCD patients. Stored serum samples from subjects in the Stroke Prevention in Sickle Cell Anemia (STOP) trial were analyzed using ELISA and protein multiplexing techniques. 40 subjects from each treatment arm (Standard Care [SC] and Transfusion [Tx]) at three time points—baseline, study exit and one year post-trial and 10 each of age matched children with SCD but normal TCD (SNTCD) and with normal hemoglobin (HbAA) were analyzed. At baseline, median vWF, TAT and D-dimer levels were significantly higher among STOP subjects than either HbAA or SNTCD. At study exit, median hemoglobin level was significantly higher while median TCD velocity was significantly lower in Tx compared to SC subjects. Median vWF (409.6 vs. 542.9 μg/ml), TAT (24.8 vs. 40.0 ng/ml) and D-dimer (9.2 vs. 19.1 μg/ml) levels were also significantly lower in the Tx compared to the SC group at study exit. Blood levels of biomarkers coagulation activation/thrombin generation correlated positively with TCD velocity and negatively with number of blood transfusions. Biomarkers of coagulation activation/thrombin generation were significantly elevated in children with SCD, at high risk for stroke. Reduction in levels of these biomarkers correlated with reduction in stroke risk (lower TCD velocity), indicating a possible role for hypercoagulation in SCD associated stroke.

Predictive Value of D-Dimer Levels and Tissue Doppler Mitral Annular Systolic Velocity for Detection of Left Atrial Appendage Thrombus in Patients with Mitral Stenosis in Sinus Rhythm

BACKGROUND

Transesophageal echocardiogram (TEE) is a gold standard test for diagnosis of left atrial (LA) thrombus, but it has limited sensitivity for identification of small thrombi within side lobes. Thus, the absence of visualizing a left atrial appendage (LAA) thrombus does not equate with the absence of a LAA thrombus.

AIM

To assess the predictive value of mitral annular systolic velocity (Sa) and D-dimer for the detection of LA thrombus and spontaneous echocardiographic contrast (SEC) in mitral stenosis (MS) patients with sinus rhythm (SR).

METHODS

Transthoracic echocardiogram, TEE, and D-dimer analysis were performed in 104 severe MS patients and divided them into three groups: Group I:no LA thrombus or SEC; Group II:LA SEC only; and Group III:LA thrombus.

RESULTS

Group III had more severe New York Heart Association (NYHA) class (III-IV) dyspnea and lower Sa (6.9 ± 0.7 vs.10.0 ± 1.2 cm/sec), lower LAA late emptying velocity (17.7 ± 2.1 vs. 24.4 ± 4.2 cm/sec), larger LA transverse dimension, and LAA area (LAAA) than group I+II. Mean D-dimer levels were higher in groups III and II than in group I. In multivariate analysis Sa, D-dimer levels, LAAA, and NYHA class were independent predictors of LA thrombus. ROC curve analysis revealed that higher Sa >8 cm/sec and lower D-dimer levels <370 μg/L predict the absence of LA thrombus and lower Sa <8 cm/sec and higher D-dimer levels >510 μg/L predict the presence of LA thrombus.

CONCLUSION

Measurement of Sa and D-dimer levels is necessary for better assessment of LA thrombus and SEC, for identification of patients who are at high risk for LA thrombus formation and for initiation of prophylactic anticoagulation.

Novel cardiovascular risk markers in women with ischaemic heart disease

Abstract

The incidence of coronary heart disease in premenopausal women is lower than in men because of their hormonal protection. Angina pectoris occurs in women about 10 years later than in men. However, mortality from ischaemic heart disease remains higher in women than in men. Current studies are focusing on novel cardiovascular risk biomarkers because it seems that traditional cardiovascular risk factors and their assessment scores underestimate the risk in females. Increased plasma levels of these newly established biomarkers of risk have been found to worsen endothelial dysfunction and inflammation, both of which play a key role in the pathogenesis of microvascular angina, which is very common in women. These novel cardiovascular risk markers can be classified into three categories: inflammatory markers, markers of haemostasis, and other biomarkers.

Life-Course Partnership Status and Biomarkers in Midlife: Evidence From the 1958 British Birth Cohort

OBJECTIVES

We examined the association between trajectories of partnership status over the life course and objectively measured health indicators in midlife.

METHODS

We used data from 4 waves (1981, 1991, 2000, and 2002-2004) of the British National Child Development Study (NCDS), a prospective cohort study that includes all people born in Britain during 1 week in March 1958 (n = 18 558).

RESULTS

After controlling for selection attributable to early-life and early-adulthood characteristics, we found that life-course trajectories of partnership status were associated with hemostatic and inflammatory markers, the prevalence of metabolic syndrome and respiratory function in midlife. Never marrying or cohabiting was negatively associated with health in midlife for both genders, but the effect was more pronounced in men. Women who had married in their late 20s or early 30s and remained married had the best health in midlife. Men and women in cohabiting unions had midlife health outcomes similar to those in formal marriages.

CONCLUSIONS

Partnership status over the life course has a cumulative effect on a wide range of objectively measured health indicators in midlife.

Effective components of Panax quinquefolius and Corydalis tuber protect the myocardium by inhibiting platelet activation and improving the hypercoagulable state

The aim of the present study was to investigate the effects of extract of Panax quinquefolius and Corydalis tuber (EPC) on platelet activation and the hypercoagulable state in rats with acute myocardial infarction (AMI). The MI model in Wistar rats was induced by coronary artery ligation. Sham surgery was performed as a control. The surviving rats that underwent MI surgery were divided into control (administered normal saline), metoprolol (9 mg/kg) and low-, moderate- and high-dose EPC groups (0.54, 1.08 g/kg and 2.16 g/kg, respectively). Saline, metoprolol and EPC were administered by gastrogavage for two consecutive weeks. The morphological changes of the myocardium were assessed by hematoxylin and eosin and nitroblue tetrazolium staining. Serum von Willebrand factor (vWF), D-dimer (DD), platelet membrane glycoproteins IIb-IIIa (GPIIb-IIIa) and CD62P levels were assessed using enzyme-linked immunosorbent assay. EPC attenuated the pathological changes of the myocardium. High-dose EPC decreased the serum concentration of vWF when compared with control group. Moderate and high doses of EPC decreased the DD and GPIIb-IIIa levels, and the CD62P level was gradually decreased with EPC dose escalation. The results therefore demonstrated that EPC protects the myocardium by inhibiting platelet activation and improving the hypercoagulable state in a rat model of AMI.

Association of markers of hemostasis with death in HIV-infected women

: In HIV negatives, markers of hemostasis, including D-dimer, factor VIII, plasminogen activator inhibitor-1 antigen (PAI-1), and total protein S are associated with all-cause and cardiovascular disease mortality. In HIV positives, studies of D-dimer and factor VIII with death were limited to short follow-up; associations of PAI-1 and total protein S with death have not been examined. In 674 HIV-infected women from the Women's Interagency HIV Study, markers from the first visit after enrollment were exposures of interest in multivariate analyses of death (AIDS and non-AIDS) in separate models at 5 and 16 years. There were 87 AIDS and 44 non-AIDS deaths at 5 years, and 159 AIDS and 113 non-AIDS deaths at 16 years. An inverse association of total protein S quartiles with non-AIDS deaths was observed at 5 (P trend = 0.002) and 16 years (P trend = 0.02); there was no association with AIDS deaths. The third quartile of PAI-1 was associated with AIDS deaths at 5 [hazard ratio (HR) = 4.0; 95% confidence interval (CI): 1.9 to 8.4] and 16 years (HR = 3.4; 95% CI: 1.9 to 5.9); and with non-AIDS deaths at 5 years (HR = 4.8; 95% CI: 1.6 to 13.9). D-dimer and factor VIII were not associated with AIDS or non-AIDS death at 5 or 16 years. Lower total Protein S was a consistent marker of non-AIDS death. We found no association between D-dimer with AIDS or non-AIDS death, in contrast to previous studies showing increased short-term (<5 years) mortality, which may represent sex differences or population heterogeneity. Given longer survival on highly active antiretroviral therapy, further studies of these markers are needed to determine their prognostic value.

Glucose transporter 1-expressing proinflammatory monocytes are elevated in combination antiretroviral therapy-treated and untreated HIV+ subjects

Monocyte activation during HIV-1 infection is associated with increased plasma levels of inflammatory markers and increased risk for premature development of age-related diseases. Because activated monocytes primarily use glucose to support cellular metabolism, we hypothesized that chronic monocyte activation during HIV-1 infection induces a hypermetabolic response with increased glucose uptake. To test this hypothesis, we evaluated glucose transporter 1 (Glut1) expression and glucose uptake by monocyte subpopulations in HIV-seropositive (HIV(+)) treatment-naive individuals (n = 17), HIV(+) individuals on combination antiretroviral therapy with viral loads below detection (n = 11), and HIV-seronegative (HIV(-)) individuals (n = 16). Surface expression of Glut1 and cellular uptake of the fluorescent glucose analog 2-(N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino)-2 deoxyglucose were analyzed by flow cytometry on monocyte subpopulations. Irrespective of treatment status, monocytes from HIV(+) persons had significantly increased surface expression of Glut1 compared with those from HIV(-) controls. Nonclassical (CD14(+)CD16(++)) and intermediate (CD14(++)CD16(+)) monocyte subpopulations showed higher Glut1 expression than did classical (CD14(++)CD16(-)) monocytes. Intermediate monocytes from treatment-naive HIV(+) individuals also showed increased uptake of 2-(N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino)-2 deoxyglucose compared with those from HIV(-) controls. Our results show that HIV infection is associated with increased glucose metabolism in monocytes and that Glut1 expression by proinflammatory monocytes is a potential marker of inflammation in HIV-infected subjects. However, the possibility exists whereby other Gluts such as Glut3 and Glut4 may also support the influx of glucose into activated and inflammatory monocyte populations.

Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy men

Flavanoid-rich dark chocolate consumption benefits cardiovascular health, but underlying mechanisms are elusive. We investigated the acute effect of dark chocolate on the reactivity of prothrombotic measures to psychosocial stress. Healthy men aged 20-50 years (mean ± SD: 35.7 ± 8.8) were assigned to a single serving of either 50 g of flavonoid-rich dark chocolate (n=31) or 50 g of optically identical flavonoid-free placebo chocolate (n=34). Two hours after chocolate consumption, both groups underwent an acute standardised psychosocial stress task combining public speaking and mental arithmetic. We determined plasma levels of four stress-responsive prothrombotic measures (i. e., fibrinogen, clotting factor VIII activity, von Willebrand Factor antigen, fibrin D-dimer) prior to chocolate consumption, immediately before and after stress, and at 10 minutes and 20 minutes after stress cessation. We also measured the flavonoid epicatechin, and the catecholamines epinephrine and norepinephrine in plasma. The dark chocolate group showed a significantly attenuated stress reactivity of the hypercoagulability marker D-dimer (F=3.87, p=0.017) relative to the placebo chocolate group. Moreover, the blunted D-dimer stress reactivity related to higher plasma levels of the flavonoid epicatechin assessed before stress (F=3.32, p = 0.031) but not to stress-induced changes in catecholamines (p's=0.35). There were no significant group differences in the other coagulation measures (p's≥0.87). Adjustments for covariates did not alter these findings. In conclusion, our findings indicate that a single consumption of flavonoid-rich dark chocolate blunted the acute prothrombotic response to psychosocial stress, thereby perhaps mitigating the risk of acute coronary syndromes triggered by emotional stress.

Update on the NCEP ATP-III emerging cardiometabolic risk factors

The intent of this review is to update the science of emerging cardiometabolic risk factors that were listed in the National Cholesterol Education Program (NCEP) Adult Treatment Panel-III (ATP-III) report of 2001 (updated in 2004). At the time these guidelines were published, the evidence was felt to be insufficient to recommend these risk factors for routine screening of cardiovascular disease risk. However, the panel felt that prudent use of these biomarkers for patients at intermediate risk of a major cardiovascular event over the subsequent 10 years might help identify patients who needed more aggressive low density lipoprotein (LDL) or non-high density lipoprotein (HDL) cholesterol lowering therapy. While a number of other emerging risk factors have been identified, this review will be limited to assessing the data and recommendations for the use of apolipoprotein B, lipoprotein (a), homocysteine, pro-thrombotic factors, inflammatory factors, impaired glucose metabolism, and measures of subclinical atherosclerotic cardiovascular disease for further cardiovascular disease risk stratification.

Predictive value of elevated D-dimer in patients undergoing primary angioplasty for ST elevation myocardial infarction

The aim of this study was to evaluate the prognostic value of D-dimer in patients with STEMI undergoing primary percutaneous coronary intervention (PCI). The prognostic value of D-dimer has been documented in patients with acute coronary syndrome without ST-segment elevation. However, its value in acute ST-segment elevation myocardial infarction (STEMI) remains unclear. We prospectively enrolled 453 consecutive STEMI patients (mean age 55.6 ± 12.4 years, 364 male, 89 female) undergoing primary PCI. The study population was divided into tertiles based on admission D-dimer values. The high D-dimer group (n = 151) was defined as a value in the third tertile [>0.72 ug/ml fibrinogen equivalent units (FEU)], and the low D-dimer group (n = 302) included those patients with a value in the lower two tertiles (≤0.72 ug/ml FEU). Clinical characteristics, in-hospital and 6-month outcomes of primary PCI were analyzed. The patients of the high D-dimer group were older (mean age 60.1 ± 13.5 versus 52.4 ± 10.6, P < 0.001). Higher in-hospital cardiovascular mortality and 6-month all-cause mortality rates were observed in the high D-dimer group (7.2 versus 0.6%, P < 0.001 and 13.9 versus 2%, P < 0.001, respectively). In Cox multivariate analysis; a high admission D-dimer value (>0.72 ug/ml FEU) was found to be a powerful independent predictor of 6-month all-cause mortality (odds ratio: 10.1, 95% confidence interval: 1.24-42.73, P = 0.03). These results suggest that a high admission D-dimer, level was associated with increased in-hospital cardiovascular mortality and 6-month all-cause mortality in patients with STEMI undergoing primary PCI.

Lifecourse social position and D-dimer; findings from the 1958 British birth cohort

The aim is to examine the association of lifecourse socioeconomic position (SEP) on circulating levels of D-dimer. Data from the 1958 British birth cohort were used, social class was determined at three stages of respondents' life: at birth, at 23 and at 42 years. A cumulative indicator score of SEP (CIS) was calculated ranging from 0 (always in the highest social class) to 9 (always in the lowest social class). In men and women, associations were observed between CIS and D-dimer (P<0.05). Thus, the respondents in more disadvantaged social classes had elevated levels of D-dimer compared to respondents in less disadvantaged social class. In multivariate analyses, the association of disadvantaged social position with D-dimer was largely explained by fibrinogen, C-reactive protein and von Willebrand Factor in women, and additionally by smoking, alcohol consumption and physical activity in men. Socioeconomic circumstances across the lifecourse at various stages also contribute independently to raised levels of D-dimer in middle age in women only. Risk exposure related to SEP accumulates across life and contributes to raised levels of D-dimer. The association of haemostatic markers and social differences in health may be mediated by inflammatory and other markers.