Macrophage migration inhibitory factor and the risk of myocardial infarction or death due to coronary artery disease in adults without prior myocardial infarction or stroke: the EPIC-Norfolk Prospective Population study

ANGPTL3 (Angiopoietin-Like 3) Preferentially Resides on High-Density Lipoprotein in the Human Circulation, Affecting Its Activity

Background ANGPTL3 (angiopoietin-like protein 3) is an acknowledged crucial regulator of lipid metabolism by virtue of its inhibitory effect on lipoprotein lipase and endothelial lipase. It is currently unknown whether and to which lipoproteins ANGPTL3 is bound and whether the ability of ANGPTL3 to inhibit lipase activity is affected by binding to lipoproteins. Methods and Results Incubation of ultracentrifugation-isolated low-density lipoprotein (LDL) and high-density lipoprotein (HDL) fractions from healthy volunteers with recombinant ANGPTL3 revealed that ANGPTL3 associates with both HDL and LDL particles ex vivo. Plasma from healthy volunteers and a patient deficient in HDL was fractionated by fast protein liquid chromatography, and ANGPTL3 distribution among lipoprotein fractions was measured. In healthy volunteers, ≈75% of lipoprotein-associated ANGPTL3 resides in HDL fractions, whereas ANGPTL3 was largely bound to LDL in the patient deficient in HDL. ANGPTL3 activity was studied by measuring lipolysis and uptake of 3H-trioleate by brown adipocyte T37i cells. Unbound ANGPTL3 did not suppress lipase activity, but when given with HDL or LDL, ANGPTL3 suppressed lipase activity by 21.4±16.4% (P=0.03) and 25.4±8.2% (P=0.006), respectively. Finally, in a subset of the EPIC (European Prospective Investigation into Cancer) Norfolk study, plasma HDL cholesterol and amount of large HDL particles were both positively associated with plasma ANGPTL3 concentrations. Moreover, plasma ANGPTL3 concentrations showed a positive association with incident coronary artery disease (odds ratio, 1.25 [95% CI, 1.01-1.55], P=0.04). Conclusions Although ANGPTL3 preferentially resides on HDL, its activity was highest once bound to LDL particles.

Genetic Variation of Migration Inhibitory Factor Gene rs2070766 Is Associated With Acute Coronary Syndromes in Chinese Population

Genetic variation of macrophage migration inhibitory factor (MIF) gene has been linked to coronary artery disease. We investigated an association between the polymorphism of MIF gene rs2070766 and acute coronary syndromes (ACS) and the predictive value of MIF gene variation in clinical outcomes. This study involved in 963 ACS patients and 932 control subjects from a Chinese population. All participants were genotyped for the single nucleotide polymorphism (SNP) of MIF gene rs2070766 using SNPscan™. A nomogram model using MIF genetic variation and clinical variables was established to predict risk of ACS. Major adverse cardiovascular events (MACE) were monitored during a follow-up period. The frequency of rs2070766 GG genotype was higher in ACS patients than in control subjects (6.2 vs 3.8%, p = 0.034). Multivariate logistic regression analysis revealed that individuals with mutant GG genotype had a 1.7-fold higher risk of ACS compared with individuals with CC or CG genotypes. Using MIF rs2070766 genotypes and clinical factors, we developed a nomogram model to predict risk of ACS. The nomogram model had a good discrimination with an area under the curve of 0.781 (95% CI: 0.759-0.804), concordance index of 0.784 (95% CI: 0.762-0.806) and well-fitted calibration. During the follow-up period of 25 months, Kaplan-Meier curves demonstrated that ACS patients carrying GG phenotype developed more MACE compared to CC or CG carriers (p < 0.05). GG genotype of MIF gene rs2070766 was associated with a higher risk of ACS in a Chinese population. The GG genotype carriers in ACS patients had worse clinical outcomes compared with those carrying CC or CG genotype. Together with rs2070766 genetic variant of MIF gene, we established a novel nomogram model that can provide individualized prediction for ACS.

Circulating MIF Levels Predict Clinical Outcomes in Patients With ST-Elevation Myocardial Infarction After Percutaneous Coronary Intervention

BACKGROUND

The purpose of the study was to assess the value of admission macrophage migration inhibitory factor (MIF) levels in predicting clinical outcomes in ST-elevation myocardial infarction (STEMI) patients.

METHODS

For this study we recruited 498 STEMI patients after they received percutaneous coronary intervention (PCI), 40 with stable angina pectoris and 137 healthy participants. Plasma MIF levels were measured at admission and after PCI. The primary end points were in-hospital mortality and major adverse cardio-and/or cerebrovascular events (MACCE) during hospitalization and 3.2-year follow-up period.

RESULTS

Admission MIF levels were elevated in 88.4% of STEMI patients over the upper reference limit of healthy controls and it was 3- to 7-fold higher than that in stable angina pectoris and control groups (122 ± 61 vs 39 ± 19 vs 17 ± 8 ng/mL; P < 0.001). Admission MIF levels were significantly higher in patients who died after myocardial infarction vs survivors. For predicting in-hospital mortality using the optimal cutoff value (127.8 ng/mL) of MIF, the area under the receiver operating characteristic curve for MIF was 0.820, similar area under the receiver operating characteristic curve values for predicting short-term outcomes were observed for high-sensitivity troponin T, CK-MB, N-terminal probrain natriuretic peptide, and Global Registry of Acute Coronary Events (GRACE) score. Although peak high-sensitivity troponin T and N-terminal probrain natriuretic peptide also predicted MACCE during the follow-up period, only higher admission MIF levels predicted in-hospital mortality and MACCE during the 3.2-year follow-up. Multivariate regression analysis showed the independent predictive value of a higher admission MIF level (≥ 127.8 ng/mL) on in-hospital mortality (odds ratio, 9.1; 95% confidence interval, 1.7-47.2) and 3.2-year MACCE (hazard ratio, 2.8; 95% confidence interval, 1.5-5.6).

CONCLUSIONS

A higher admission MIF level is an independent predictor for in-hospital mortality and long-term MACCE in STEMI patients who underwent PCI.

Relationship of lipoprotein-associated apolipoprotein C-III with lipid variables and coronary artery disease risk: The EPIC-Norfolk prospective population study

BACKGROUND

Plasma apolipoprotein C-III (apoC-III) levels are associated with coronary artery disease (CAD) risk.

OBJECTIVE

To assess whether lipoprotein-associated apoC-III levels predict risk of CAD events.

METHODS

apoC-III associated with apoB, apoAI, and Lp(a) (apoCIII-apoB, apoCIII-apoAI, and apoCIII-Lp(a), respectively) were measured using high-throughput chemiluminescent enzyme-linked immunoassays in 2711 subjects (1879 controls and 832 cases with CAD) in the European Prospective Investigation into Cancer and Nutrition-Norfolk prospective population study with 7.4 years of follow-up. These measures were correlated with a variety of lipid measurements and the presence of CAD. The indices of "total apoCIII-apoB" and "total apoCIII-apoAI" were derived by multiplying plasma apoB and apoAI, respectively.

RESULTS

apoCIII-apoB (P = .001), apoCIII-Lp(a) (P < .001), apoCIII-apoAI (P = .005) were higher in cases vs controls; tended to correlate positively with body mass index, hsCRP, apoC-III, low-density lipoprotein (LDL) cholesterol, triglycerides, remnant cholesterol, very low density lipoprotein, LDL and high-density lipoprotein particle number and very low density lipoprotein size; but negatively with LDL and high-density lipoprotein particle size (P < .001 for all). apoCIII-apoB, apoCIII-apoAI, apoCIII-Lp(a), total apoCIII-Lp(a), and total apoCIII-apoB were predictors of CAD after adjustment of age, sex, body mass index, smoking, diabetes, hypertensive and lipid-lowering drug use, but they lost their significance after further adjustment of lipid and lipoprotein variables.

CONCLUSIONS

This study suggests that enzyme-linked immunoassay-measured lipoprotein-associated apoC-III markers reflect atherogenic lipid particles but do not independently predict risk of CAD events.

The influence of low-grade inflammation on platelets in patients with stable coronary artery disease

Inflammation is likely to be involved in all stages of atherosclerosis. Numerous inflammatory biomarkers are currently being studied, and even subtle increases in inflammatory biomarkers have been associated with increased risk of cardiovascular events in patients with coronary artery disease (CAD). Low-grade inflammation may influence both platelet production and platelet activation potentially leading to enhanced platelet aggregation. Thrombopoietin is considered the primary regulator of platelet production, but it likely acts in conjunction with numerous cytokines, of which many have altered levels in CAD. Previous studies have shown that high-sensitive C-reactive protein (CRP) independently predicts increased platelet aggregation in stable CAD patients. Increased levels of CRP, fibrinogen, interleukin-6, stromal cell-derived factor-1, CXC motif ligand 16, macrophage migration inhibitory factor, RANTES, calprotectin, and copeptin have been associated with increased risk of cardiovascular events in CAD patients. Additionally, some of these inflammatory markers have been associated with enhanced platelet activation and aggregation. However, CRP and other inflammatory markers provide only limited additional predictive value to classical risk factors such as smoking, blood pressure, and cholesterol levels. Existing data do not clarify whether inflammation simply accompanies CAD and increased production and aggregation of platelets, or whether a causal relationship exists. In this review, we provide a comprehensive overview of inflammatory markers in stable CAD with particular emphasis on platelet production, activation, and aggregation in CAD patients.

Association of High-Density Lipoprotein-Cholesterol Versus Apolipoprotein A-I With Risk of Coronary Heart Disease: The European Prospective Investigation Into Cancer-Norfolk Prospective Population Study, the Atherosclerosis Risk in Communities Study, and the Women's Health Study

Background

The contribution of apolipoprotein A‐I (apoA‐I) to coronary heart disease (CHD) risk stratification over and above high‐density lipoprotein cholesterol (HDL‐C) is unclear. We studied the associations between plasma levels of HDL‐C and apoA‐I, either alone or combined, with risk of CHD events and cardiovascular risk factors among apparently healthy men and women.

Methods and Results

HDL‐C and apoA‐I levels were measured among 17 661 participants of the EPIC (European Prospective Investigation into Cancer)‐Norfolk prospective population study. Hazard ratios for CHD events and distributions of risk factors were calculated by quartiles of HDL‐C and apoA‐I. Results were validated using data from the ARIC (Atherosclerosis Risk in Communities) and WHS (Women's Health Study) cohorts, comprising 15 494 and 27 552 individuals, respectively. In EPIC‐Norfolk, both HDL‐C and apoA‐I quartiles were strongly and inversely associated with CHD risk. Within HDL‐C quartiles, higher apoA‐I levels were not associated with lower CHD risk; in fact, CHD risk was higher within some HDL‐C quartiles. ApoA‐I levels were associated with higher levels of CHD risk factors: higher body mass index, HbA1c, non‐HDL‐C, triglycerides, apolipoprotein B, systolic blood pressure, and C‐reactive protein, within fixed HDL‐C quartiles. In contrast, HDL‐C levels were consistently inversely associated with overall CHD risk and CHD risk factors within apoA‐I quartiles (P<0.001). These findings were validated in the ARIC and WHS cohorts.

Conclusions

Our findings demonstrate that apoA‐I levels do not offer predictive information over and above HDL‐C. In fact, within some HDL‐C quartiles, higher apoA‐I levels were associated with higher risk of CHD events, possibly because of the unexpected higher prevalence of cardiovascular risk factors in association with higher apoA‐I levels.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00000479.

The Dutch SCORE-based risk charts seriously underestimate the risk of cardiovascular disease

Introduction

Dutch cardiovascular disease (CVD) prevention guidelines recommend the use of modified SCORE risk charts to estimate 10-year risk of fatal and nonfatal CVD (myocardial infarction, cerebrovascular disease and congestive heart failure). This combined risk is derived from the SCORE mortality risk using multipliers. These multipliers have been shown to underestimate overall CVD risk. We aimed to compare the current Dutch risk charts with charts that estimate a broader range of clinically relevant CVD using updated multipliers.

Methods

We constructed new risk charts for 10-year CVD using updated, recently published multipliers from the EPIC-Norfolk study, based on ratios of fatal CVD to clinically relevant CVD (fatal plus nonfatal CVD requiring hospitalisation for ischaemic heart disease, cardiac failure, cerebrovascular disease, peripheral artery disease, and aortic aneurysm). Our primary outcome was the proportion of the three risk categories, i. e. ‘high risk’ (>20% 10-year risk), ‘intermediate risk’ (10–19%) and ‘low risk’ (<10%) in the new risk charts as compared with the current risk charts.

Results

Applying the updated fatal CVD/clinical CVD multipliers led to a marked increase in the high-risk categories (109 (27%) vs. 244 (61%), (p < 0.001)), an absolute increase of 229%. Similarly, the number of low-risk categories decreased (190 (48%) vs. 81 (20%) (p < 0.001)).

Conclusion

The current Dutch risk charts seriously underestimate the risk of clinical CVD, even in the first 10 years. Even when analyses are restricted to CVD events that required hospitalisation, true 10-year risks are more than double the currently estimated risks. Future guidelines may be revised to reflect these findings.

Carriers of the PCSK9 R46L Variant Are Characterized by an Antiatherogenic Lipoprotein Profile Assessed by Nuclear Magnetic Resonance Spectroscopy-Brief Report

OBJECTIVE

Carriers of the PCSK9 (proprotein convertase subtilisin/kexin 9) R46L genetic variant (rs11591147) are characterized by low levels of low-density lipoprotein cholesterol and a decreased risk of cardiovascular disease. We studied the impact of the R46L variant on lipoprotein size and composition.

APPROACH AND RESULTS

Lipoprotein size and composition were measured by nuclear magnetic resonance spectroscopy in 2373 participants of the EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk study. After adjusting for age, sex, and cardiovascular disease status, carriers of the R46L variant (n=77) were characterized by lower concentrations of very low-density lipoprotein particles (85.8±26.2 versus 99.0±33.3 nmol/L; P<0.001), low-density lipoprotein particles (1479.7±396.8 versus 1662.9±458.3 nmol/L; P<0.001), and lipoprotein(a) (11.1 [7.2-28.6] versus 12.4 [6.7-29.1] mg/dL; P<0.001) compared with noncarriers. Total high-density lipoprotein particle and very low-density lipoprotein, low-density lipoprotein, and high-density lipoprotein particle sizes were comparable in carriers and noncarriers. Carriers were characterized by lower secretory phospholipase A2 (4.2±0.9 versus 4.6±1.3 nmol/mL/min; P=0.004) and lipoprotein-associated phospholipase A2 activity (47.5±14.1 versus 52.4±16.2 nmol/mL/min; P=0.02) compared with noncarriers.

CONCLUSIONS

Results of this study suggest that carriers of the PCSK9 R46L genetic variant have lower very low-density lipoprotein and low-density lipoprotein particle concentrations, lower lipoprotein(a) levels, and lower secretory phospholipase A2 and lipoprotein-associated phospholipase A2 activity compared with noncarriers.

Topical Beta-Blockers and Cardiovascular Mortality: Systematic Review and Meta-Analysis with Data from the EPIC-Norfolk Cohort Study

Purpose: To determine if topical beta-blocker use is associated with increased cardiovascular mortality, particularly among people with self-reported glaucoma.

Methods: All participants who participated in the first health check (N = 25,639) of the European Prospective Investigation into Cancer (EPIC) Norfolk cohort (1993–2013) were included in this prospective cohort study, with a median follow-up of 17.0 years. We determined use of topical beta-blockers at baseline through a self-reported questionnaire and prescription check at the first clinical visit. Cardiovascular mortality was ascertained through data linkage with the Office for National Statistics mortality database. Hazard ratios (HRs) were estimated using multivariable Cox regression models. Meta-analysis of the present study’s results together with other identified literature was performed using a random effects model.

Results: We did not find an association between the use of topical beta-blockers and cardiovascular mortality (HR 0.93, 95% confidence interval, CI, 0.67–1.30). In the 514 participants with self-reported glaucoma, no association was found between the use of topical beta-blockers and cardiovascular mortality (HR 0.89, 95% CI 0.56–1.40). In the primary meta-analysis of four publications, there was no evidence of an association between the use of topical beta-blockers and cardiovascular mortality (pooled HR estimate 1.10, 95% CI 0.84–1.36).

Conclusion: Topical beta-blockers do not appear to be associated with excess cardiovascular mortality. This evidence does not indicate that a change in current practice is warranted, although clinicians should continue to assess individual patients and their cardiovascular risk prior to commencing topical beta-blockers.

Population and assay thresholds for the predictive value of lipoprotein (a) for coronary artery disease: the EPIC-Norfolk Prospective Population Study

Variable agreement exists between different lipoprotein (a) [Lp(a)] measurement methods, but their clinical relevance remains unclear. The predictive value of Lp(a) measured by two different assays [Randox and University of California, San Diego (UCSD)] was determined in 623 coronary artery disease (CAD) cases and 948 controls in a case-control study within the EPIC-Norfolk Prospective Population Study. Participants were divided into sex-specific quintiles, and by Lp(a) <50 versus ∼50 mg/dl, which represents the 80th percentile in northern European subjects. Randox and UCSD Lp(a) levels were strongly correlated; Spearman's correlation coefficients for men, women, and sexes combined were 0.905, 0.915, and 0.909, respectively (P< 0.001 for each). The >80th percentile cutoff values, however, were 36 mg/dl and 24 mg/dl for the Randox and UCSD assays, respectively. Despite this, Lp(a) levels were significantly associated with CAD risk, with odds ratios of 2.18 (1.58-3.01) and 2.35 (1.70-3.26) for people in the top versus bottom Lp(a) quintile for the Randox and UCSD assays, respectively. This study demonstrates that CAD risk is present at lower Lp(a) levels than the currently suggested optimal Lp(a) level of <50 mg/dl. Appropriate thresholds may need to be population and assay specific until Lp(a) assays are standardized and Lp(a) thresholds are evaluated broadly across all populations at risk for CVD and aortic stenosis.

Repeat Cardiovascular Risk Assessment after Four Years: Is There Improvement in Risk Prediction?

Background

Framingham risk equations are widely used to predict cardiovascular disease based on health information from a single time point. Little is known regarding use of information from repeat risk assessments and temporal change in estimated cardiovascular risk for prediction of future cardiovascular events. This study was aimed to compare the discrimination and risk reclassification of approaches using estimated cardiovascular risk at single and repeat risk assessments

Methods

Using data on 12,197 individuals enrolled in EPIC-Norfolk cohort, with 12 years of follow-up, we examined rates of cardiovascular events by levels of estimated absolute risk (Framingham risk score) at the first and second health examination four years later. We calculated the area under the receiver operating characteristic curve (aROC) and risk reclassification, comparing approaches using information from single and repeat risk assessments (i.e., estimated risk at different time points).

Results

The mean Framingham risk score increased from 15.5% to 17.5% over a mean of 3.7 years from the first to second health examination. Individuals with high estimated risk (≥20%) at both health examinations had considerably higher rates of cardiovascular events than those who remained in the lowest risk category (<10%) in both health examinations (34.0 [95%CI 31.7–36.6] and 2.7 [2.2–3.3] per 1,000 person-years respectively). Using information from the most up-to-date risk assessment resulted in a small non-significant change in risk classification over the previous risk assessment (net reclassification improvement of -4.8%, p>0.05). Using information from both risk assessments slightly improved discrimination compared to information from a single risk assessment (aROC 0.76 and 0.75 respectively, p<0.001).

Conclusions

Using information from repeat risk assessments over a period of four years modestly improved prediction, compared to using data from a single risk assessment. However, this approach did not improve risk classification.

Heterogeneous impact of classic atherosclerotic risk factors on different arterial territories: the EPIC-Norfolk prospective population study

AIMS

Particular atherosclerotic risk factors may differ in their association with atherosclerosis across vascular territories. Few studies have compared the associations between multiple risk factors and cardiovascular disease (CVD) manifestations in one population. We studied the strength of the associations between traditional risk factors including coronary artery disease (CAD), ischaemic and haemorrhagic stroke, abdominal aortic aneurysms (AAAs), and peripheral arterial disease (PAD).

METHODS AND RESULTS

This analysis included 21 798 participants of the EPIC-Norfolk population study, without previous CVD. Events were defined as hospitalization or mortality, coded using ICD-10. The associations between the risk factors, such as low-density lipoprotein cholesterol, systolic blood pressure (SBP), and smoking, and the various CVD manifestations were compared using competing risk analyses. During 12.1 years, 3087 CVD events were recorded. The associations significantly differed across CVD manifestations. Low-density lipoprotein cholesterol was strongly associated with CAD [adjusted hazard rate (aHR) highest vs. lowest quartile 1.63, 95% CI 1.44-1.86]. Systolic blood pressure was a strong risk factor for PAD (aHR highest vs. lowest quartile 2.95, 95% CI 1.78-4.89) and ischaemic stroke (aHR highest vs. lowest quartile 2.48, 95% CI 1.55-3.97), but not for AAA. Smoking was strongly associated with incident AAA (aHR current vs. never 7.66, 95% CI 4.50-13.04) and PAD (aHR current vs. never 4.66, 95% CI 3.29-6.61), but not with haemorrhagic stroke.

CONCLUSION

The heterogeneity in the risk factor-CVD associations supports the concept of pathophysiological differences between atherosclerotic CVD manifestations and could have implications for CVD prevention.

Chemokines and their receptors in Atherosclerosis

Atherosclerosis, a chronic inflammatory disease of the medium- and large-sized arteries, is the main underlying cause of cardiovascular diseases (CVDs) most often leading to a myocardial infarction or stroke. However, atherosclerosis can also develop without this clinical manifestation. The pathophysiology of atherosclerosis is very complex and consists of many cells and molecules interacting with each other. Over the last years, chemokines (small 8-12 kDa cytokines with chemotactic properties) have been identified as key players in atherogenesis. However, this remains a very active and dynamic field of research. Here, we will give an overview of the current knowledge about the involvement of chemokines in all phases of atherosclerotic lesion development. Furthermore, we will focus on two chemokines that recently have been associated with atherogenesis, CXCL12, and macrophage migration inhibitory factor (MIF). Both chemokines play a crucial role in leukocyte recruitment and arrest, a critical step in atherosclerosis development. MIF has shown to be a more pro-inflammatory and thus pro-atherogenic chemokine, instead CXCL12 seems to have a more protective function. However, results about this protective role are still quite debatable. Future research will further elucidate the precise role of these chemokines in atherosclerosis and determine the potential of chemokine-based therapies.

Estimated 10-year cardiovascular mortality seriously underestimates overall cardiovascular risk

OBJECTIVE

The European Society of Cardiology's prevention guideline suggests that the risk of total (fatal plus non-fatal) cardiovascular disease (CVD) may be calculated from the risk of CVD mortality using a fixed multiplier (3×). However, the proposed multiplier has not been validated. We investigated the ratio of total CVD to CVD mortality in a large population-based cohort.

METHODS

CVD mortality and total CVD (fatal plus non-fatal CVD requiring hospitalisation) were analysed using Kaplan-Meier estimates among 24 014 men and women aged 39-79 years without baseline CVD or diabetes mellitus in the prospective population-based European Prospective Investigation of Cancer and Nutrition-Norfolk cohort. CVD outcomes included death and hospitalisations for ischaemic heart disease, heart failure, cerebrovascular disease, peripheral artery disease or aortic aneurysm. The main study outcome was the ratio of 10-year total CVD to 10-year CVD mortality stratified by age and sex.

RESULTS

Ten year CVD mortality was 3.9% (900 CVD deaths, 95% CI 3.6% to 4.1%); the rate of total CVD outcomes was 21.2% (4978 fatal or non-fatal CVD outcomes, 95% CI 20.7% to 21.8%). The overall ratio of total CVD to CVD mortality was 5.4. However, we found major differences in this ratio when stratified by gender and age. In young women (39-50 years), the ratio of total CVD to CVD mortality was 28.5, in young men (39-50 years) 11.7. In the oldest age group, these ratios were considerably lower (3.2 in women and 2.4 in men aged 75-79 years).

CONCLUSIONS

The relationship between 10-year total CVD and CVD mortality is dependent on age and sex, and cannot be estimated using a fixed multiplier. Using CVD mortality to estimate total CVD risk leads to serious underestimation of risk, particularly in younger age groups, and particularly in women.

MIF and CXCL12 in Cardiovascular Diseases: Functional Differences and Similarities

Coronary artery disease (CAD) as part of the cardiovascular diseases is a pathology caused by atherosclerosis, a chronic inflammatory disease of the vessel wall characterized by a massive invasion of lipids and inflammatory cells into the inner vessel layer (intima) leading to the formation of atherosclerotic lesions; their constant growth may cause complications such as flow-limiting stenosis and plaque rupture, the latter triggering vessel occlusion through thrombus formation. Pathophysiology of CAD is complex and over the last years many players have entered the picture. One of the latter being chemokines (small 8-12 kDa cytokines) and their receptors, known to orchestrate cell chemotaxis and arrest. Here, we will focus on the chemokine CXCL12, also known as stromal cell-derived factor 1 (SDF-1) and the chemokine-like function chemokine, macrophage migration-inhibitory factor (MIF). Both are ubiquitously expressed and highly conserved proteins and play an important role in cell homeostasis, recruitment, and arrest through binding to their corresponding chemokine receptors CXCR4 (CXCL12 and MIF), ACKR3 (CXCL12), and CXCR2 (MIF). In addition, MIF also binds to the receptor CD44 and the co-receptor CD74. CXCL12 has mostly been studied for its crucial role in the homing of (hematopoietic) progenitor cells in the bone marrow and their mobilization into the periphery. In contrast to CXCL12, MIF is secreted in response to diverse inflammatory stimuli, and has been associated with a clear pro-inflammatory and pro-atherogenic role in multiple studies of patients and animal models. Ongoing research on CXCL12 points at a protective function of this chemokine in atherosclerotic lesion development. This review will focus on the role of CXCL12 and MIF and their differences and similarities in CAD of high risk patients.

Habitual chocolate consumption and risk of cardiovascular disease among healthy men and women

OBJECTIVE

To examine the association between chocolate intake and the risk of future cardiovascular events.

METHODS

We conducted a prospective study using data from the European Prospective Investigation into Cancer (EPIC)-Norfolk cohort. Habitual chocolate intake was quantified using the baseline food frequency questionnaire (1993-1997) and cardiovascular end points were ascertained up to March 2008. A systematic review was performed to evaluate chocolate consumption and cardiovascular outcomes.

RESULTS

A total of 20,951 men and women were included in EPIC-Norfolk analysis (mean follow-up 11.3±2.8 years, median 11.9 years). The percentage of participants with coronary heart disease (CHD) in the highest and lowest quintile of chocolate consumption was 9.7% and 13.8%, and the respective rates for stroke were 3.1% and 5.4%. The multivariate-adjusted HR for CHD was 0.88 (95% CI 0.77 to 1.01) for those in the top quintile of chocolate consumption (16-99 g/day) versus non-consumers of chocolate intake. The corresponding HR for stroke and cardiovascular disease (cardiovascular disease defined by the sum of CHD and stroke) were 0.77 (95% CI 0.62 to 0.97) and 0.86 (95% CI 0.76 to 0.97). The propensity score matched estimates showed a similar trend. A total of nine studies with 157,809 participants were included in the meta-analysis. Higher compared to lower chocolate consumption was associated with significantly lower CHD risk (five studies; pooled RR 0.71, 95% CI 0.56 to 0.92), stroke (five studies; pooled RR 0.79, 95% CI 0.70 to 0.87), composite cardiovascular adverse outcome (two studies; pooled RR 0.75, 95% CI 0.54 to 1.05), and cardiovascular mortality (three studies; pooled RR 0.55, 95% CI 0.36 to 0.83).

CONCLUSIONS

Cumulative evidence suggests that higher chocolate intake is associated with a lower risk of future cardiovascular events, although residual confounding cannot be excluded. There does not appear to be any evidence to say that chocolate should be avoided in those who are concerned about cardiovascular risk.

Tinned fruit consumption and mortality in three prospective cohorts

Dietary recommendations to promote health include fresh, frozen and tinned fruit, but few studies have examined the health benefits of tinned fruit. We therefore studied the association between tinned fruit consumption and mortality. We followed up participants from three prospective cohorts in the United Kingdom: 22,421 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort (1993-2012), 52,625 participants from the EPIC-Oxford cohort (1993-2012), and 7440 participants from the Whitehall II cohort (1991-2012), all reporting no history of heart attack, stroke, or cancer when entering these studies. We estimated the association between frequency of tinned fruit consumption and all cause mortality (primary outcome measure) using Cox regression models within each cohort, and pooled hazard ratios across cohorts using random-effects meta-analysis. Tinned fruit consumption was assessed with validated food frequency questionnaires including specific questions about tinned fruit. During 1,305,330 person years of follow-up, 8857 deaths occurred. After adjustment for lifestyle factors and risk markers the pooled hazard ratios (95% confidence interval) of all cause mortality compared with the reference group of tinned fruit consumption less often than one serving per month were: 1.05 (0.99, 1.12) for one to three servings per month, 1.10 (1.03, 1.18) for one serving per week, and 1.13 (1.04, 1.23) for two or more servings per week. Analysis of cause-specific mortality showed that tinned fruit consumption was associated with mortality from cardiovascular causes and from non-cardiovascular, non-cancer causes. In a pooled analysis of three prospective cohorts from the United Kingdom self-reported tinned fruit consumption in the 1990s was weakly but positively associated with mortality during long-term follow-up. These findings raise questions about the evidence underlying dietary recommendations to promote tinned fruit consumption as part of a healthy diet.

Mass Spectrometric Immunoassay for the qualitative and quantitative analysis of the cytokine Macrophage Migration Inhibitory Factor (MIF)

Background

The cytokine MIF (Macrophage Migration Inhibitory Factor) has diverse physiological roles and is present at elevated concentrations in numerous disease states. However, its molecular heterogeneity has not been previously investigated in biological samples. Mass Spectrometric Immunoassay (MSIA) may help elucidate MIF post-translational modifications existing in vivo and provide additional clarity regarding its relationship to diverse pathologies.

Results

In this work, we have developed and validated a fully quantitative MSIA assay for MIF, and used it in the discovery and quantification of different proteoforms of MIF in serum samples, including cysteinylated and glycated MIF. The MSIA assay had a linear range of 1.56-50 ng/mL, and exhibited good precision, linearity, and recovery characteristics. The new assay was applied to a small cohort of human serum samples, and benchmarked against an MIF ELISA assay.

Conclusions

The quantitative MIF MSIA assay provides a sensitive, precise and high throughput method to delineate and quantify MIF proteoforms in biological samples.

Impact of counterbalance between macrophage migration inhibitory factor and its inhibitor Gremlin-1 in patients with coronary artery disease

OBJECTIVE

Monocyte infiltration is a critical step in the pathophysiology of plaque instability in coronary artery disease (CAD). Macrophage migration inhibitory factor (MIF) is involved in atherosclerotic plaque progression and instability leading to intracoronary thrombosis. Gremlin-1 (Grem1) has been recently identified as endogenous inhibitor of MIF. To date there are no data on the clinical impact of this interaction in cardiovascular patients.

METHODS AND RESULTS

Plasma levels of MIF and Grem1 were determined by enzyme-linked immunoassay in patients with acute coronary syndromes (ACS, n = 120; stable CAD, n = 166 and healthy control subjects, n = 25). MIF levels were significantly increased in ACS compared to stable CAD and healthy control (ACS: median 2.85; IQR 3.52 ng/ml; versus SAP: median 1.22; IQR 2.99 ng/ml; versus healthy control: median 0.10; IQR 0.09 ng/ml, p < 0.001). Grem1 levels were significantly higher in ACS and stable CAD patients compared to healthy control (ACS: median 211.00; IQR 130.47 ng/ml; SAP: median 220.20; IQR 120.93 ng/ml, versus healthy control: median 90.57; IQR 97.68 ng/ml, p < 0.001). Grem1/MIF ratio was independently associated with ACS, whereas the single parameters were not associated with the presence of ACS. Furthermore, Grem1/MIF ratio was associated with angiographic signs of intracoronary thrombi and severity of thrombus burden.

CONCLUSION

These novel findings suggest a potential role of Grem1/MIF ratio to indicate acuity of CAD and the grade of plaque stability. Prospective angiographic cohort studies involving plaque imaging techniques are warranted to further characterize the prognostic role of this novel risk marker in CAD patients.

Role of MIF in myocardial ischaemia and infarction: insight from recent clinical and experimental findings

First discovered in 1966 as an inflammatory cytokine, MIF (macrophage migration inhibitory factor) has been extensively studied for its pivotal role in a variety of inflammatory diseases, including rheumatoid arthritis and atherosclerosis. Although initial studies over a decade ago reported increases in circulating MIF levels following acute MI (myocardial infarction), the dynamic changes in MIF and its pathophysiological significance following MI have been unknown until recently. In the present review, we summarize recent experimental and clinical studies examining the diverse functions of MIF across the spectrum of acute MI from brief ischaemia to post-infarct healing. Following an acute ischaemic insult, MIF is rapidly released from jeopardized cardiomyocytes, followed by a persistent MIF production and release from activated immune cells, resulting in a sustained increase in circulating levels of MIF. Recent studies have documented two distinct actions of MIF following acute MI. In the supra-acute phase of ischaemia, MIF mediates cardioprotection via several distinct mechanisms, including metabolic activation, apoptosis suppression and antioxidative stress. In prolonged myocardial ischaemia, however, MIF promotes inflammatory responses with largely detrimental effects on cardiac function and remodelling. The pro-inflammatory properties of MIF are complex and involve MIF derived from cardiac and immune cells contributing sequentially to the innate immune response evoked by MI. Emerging evidence on the role of MIF in myocardial ischaemia and infarction highlights a significant potential for the clinical use of MIF agonists or antagonists and as a unique cardiac biomarker.

Macrophage migration inhibitory factor in myocardial ischaemia/reperfusion injury

Acute myocardial infarction (AMI) remains one of the leading causes of death in the developed world. There is emerging evidence that the cytokine macrophage migration inhibitory factor (MIF) is a crucial player in AMI. Cardioprotection by MIF is likely to be a multifactorial phenomenon mediated by receptor-mediated signalling processes, intracellular protein-protein interactions, and enzymatic redox regulation. Co-ordinating several pathways in the ischaemic heart, MIF contributes to receptor-mediated regulation of cardioprotective AMP-activated protein kinase signalling, inhibition of pro-apoptotic cascades, and the reduction of oxidative stress in the post-ischaemic heart. Moreover, the cardioprotective properties of MIF are modulated by S-nitros(yl)ation. These effects in the pathophysiology of myocardial ischaemia/reperfusion injury qualify MIF as a promising therapeutic target in the future. We here summarize the findings of experimental and clinical studies and emphasize the therapeutic potential of MIF in AMI.

Assessment of macrophage migration inhibitory factor in humans: protocol for accurate and reproducible levels

The analytical validation of a possible biomarker is the first step in the long translational process from basic science to clinical routine. Although the chemokine-like cytokine macrophage migration inhibitory factor (MIF) has been investigated intensively in experimental approaches to various disease conditions, its transition into clinical research is just at the very beginning. Because of its presence in preformed storage pools, MIF is the first cytokine to be released under various stimulation conditions. In the first proof-of-concept studies, MIF levels correlated with the severity and outcome of various disease states. In a recent small study with acute coronary syndrome patients, elevation of MIF was described as a new factor for risk assessment. When these studies are compared, not only MIF levels in diseased patients differ, but also MIF levels in healthy control groups are inconsistent. Blood MIF concentrations in control groups vary between 0.56 and 95.6 ng/ml, corresponding to a 170-fold difference. MIF concentrations in blood were analyzed by ELISA. Other than the influence of this approach due to method-based variations, the impact of preanalytical processing on MIF concentrations is unclear and has not been systematically studied yet. Before large randomized studies are performed to determine the impact of circulating MIF on prognosis and outcome and before MIF is characterized as a diagnostic marker, an accurate protocol for the determination of reproducible MIF levels needs to be validated. In this study, the measurement of MIF in the blood of healthy volunteers was investigated focusing on the potential influence of critical preanalytical factors such as anticoagulants, storage conditions, freeze/thaw stability, hemolysis, and dilution. We show how to avoid pitfalls in the measurement of MIF and that MIF concentrations are highly susceptible to preanalytical factors. MIF serum concentrations are higher than plasma concentrations and show broader ranges. MIF concentrations are higher in samples processed with latency than in those processed directly and strongly correlate with hemoglobin in plasma. Neither storage temperature nor storage length or dilution or repeated freezing and thawing influenced MIF concentrations in plasma. Preanalytical validation of MIF is essential. In summary, we suggest using plasma and not serum samples when determining circulating MIF and avoiding hemolysis by processing samples immediately after blood drawing.

The Systematic COronary Risk Evaluation (SCORE) in a large UK population: 10-year follow-up in the EPIC-Norfolk prospective population study

BACKGROUND

The European Society of Cardiology endorses cardiovascular disease (CVD) risk stratification using the Systematic COronary Risk Evaluation (SCORE) algorithm, with separate algorithms for high-risk and low-risk countries. In the 2012 European Guidelines on CVD Prevention in Clinical Practice, the UK has been reclassified as a low-risk country. However, the performance of the SCORE algorithm has not been validated in the UK.

DESIGN

We compared CVD mortality as predicted by SCORE with the observed CVD mortality in the European Prospective Investigation of Cancer-Norfolk (EPIC-Norfolk) prospective population study, a cohort representative of the general population.

METHODS

Individuals without known CVD or diabetes mellitus, aged 39-65 years at baseline, were included in our analysis. CVD mortality was defined as death due to ischaemic heart disease, cardiac failure, cerebrovascular disease, peripheral artery disease and aortic aneurysm. Predicted CVD mortality was calculated at baseline using the SCORE high-risk and low-risk algorithms.

RESULTS

A total of 15,171 individuals (57.1% female) with a mean age of 53.9 (SD 6.2) years were included. Predicted CVD mortality was 2.85% (95% confidence interval (CI) 2.80-2.90) with the SCORE high-risk algorithm and 1.55% (95% CI 1.52-1.58) with the low-risk algorithm. The observed 10-year CVD mortality was 1.25% (95% CI 1.08-1.44). Similar results were observed across sex and age subgroups.

CONCLUSION

In the large EPIC-Norfolk cohort representative of the UK population, the SCORE low-risk algorithm performed better than the high-risk algorithm in predicting 10-year CVD mortality. Our findings indicate that the UK has been correctly reclassified as a low-risk country.

Inflammatory biomarkers for predicting cardiovascular disease

The pathology of cardiovascular disease (CVD) is complex; multiple biological pathways have been implicated, including, but not limited to, inflammation and oxidative stress. Biomarkers of inflammation and oxidative stress may serve to help identify patients at risk for CVD, to monitor the efficacy of treatments, and to develop new pharmacological tools. However, due to the complexities of CVD pathogenesis there is no single biomarker available to estimate absolute risk of future cardiovascular events. Furthermore, not all biomarkers are equal; the functions of many biomarkers overlap, some offer better prognostic information than others, and some are better suited to identify/predict the pathogenesis of particular cardiovascular events. The identification of the most appropriate set of biomarkers can provide a detailed picture of the specific nature of the cardiovascular event. The following review provides an overview of existing and emerging inflammatory biomarkers, pro-inflammatory cytokines, anti-inflammatory cytokines, chemokines, oxidative stress biomarkers, and antioxidant biomarkers. The functions of each biomarker are discussed, and prognostic data are provided where available.

Self-rated health and cardiovascular disease incidence: results from a longitudinal population-based cohort in Norfolk, UK

INTRODUCTION

Self-rated health (SRH) predicts chronic disease morbidity including cardiovascular disease (CVD). In a population-based cohort, we examined the association between SRH and incident CVD and whether this association was independent of socio-demographic, clinical and behavioural participant characteristics.

METHODS

Population-based prospective cohort study (European Prospective Investigation of Cancer-Norfolk). 20,941 men and women aged 39-74 years without prevalent CVD attended a baseline health examination (1993-1998) and were followed for CVD events/death until March 2007 (mean 11 years). We used a Cox proportional hazards model to quantify the association between baseline SRH (reported on a four point scale--excellent, good, fair, poor) and risk of developing CVD at follow-up after adjusting for socio-demographic, clinical and behavioural risk factors.

RESULTS

Baseline SRH was reported as excellent by 17.8% participants, good by 65.1%, fair by 16.0% and poor by 1.2%. During 225,508 person-years of follow-up, there were 55 (21.2%) CVD events in the poor SRH group and 259 (7.0%) in the excellent SRH group (HR 3.7, 95% CI 2.8-4.9). The HR remained significant after adjustment for behavioural risk factors (HR 2.6, 95% CI 1.9-3.5) and after adjustment for all socio-demographic, clinical and behavioural risk factors (HR 3.3, 95% CI 2.4-4.4). Associations were strong for both fatal and non-fatal events and remained strong over time.

CONCLUSIONS

SRH is a strong predictor of incident fatal and non-fatal CVD events in this healthy, middle-aged population. Some of the association is explained by lifestyle behaviours, but SRH remains a strong predictor after adjustment for socio-demographic, clinical and behavioural risk factors and after a decade of follow-up. This easily accessible patient-centred measure of health status may be a useful indicator of individual and population health for those working in primary care and public health.

Proinflammatory cytokines, adiponectin, and increased risk of primary cardiovascular events in diabetic patients with or without renal dysfunction: results from the ESTHER study

OBJECTIVE

Inflammatory processes contribute to both diabetes and cardiovascular risk. We wanted to investigate whether circulating concentrations of proinflammatory immune mediators and adiponectin in diabetic patients are associated with incident cardiovascular events.

RESEARCH DESIGN AND METHODS

In 1,038 participants with diabetes of the population-based ESTHER study, of whom 326 showed signs of renal dysfunction, Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs for the association of increasing concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), IL-18, macrophage migration inhibitory factor (MIF), adiponectin, and leptin with cardiovascular events (myocardial infarction, stroke, or fatal cardiovascular event) during a follow-up period of 8 years.

RESULTS

During follow-up, 161 subjects with diabetes experienced a primary cardiovascular event. Proinflammatory markers were not associated with a higher risk for primary cardiovascular events in the total study population after adjustment for multiple confounders. However, IL-6 and MIF were associated with cardiovascular events in subjects with renal dysfunction (HR for the comparison of top vs. bottom tertile 1.98 [95% CI 1.12-3.52], P [trend] = 0.10 for IL-6; 1.48 [0.87-2.51], P [trend] = 0.04 for MIF). Adiponectin levels were associated with cardiovascular events in the total population (1.48 [1.01-2.21], P [trend] = 0.03), and the association was even more pronounced in the subgroup with renal dysfunction (1.97 [1.08-3.57], P [trend] = 0.02).

CONCLUSIONS

In particular, the absence of an association between CRP and a U-shaped association of adiponectin levels with incident cardiovascular events show that associations between circulating immune mediators and cardiovascular risk differ between diabetic patients and subjects of the general population.

Change in HbA1c over 3 years does not improve the prediction of cardiovascular disease over and above HbA1c measured at a single time point

AIMS/HYPOTHESIS

HbA1c is an important risk factor for cardiovascular disease (CVD), with 1% higher HbA1c levels associated with a 10-20% increased risk of CVD. Little is known about the association between change in HbA1c over time and cardiovascular risk in non-diabetic populations. This study examined the association between change in HbA1c over time and cardiovascular risk in a non-diabetic British population.

METHODS

We used data on HbA1c collected at baseline and at a second health examination 3 years later among a population of 5,790 non-diabetic men and women who participated in the European Prospective Investigation of Cancer (EPIC)-Norfolk. The association between change in HbA1c over 3 years and incident cardiovascular events over the following 8 years was examined using multivariate Cox regression. We also examined whether information on change in HbA1c over time improved prediction of cardiovascular events over a single measure of HbA1c by comparing the area under the receiver operating characteristic curves (aROC) and computing the net reclassification improvement.

RESULTS

The mean change (SD) in HbA1c over 3 years was 0.13% (0.52). During 44,596 person-years of follow-up, 529 cardiovascular events occurred (incidence 11.9 per 1,000 person-years). Each 0.5% rise in HbA1c over 3 years was associated with a 9% increase in risk of a cardiovascular event (HR 1.09; 95% CI 1.01, 1.18) after adjustment for baseline HbA1c and other major cardiovascular risk factors. However, change in HbA1c was not associated with cardiovascular risk after adjustment for HbA1c at follow-up. Multivariate models with and without information on change in HbA1c over time showed a similar aROC of 0.78. Adding change in HbA1c to the model with HbA1c at follow-up did not improve risk classification.

CONCLUSIONS/INTERPRETATION

Addition of information on change in HbA1c over 3 years did not improve the prediction of CVD over and above information on HbA1c and other major cardiovascular risk factors from a single time point.

Vascular disease in women: comparison of diagnoses in hospital episode statistics and general practice records in England

Background

Electronic linkage to routine administrative datasets, such as the Hospital Episode Statistics (HES) in England, is increasingly used in medical research. Relatively little is known about the reliability of HES diagnostic information for epidemiological studies. In the United Kingdom (UK), general practitioners hold comprehensive records for individuals relating to their primary, secondary and tertiary care. For a random sample of participants in a large UK cohort, we compared vascular disease diagnoses in HES and general practice records to assess agreement between the two sources.

Methods

Million Women Study participants with a HES record of hospital admission with vascular disease (ischaemic heart disease [ICD-10 codes I20-I25], cerebrovascular disease [G45, I60-I69] or venous thromboembolism [I26, I80-I82]) between April 1^st 1997 and March 31^st 2005 were identified. In each broad diagnostic group and in women with no such HES diagnoses, a random sample of about a thousand women was selected for study. We asked each woman’s general practitioner to provide information on her history of vascular disease and this information was compared with the HES diagnosis record.

Results

Over 90% of study forms sent to general practitioners were returned and 88% of these contained analysable data. For the vast majority of study participants for whom information was available, diagnostic information from general practice and HES records was consistent. Overall, for 93% of women with a HES diagnosis of vascular disease, general practice records agreed with the HES diagnosis; and for 97% of women with no HES diagnosis of vascular disease, the general practitioner had no record of a diagnosis of vascular disease. For severe vascular disease, including myocardial infarction (I21-22), stroke, both overall (I60-64) and by subtype, and pulmonary embolism (I26), HES records appeared to be both reliable and complete.

Conclusion

Hospital admission data in England provide diagnostic information for vascular disease of sufficient reliability for epidemiological analyses.

High postoperative blood levels of macrophage migration inhibitory factor are associated with less organ dysfunction in patients after cardiac surgery

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine that exerts protective effects during myocardial ischemia/reperfusion injury. We hypothesized that elevated MIF levels in the early postoperative time course might be inversely associated with postoperative organ dysfunction as assessed by the simplified acute physiology score (SAPS) II and sequential organ failure assessment (SOFA) score in patients after cardiac surgery. A total of 52 cardiac surgical patients (mean age [± SD] 67 ± 10 years; EuroScore: 7) were enrolled in this monocenter, prospective observational study. Serum levels of MIF and clinical data were obtained after induction of anesthesia, at admission to the intensive care unit (ICU), 4 h after admission and at the first and second postoperative day. To characterize the magnitude of MIF release, we compared blood levels of samples from cardiac surgical patients with those obtained from healthy volunteers. We assessed patient outcomes using the SAPS II at postoperative d 1 and SOFA score for the first 3 d of the eventual ICU stay. Compared to healthy volunteers, patients had already exhibited elevated MIF levels prior to surgery (64 ± 50 versus 13 ± 17 ng/mL; p < 0.05). At admission to the ICU, MIF levels reached peak values (107 ± 95 ng/mL; p < 0.01 versus baseline) that decreased throughout the observation period and had already reached preoperative values 4 h later. Postoperative MIF values were inversely correlated with SAPS II and SOFA scores during the early postoperative stay. Moreover, MIF values on postoperative d 1 were related to the calculated cardiac power index (r = 0.420, p < 0.05). Elevated postoperative MIF levels are inversely correlated with organ dysfunction in patients after cardiac surgery.

A comparative analysis of three widely used lipid management guidelines in the EPIC-Norfolk cohort

AIMS

To compare the impact of three major guidelines for the prevention of cardiovascular disease (CVD).

METHODS AND RESULTS

21,263 men and women aged 39-79 years from the EPIC (European Prospective Investigation of Cancer) Norfolk cohort were retrospectively classified at baseline by statin therapy recommendations according to the NICE, ESC and ATPIII CVD prevention guidelines. Recommendations based on baseline data were related to 10-year follow-up to calculate number of new CVD events that could be prevented by statins, number-needed-to-treat (NNT) and CVD incidence decrease. Statin therapy was recommended to 34% by the NICE guideline, 29% by ESC and 32% by ATPIII. A total of 263 events could potentially have been prevented by application of the NICE guideline, 219 by ESC and 199 by ATPIII. The NNT with statins over 10 years was 27 with the NICE guideline, 28 with ESC and 34 with ATPIII. Application of the NICE guideline could have decreased CVD incidence by 13%; using ESC guidelines the figure is 11% and with ATPIII it is 10%.

CONCLUSIONS

The NICE guideline selected greater percentages of elderly and subjects with prevalent CVD risk factors. It performed best in recommending statins and could have prevented the greatest number of CVD events. With all guidelines, nearly half the subjects who developed a CVD event were not considered eligible for statins at baseline. Less selective prevention strategies need to be explored.

Individual and cumulative effect of type 2 diabetes genetic susceptibility variants on risk of coronary heart disease

AIMS/HYPOTHESIS

Type 2 diabetes is a major risk factor for CHD. We hypothesised that diabetes genetic susceptibility variants might be associated with increased CHD risk.

METHODS

We examined the individual and cumulative effect of 38 common genetic variants previously reported to be associated with type 2 diabetes on risk of incident CHD in 20,467 participants of the European Prospective Investigation into Cancer and Nutrition (EPIC) Norfolk Study who had been free of CHD at baseline.

RESULTS

During a mean follow-up of 10.7 years, 2,190 participants had a CHD event. Two individual variants next to the TSPAN8 (HR 1.07, 95% CI 1.00-1.14) and the CDKN2A/B region (1.11, 1.04-1.17) were significantly associated with increased CHD risk. A genetic score based on the 38 diabetes variants was significantly associated with an increased risk of CHD (1.08, 1.01-1.14 per score tertile). Adjustment for prevalent and incident diabetes attenuated the association of the TSPAN8 variant (1.06, 0.99-1.13) and the genetic score (1.05, 0.99-1.12 per score tertile) with CHD risk, but not that of the CDKN2A/B variant (1.11, 1.05-1.18). Addition of the genetic score did not improve risk discrimination based on clinical risk factors.

CONCLUSIONS/INTERPRETATION

The increased risk of CHD observed with genetic susceptibility to type 2 diabetes was at least partly mediated by its diabetes-predisposing effect and was not useful for clinical risk discrimination. The potential role of pathways associated with the variant CDKN2A/B in linking diabetes and CHD needs further exploration.

Prolactin and autoimmunity

The relationship between prolactin and the immune system has been demonstrated in the last two decades, opening new windows in the field of the immunoendocrinology. Prolactin has an important role in the innate and adaptive immune response. Increased prolactin levels have been described in autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, Sjögren syndrome, and systemic sclerosis among others. Hyperprolactinemia is associated with active disease and organ involvement in systemic lupus erythematosus. Therefore, prolactin is an integral member of the immunoneuroendocrinology network and seems to have a role in pathogenesis of autoimmune diseases. Few controlled studies of dopamine agonist treatment in humans with autoimmune disease have been conducted only in systemic lupus erythematosus patients, which support the potential efficacy of such agents even during pregnancy and postpartum. Further studies are necessary to elucidate the mechanisms by which prolactin affects autoimmune disease activity, increase the inflammatory mechanism, and determine the role of anti-prolactinemic drugs to regulate the immune/inflammatory process.

Non-diabetic hyperglycaemia and cardiovascular risk: moving beyond categorisation to individual interpretation of absolute risk

AIMS/HYPOTHESIS

Non-diabetic hyperglycaemia is usually not considered at all or is viewed as a binary risk category in isolation from other factors when quantifying cardiovascular risk. We argue that hyperglycaemia should be considered as a continuous risk factor and only in the context of other vascular risk factors. To examine the potential impact of hyperglycaemia on cardiovascular disease (CVD) risk, we calculated the absolute CVD risk in groups defined by different levels of HbA(1c) and other CVD risk factors.

METHODS

We used data on 10,144 men and women from the European Prospective Investigation of Cancer-Norfolk cohort to calculate CVD rates across levels of HbA(1c) in groups characterised by different levels of traditional risk factors.

RESULTS

We found significant differences in CVD rates across levels of HbA(1c) in groups defined by different levels of the other risk factors. CVD rates for non-diabetic individuals with an HbA(1c) of <5.5% increased from 0.6 (95% CI 0.3-1.2) to 29.6 (95% CI 14.8-59.1) per 1,000 person-years when traditional CVD risk factors were added sequentially to the lowest risk reference group. In most cases, non-diabetic individuals with an HbA(1c) of <5.5% and high values for all other CVD risk factors had substantially higher absolute CVD rates than those with an HbA(1c) of 6.0% to 6.4% but with no other raised CVD risk factors (29.6 [95% CI 14.8-59.1] and 2.5 [95% CI 0.4-18.1], respectively). A history of diabetes significantly increased CVD risk over the non-diabetic hyperglycaemia range. Comparisons of CVD rates across tertiles of total cholesterol:HDL-cholesterol ratio or mean systolic blood pressure in groups characterised by different levels of other risk factors showed similar findings.

CONCLUSIONS/INTERPRETATION

In people with non-diabetic hyperglycaemia, cardiovascular risk is highly dependent on the presence of other CVD risk factors. Attention should be given not to whether an individual has 'pre-diabetes', 'hypertension' or 'hypercholesterolaemia', but to an integrated assessment of CVD risk, based on the combination of risk factors present and potential benefits of treatment.

A simple risk score using routine data for predicting cardiovascular disease in primary care

BACKGROUND

Population-based screening for cardiovascular disease (CVD) risk, incorporating blood tests, is proposed in several countries.

AIM

The aim of this study was to evaluate whether a simple approach to identifying individuals at high risk of CVD using routine data might be effective.

DESIGN OF STUDY

Prospective cohort study (EPIC-Norfolk).

SETTING

Norfolk area, UK.

METHOD

A total of 21 867 men and women aged 40-74 years, who were free from CVD and diabetes at baseline, participated in the study. The discrimination (the area under the receiver operating characteristic curve [aROC]), calibration, sensitivity/specificity, and positive/negative predictive value were evaluated for different risk thresholds of the Framingham risk equations and the Cambridge diabetes risk score (as an example of a simple risk score using routine data from electronic general practice records).

RESULTS

During 203 664 person-years of follow-up, 2213 participants developed a first CVD event (10.9 per 1000 person-years). The Cambridge diabetes risk score predicted CVD events reasonably well (aROC 0.72; 95% confidence interval [CI] = 0.71 to 0.73), while the Framingham risk score had the best predictive ability (aROC 0.77; 95% CI = 0.76 to 0.78). The Framingham risk score overestimated risk of developing CVD in this representative British population by 60%.

CONCLUSION

A risk score incorporating routinely available data from GP records performed reasonably well at predicting CVD events. This suggests that it might be more efficient to use routine data as the first stage in a stepwise population screening programme to identify people at high risk of developing CVD before more time- and resource-consuming tests are used.

Family history of premature coronary heart disease and risk prediction in the EPIC-Norfolk prospective population study

OBJECTIVE

The value of a family history for coronary heart disease (CHD) in addition to established cardiovascular risk factors in predicting an individual's risk of CHD is unclear. In the European Prospective Investigation of Cancer (EPIC)-Norfolk cohort, the authors tested whether adding family history of premature CHD in first-degree relatives improves risk prediction compared with the Framingham risk score (FRS) alone.

METHODS AND RESULTS

This study comprised 10,288 men and 12,553 women aged 40-79 years participating in the EPIC-Norfolk cohort who were followed for a mean of 10.9±2.1 years (mean±SD). The authors computed the FRS as well as a modified score taking into account family history of premature CHD. A family history of CHD was indeed associated with an increased risk of future CHD, independent of established risk factors (FRS-adjusted HR of 1.74 (95% CI 1.56 to 1.95) for family history of premature CHD). However, adding family history of CHD to the FRS resulted in a negative net reclassification of 2%. In the subgroup of individuals estimated to be at intermediate risk, family history of premature CHD resulted in an increase in net reclassification of 2%. The sensitivity increased with 0.4%, and the specificity decreased 0.8%.

CONCLUSION

Although family history of CHD was an independent risk factor of future CHD, its use did not improve classification of individuals into clinically relevant risk categories based on the FRS. Among study participants at intermediate risk of CHD, adding family history of premature CHD resulted in, at best, a modest improvement in reclassification of individuals into a more accurate risk category.

The hypertriglyceridemic-waist phenotype and the risk of coronary artery disease: results from the EPIC-Norfolk prospective population study

BACKGROUND

Screening for increased waist circumference and hypertriglyceridemia (the hypertriglyceridemic-waist phenotype) has been proposed as an inexpensive approach to identify patients with excess intra-abdominal adiposity and associated metabolic abnormalities. We examined the relationship between the hypertriglyceridemic-waist phenotype to the risk of coronary artery disease in apparently healthy individuals.

METHODS

A total of 21,787 participants aged 45-79 years were followed for a mean of 9.8 (standard deviation 1.7) years. Coronary artery disease developed in 2109 of them during follow-up. The hypertriglyceridemic-waist phenotype was defined as a waist circumference of 90 cm or more and a triglyceride level of 2.0 mmol/L or more in men, and a waist circumference of 85 cm or more and a triglyceride level of 1.5 mmol/L or more in women.

RESULTS

Compared with participants who had a waist circumference and triglyceride level below the threshold, those with the hypertriglyceridemic-waist phenotype had higher blood pressure indices, higher levels of apolipoprotein B and C-reactive protein, lower levels of high-density lipoprotein cholesterol and apolipoprotein A-I, and smaller low-density lipoprotein particles. Among men, those with the hypertriglyceridemic-waist phenotype had an unadjusted hazard ratio for future coronary artery disease of 2.40 (95% confidence interval [CI] 2.02-2.87) compared with men who did not have the phenotype. Women with the phenotype had an unadjusted hazard ratio of 3.84 (95% CI 3.20-4.62) compared with women who did not have the phenotype.

INTERPRETATION

Among participants from a European cohort representative of a contemporary Western population, the hypertriglyceridemic-waist phenotype was associated with a deteriorated cardiometabolic risk profile and an increased risk for coronary artery disease.

Chemokine ligand 2 genetic variants, serum monocyte chemoattractant protein-1 levels, and the risk of coronary artery disease

OBJECTIVE

In humans, evidence about the association between levels of monocyte chemoattractant protein-1 (MCP-1), its coding gene chemokine (C-C motif) ligand 2 (CCL2), and risk of coronary artery disease (CAD) is contradictory.

METHODS AND RESULTS

We performed a nested case-control study in the prospective EPIC-Norfolk cohort investigating the relationship between CCL2 single-nucleotide polymorphisms (SNPs), MCP-1 concentrations, and the risk of future CAD. Cases (n=1138) were apparently healthy men and women aged 45 to 79 years who developed fatal or nonfatal CAD during a mean follow-up of 6 years. Controls (n=2237) were matched by age, sex, and enrollment time. Using linear regression analysis no association between CCL2 SNPs and MCP-1 serum concentrations became apparent, nor did we find a significant association between MCP-1 serum levels and risk of future CAD. Finally, Cox regression analysis showed no significant association between CCL2 SNPs and the future CAD risk. In addition, we did not find any robust associations between the CCL2 haplotypes and MCP-1 serum concentration or future CAD risk.

CONCLUSIONS

Our data do not support previous publications indicating that MCP-1 is involved in the pathogenesis of CAD.

Estimating the population impact of screening strategies for identifying and treating people at high risk of cardiovascular disease: modelling study

OBJECTIVE

To estimate the potential population impact of different screening strategies for identifying and treating people at high risk of cardiovascular disease, including strategies using routine data for cardiovascular risk stratification, in light of the UK government's recommended national strategy to screen all adults aged 40-74 for cardiovascular risk.

DESIGN

Modelling study using data from a prospective cohort, EPIC-Norfolk (European Prospective Investigation of Cancer-Norfolk).

SETTING

An English county.

PARTICIPANTS

16,970 men and women aged 40-74 and free from cardiovascular disease and diabetes at baseline.

MAIN OUTCOME MEASURES

The main outcomes were the population attributable fraction, the number needed to screen to prevent one new case of cardiovascular disease, the number needed to treat to prevent one new case of cardiovascular disease, and the number of new cardiovascular events that could be prevented. Relative risk reductions for estimated treatment effects were derived from meta-analyses of clinical trials or guidelines from the National Institute for Health and Clinical Excellence.

RESULTS

1362 cardiovascular events occurred over 183 586 person years of follow-up. Compared with the recommended government strategy, a stepwise screening approach using a simple risk score incorporating routine data could prevent a similar number (lower to upper estimates) of new cardiovascular events annually in the United Kingdom (26,789, 20,778 to 36,239) and 25,134 (19,450 to 34,134), respectively) but requiring only 60% of the population to be invited to attend a vascular risk assessment. A similar number of cardiovascular events (25,016, 19,563 to 33,372) could also be prevented by inviting everyone aged 50-74 for a vascular assessment. Using a participant completed Finnish diabetes risk score questionnaire or anthropometric cut-off points for risk prestratification was less effective.

CONCLUSIONS

Compared with the UK government's recommended national strategy to screen all adults aged 40-74 for cardiovascular risk, an approach using routine data for cardiovascular risk stratification before inviting people at high risk for a vascular risk assessment may be similarly effective at preventing new cases of cardiovascular disease, with potential cost savings.

Initial thyroid status and cardiovascular risk factors: the EPIC-Norfolk prospective population study

CONTEXT

Thyroid status affects several aspects of cardiovascular risk profile, including lipid levels and blood pressure. Whether thyroid status affects the risk of coronary heart disease (CHD) and all-cause mortality remains controversial.

DESIGN

The EPIC-Norfolk prospective population study. Mean follow-up was 10.6 years.

PATIENTS

Study participants were 11 554 men and women aged 45-79 years, who were living in Norfolk, UK.

MEASUREMENTS

Baseline cardiovascular risk factors were recorded and concentrations of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were measured in baseline samples. Regression analyses were performed to assess the association between thyroid hormone levels and cardiovascular risk factors. A proportional hazards model was used to estimate the risk of CHD and all-cause mortality by baseline thyroid status. No information was available on thyroid treatment during follow-up.

RESULTS

Thyroid abnormalities were common, particularly among women. Thyroid abnormalities were associated with an altered cardiovascular risk profile. Even within the normal range, thyroid hormone levels, TSH more strongly than FT4, were associated with lipid levels and blood pressure among both men and women. We did not observe a significant association between subclinical thyroid abnormalities and risk of CHD or all-cause mortality.

CONCLUSIONS

Despite the association between thyroid hormone levels and cardiovascular risk factors, thyroid status was not statistically significantly associated with the risk of future CHD or all-cause mortality in this large cohort.