Inflammatory markers and extent and progression of early atherosclerosis: Meta-analysis of individual-participant-data from 20 prospective studies of the PROG-IMT collaboration

Recent advances in understanding autoimmune thyroid disease: the tallest tree in the forest of polyautoimmunity

Autoimmune thyroid disease (AITD) is often observed together with other autoimmune diseases. The coexistence of two or more autoimmune diseases in the same patient is referred to as polyautoimmunity, and AITD is the autoimmune disease most frequently involved. The occurrence of polyautoimmunity has led to the hypothesis that the affected patients suffer from a generalized dysregulation of their immune system. The present review summarizes recent discoveries unravelling the immunological mechanisms involved in autoimmunity, ranging from natural autoimmunity to disease-specific autoimmunity. Furthermore, the clinical grounds for considering AITD in a setting of polyautoimmunity are explored. A better understanding of these may pave the way for designing new treatment modalities targeting the underlying immune dysregulation when AITD appears in the context of polyautoimmunity.

[Stenosis of the carotid artery in women with ischemic stroke and markers of inflammation]

AIM

To assess the relationship between the severity of stenosis of the carotid arteries, the level of female sex hormones and markers of subclinical inflammation in women with ischemic stroke (IS).

MATERIAL AND METHODS

Two hundred and eleven women (mean age 68.9±9.23 years) were examined. A history of cardiovascular disease, previous cardiovascular events, type and subtype of stroke were recorded. Neurological status was assessed using neurological scales. Atherosclerosis was diagnosed by color duplex scanning of brachiocephalic arteries and laboratory testing (estradiol, markers of subclinical inflammation).

RESULTS

Carotid artery stenosis of ≥50% was found in 13.3% of patients, less severe stenosis in 36.0%. Stenosis of ≥50% was positively correlated with the level of IL-18, TNF-alpha, and negatively correlated with the level of IL-6, IL-4, and MMSE score. In dynamics, there was a decrease in the level of TNF-alpha in all groups of patients, and an increase in the IL-4 level in women with carotid artery stenosis of ≥50%.

CONCLUSION

Study of the influence of markers of subclinical inflammation on the atherosclerosis progression and recurrent disorders of cerebral circulation in women with IS should be continued.

C-reactive protein in atherosclerosis - A risk marker but not a causal factor? A 13-year population-based longitudinal study: The Tromsø study

BACKGROUND AND AIMS

CRP predicts cardiovascular disease (CVD) in large epidemiologic studies. The aim of the present study was to elucidate the role of CRP in atherosclerosis formation and progression in a prospective population-based study.

METHODS

6503 middle-aged subjects from The Tromsø study had serum CRP, carotid ultrasound and complete covariate data collected at baseline in 1994. Of these, 4730 and 2917 attended follow-up surveys with repeated assessments in 2001 and 2007, respectively. The cross-sectional associations between CRP and subclinical carotid atherosclerosis, and the longitudinal associations between baseline CRP and novel plaque formation and plaque progression were assessed in generalized estimating equations and linear mixed models stratified by sex.

RESULTS

At baseline, traditional risk factors and plaque prevalence increased by CRP risk categories (<1 mg/L, 1-3 mg/L, and >3 mg/L) in both sexes. In cross-sectional analyses, multivariable-adjusted CRP was associated with plaque prevalence and total plaque area (TPA) in men and women. Age-adjusted baseline CRP >3 mg/L compared to CRP <1 mg/L predicted novel plaque formation (OR 1.44, CI 1.08-1.92) and TPA progression (β = 0.0.029 (CI, 0.003-0.056)) in men, but not in women. In neither men nor women was baseline CRP a predictor of TPA-progression or novel plaque formation when adjusted for traditional risk factors.

CONCLUSIONS

CRP was associated with plaque presence and TPA in cross-sectional analyses, but was not an independent predictor of novel plaque formation or plaque progression. Our findings suggest that CRP may link to CVD by other mechanisms than promoting formation and progression of atherosclerotic plaques.

Impact of Venous Thromboembolism on the Formation and Progression of Carotid Atherosclerosis: The Tromsø Study

Venous thromboembolism (VTE) is associated with increased risk of arterial cardiovascular diseases (CVD), and development of atherosclerosis secondary to VTE may be an intermediate between VTE and CVD. Therefore, we aimed to investigate whether incident VTE was associated with subsequent carotid atherosclerosis formation and progression in a population-based observational study. Subjects attending two or more ultrasound examinations of the right carotid artery, with measurement of total plaque area (TPA), in the Tromsø Study in 1994–1995, 2001–2002, and/or 2007–2008 were eligible. We identified 150 subjects diagnosed with first-lifetime VTE between the initial and follow-up visit, and randomly selected 600 age- and sex-matched subjects without VTE between the visits. Subjects with VTE and carotid plaque(s) at the first visit had 4.1 mm ² (β: 4.13, 95% CI: −1.72 to 9.98) larger change in TPA between the first and second visit compared with subjects without VTE after adjustment for change in high-sensitivity C-reactive protein (hs-CRP) and traditional atherosclerotic risk factors. The association remained after restricting the analyses to VTE events diagnosed in the first half of the time interval between the carotid ultrasounds (β: 4.02, 95% CI: −3.66 to 11.70), supporting that the change in TPA occurred subsequent to the VTE. No association was found between VTE and novel carotid plaque formation. In conclusion, we found a possible association between VTE and atherosclerosis progression in those with already established carotid plaques, but not between VTE and novel plaque formation. The association between VTE and carotid plaque progression was not mediated by low-grade inflammation assessed by hs-CRP.

Serum fibrinogen and cardiovascular events in Chinese patients with type 2 diabetes and stable coronary artery disease: a prospective observational study

OBJECTIVES

The aim of this study was to investigate the association of serum fibrinogen with cardiovascular events (CVE) in Chinese patients with type 2 diabetes mellitus (T2DM) and stable coronary artery disease (CAD).

DESIGN

An observational study.

SETTING

FuWai Hospital in Beijing, China.

PARTICIPANTS

A cohort of 1466 patients with T2DM and angiographic-proven stable CAD was evaluated.

OUTCOME MEASURES

Baseline serum fibrinogen levels were measured and trisected into 'low', 'middle' and 'high'. Their association with CVE was explored using Cox proportional hazard models.

RESULTS

With 20.2 months (average) follow-up, 44 (3%) were lost to follow-up and 96 patients developed CVE. Compared with the patients without CVE, the ones who developed CVE had higher levels of fibrinogen. Univariable regression revealed a significant relation of fibrinogen to CVE (HR (HR) 1.25, 95% CI 1.06 to 1.47, p=0.010) per SD increase of fibrinogen at baseline. After adjusting for multiple established cardiovascular disease (CVD) risk factors, the association persisted (HR 1.30, 95% CI 1.02 to 1.66, p=0.037). Moreover, after adjusting for CVD risk factors, the HRs for middle-serum and high-serum fibrinogen concentration, using 'low' group as reference, were 1.23 (95% CI 0.69 to 2.20) and 2.20 (95% CI 1.11 to 3.36, p=0.049).

CONCLUSIONS

We first indicated that elevated fibrinogen level was independently associated with increased CVE in Chinese patients with T2DMand stable CAD.

Dietary inflammatory index and risk of first myocardial infarction; a prospective population-based study

BACKGROUND

Chronic, low-grade inflammation is an established risk factor for cardiovascular disease. The inflammatory impact of diet can be reflected by concentrations of inflammatory markers in the bloodstream and the inflammatory potential of diet can be estimated by the dietary inflammatory index (DII^TM), which has been associated with cardiovascular disease risk in some previous studies. We aimed to examine the association between the DII and the risk of first myocardial infarction (MI) in a population-based study with long follow-up.

METHOD

We conducted a prospective case-control study of 1389 verified cases of first MI and 5555 matched controls nested within the population-based cohorts of the Northern Sweden Health and Disease Study (NSHDS), of which the largest is the ongoing Västerbotten Intervention Programme (VIP) with nearly 100 000 participants during the study period. Median follow-up from recruitment to MI diagnosis was 6.4 years (6.2 for men and 7.2 for women). DII scores were derived from a validated food frequency questionnaire (FFQ) administered in 1986-2006. Multivariable conditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI), using quartile 1 (most anti-inflammatory diet) as the reference category. For validation, general linear models were used to estimate the association between the DII scores and two inflammatory markers, high-sensitivity C-reactive protein (hsCRP) and interleukin 6 (IL-6) in a subset (n = 605) of the study population.

RESULTS

Male participants with the most pro-inflammatory DII scores had an increased risk of MI [OR_Q4vsQ1 = 1.57 (95% CI 1.21-2.02) P _trend = 0.02], which was essentially unchanged after adjustment for potential confounders, including cardiovascular risk factors [OR_Q4vsQ1 = 1.50 (95% CI 1.14-1.99), P _trend = 0.10]. No association was found between DII and MI in women. An increase of one DII score unit was associated with 9% higher hsCRP (95% CI 0.03-0.14) and 6% higher IL-6 (95% CI 0.02-0.11) in 605 controls with biomarker data available.

CONCLUSION

A pro-inflammatory diet was associated with an elevated risk of first myocardial infarction in men; whereas for women the relationship was null. Consideration of the inflammatory impact of diet could improve prevention of cardiovascular disease.

Unstable carotid artery plaque: new insights and controversies in diagnostics and treatment

Cardiovascular disease is estimated to be the leading cause of death, globally causing 14 million deaths each year. Stroke remains a massive public health problem and there is an increasing need for better strategies for the prevention and treatment of this disease. At least 20% of ischemic strokes are thromboembolic in nature, caused by a thromboembolism from an atherosclerotic plaque at the carotid bifurcation or the internal carotid artery. Current clinical guidelines for both primary and secondary prevention of stroke in patients with carotid stenosis caused by atherosclerotic plaques remain reliant on general patient characteristics (traditional risk factors for stroke) and static measures of the degree of artery stenosis. Patients with similar traditional risk factors, however, have been found to have different risk of stroke, and it has in recent years become increasingly clear that the degree of artery stenosis alone is not the best estimation of stroke risk. There is a need for new methods for the assessment of stroke risk to improve risk prediction for the individual patient. This review aims to give an overview of new methods available for the identification of carotid plaque instability and the assessment of stroke risk.

Combined Effects of Inflammatory Status and Carotid Atherosclerosis

Background and Purpose—

Inflammatory responses play a key role in atherogenesis. The aim of this study was to assess the prognostic value of hsCRP (high-sensitivity C-reactive protein) and to evaluate whether degree of carotid stenosis and serum levels of hsCRP jointly predict long-term mortality in asymptomatic patients with carotid atherosclerosis.

Methods—

One thousand sixty-five patients with neurological asymptomatic carotid atherosclerosis as evaluated by duplex sonography were prospectively followed for cause-specific mortality.

Results—

During a median of 11.81 years, a total of 549 deaths, including 362 cardiovascular deaths, were recorded. The risk of all-cause and cardiovascular mortality significantly increased in patients with elevated serum levels of hsCRP (the adjusted hazard ratio for cardiovascular mortality per increase of 1 mg/dL of hsCRP levels was 1.47; P <0.001). Patients with a high degree of carotid stenosis and increased hsCRP levels were particularly at risk of adverse outcome. Patients with carotid narrowing over 50% and hsCRP levels >0.29 mg/dL (=median) had nearly twice as high a risk of cardiovascular mortality compared with patients with carotid stenosis of <50% and hsCRP levels <0.29 mg/dL (adjusted hazard ratio 1.89; P <0.001). Improvement in risk stratification with combined assessment of carotid stenosis and hsCRP was confirmed by an improvement of the continuous net reclassification improvement with 18% for all-cause mortality and 15% for cardiovascular mortality compared with the degree of carotid stenosis alone ( P <0.01).

Conclusions—

Measurement of hsCRP in combination with ultrasound investigations of the carotid arteries at a single time point provides additional prognostic information for patients with asymptomatic carotid atherosclerosis.

Serum levels of Lp(a) are related to waist circumference in NAFLD patients with low prevalence of co-morbidities

BACKGROUND

Novel evidence suggests a relationship between circulating Lp(a) levels and the presence of cardiovascular events independently from the cardio-metabolic profile.

METHODS AND RESULTS

The purpose of this study was to investigate serum Lp(a) concentrations in relation to carotid intima-media thickness (IMT), anthropometric measures, lipid profile, assessment of insulin resistance, and other parameters conventionally used to predict CVD risk, in obese patients suffering from hepatic steatosis (HS), the well-known nonalcoholic fatty liver disease (NAFLD). Evidencing the key-points of this research, firstly, serum Lp(a) concentrations were not associated with carotid IMT in this selected population or, consequently, with early atherosclerosis, at least as evaluated by IMT. Secondly, carotid IMT was not predicted by HS severity, as evaluated by ultrasound. Finally, in the adjusted model, Lp(a) was positively predicted by waist circumference (WC) (β = 0.25, t = 2.3, p = 0.02) and negatively by central adiposity, assessed as visceral adipose tissue at US (β = -0.33, t = -3.0, p = 0.003).

CONCLUSION

Serum Lp(a) values may not play a direct role in increasing IMT, albeit associated with WC.

The Role of Dietary Inflammatory Index in Cardiovascular Disease, Metabolic Syndrome and Mortality

Inflammation is an underlying pathophysiological process in chronic diseases, such as obesity, type 2 diabetes mellitus and cardiovascular disease. In fact, a number of systematic reviews have shown the association between inflammatory biomarkers, such as CRP, IL-1β, IL-6, TNF-α, IL-4, or IL-10, and cardio-metabolic diseases. Diet is one of the main lifestyle-related factors which modulates the inflammatory process. Different individual foods and dietary patterns can have a beneficial health effect associated with their anti-inflammatory properties. The dietary inflammatory index (DII) was recently developed to estimate the inflammatory potential of overall diet. The aim of this review is to examine the findings of recent papers that have investigated the association between the DII, cardio-metabolic risk factors and cardiovascular disease. The relevance of the DII score in the association between inflammation and cardio-metabolic diseases is critically appraised, as well as its role in the context of healthy dietary patterns. We conclude that the DII score seems to be a useful tool to appraise the inflammatory capacity of the diet and to better understand the relationships between diet, inflammation, and cardio-metabolic diseases.

White blood cell count may identify abnormal cardiometabolic phenotype and preclinical organ damage in overweight/obese children

BACKGROUND AND AIMS

Subclinical inflammation is a central component of cardiometabolic disease risk in obese subjects. The aim of the study was to evaluate whether the white blood cell count (WBCc) may help to identify an abnormal cardiometabolic phenotype in overweight (Ow) or obese (Ob) children.

METHODS AND RESULTS

A cross-sectional sample of 2835 Ow/Ob children and adolescents (age 6-18 years) was recruited from 10 Italian centers for the care of obesity. Anthropometric and biochemical variables were assessed in the overall sample. Waist to height ratio (WhtR), alanine aminotransferase (ALT), lipids, 2 h post-load plasma glucose (2hPG), left ventricular (LV) geometry and carotid intima-media thickness (cIMT) were assessed in 2128, 2300, 1834, 535 and 315 children, respectively. Insulin resistance and whole body insulin sensitivity index (WBISI) were analyzed using homeostatic model assessment (HOMA-IR) and Matsuda's test. Groups divided in quartiles of WBCc significantly differed for body mass index, WhtR, 2hPG, HOMA-IR, WBISI, lipids, ALT, cIMT, LV mass and relative wall thickness. Children with high WBCc (≥8700 cell/mm(3)) showed a 1.3-2.5 fold increased probability of having high normal 2hPG, high ALT, high cIMT, or LV remodeling/concentric LV hypertrophy, after adjustment for age, gender, pubertal status, BMI and centers.

CONCLUSIONS

This study shows that WBCc is associated with early derangements of glucose metabolism and preclinical signs of liver, vascular and cardiac damage. The WBCc may be an effective and low-cost tool for identifying Ow and Ob children at the greatest risk of potential complications.

Pro-Inflammatory Markers in Relation to Cardiovascular Disease in HIV Infection. A Systematic Review

Background

In the past years many inflammatory markers have been studied in association with clinically manifest cardiovascular disease (CVD) and carotid intima-media thickness (CIMT) in HIV-infected patients, to obtain insights in the increased cardiovascular risk observed in HIV infection. This systematic review provides an oversight of the current knowledge.

Methods

A search was performed in PubMed, Embase and Cochrane in July 2014, identifying all articles from 1996 onwards addressing the relation between inflammatory markers and CVD or CIMT in HIV-positive adults. Two authors, using predefined criteria, independently conducted the selection of articles, critical appraisal and extraction of the data. Analysis was focused on the immune markers that were most frequently assessed. The review protocol was registered in the PROSPERO database at 11 July 2014 (registration number CRD42014010516). This review was performed according to the PRISMA guideline.

Findings

Forty articles were selected; eight addressing cardiovascular disease (CVD) and thirty-two addressing CIMT. C-reactive protein (CRP), interleukin-6 (IL-6) and d-dimer were assessed most frequently in relation to the occurrence of CVD; in four out of eight studies. All three markers were positively related to CVD in three out of four studies. Studies addressing CIMT were too heterogeneous with respect to patient populations, inflammatory markers, CIMT measurement protocols and statistical methods to allow for a formal meta-analysis to obtain summary statistics. CRP, IL-6 and soluble vascular cell adhesion molecule (sVCAM-1) were the most studied markers in relation to CIMT. None of the inflammatory markers showed an association with CIMT.

Interpretation

This review showed a relation between some inflammatory markers and CVD, however, no consistent relation is observed for CIMT. Statistical approaches that yields effect estimates and standardized CIMT protocols should be chosen. Further research should focus on prospective studies and a selected set of inflammatory markers.

Dietary Inflammatory Index and Incidence of Cardiovascular Disease in the SUN Cohort

Background

Diet is known to play a key role in atherogenesis and in the development of cardiovascular events. Dietary factors may mediate these processes acting as potential modulators of inflammation. Potential Links between inflammatory properties of diet and the occurrence of cardiovascular events have not been tested previously.

Objective

We aimed to assess the association between the dietary inflammatory index (DII), a method to assess the inflammatory potential of the diet, and incident cardiovascular disease.

Methods

In the prospective, dynamic SUN cohort, 18,794 middle-aged, Spanish university graduates were followed up for 8.9 years (median). A validated 136-item food-frequency questionnaire was used to calculate the DII. The DII is based on scientific evidence about the relationship between diet and inflammatory biomarkers (C-reactive protein, IL-1β, IL-4, IL-6, IL-10 and TNF-α). Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between the DII and incident cardiovascular disease (myocardial infarction, stroke or cardiovascular death).

Results

The risk for cardiovascular events progressively increased with each increasing quartile of DII (p_trend = 0.017). The multivariable-adjusted HR for participants in the highest (most pro-inflammatory) vs. the lowest quartile of the DII was 2.03 (95% CI 1.06–3.88).

Conclusions

A pro-inflammatory diet was associated with a significantly higher risk for developing cardiovascular events.

Association between red blood cell distribution width (RDW) and carotid artery atherosclerosis (CAS) in patients with primary ischemic stroke

BACKGROUND

The present study aimed to explore the association between RDW and CAS in patients with ischemic stroke, expecting to find a new and significant diagnosis index for clinical practice.

METHODS

This cross-sectional study involves 432 consecutive patients with primary ischemic stroke (within 72 h). All subjects were confirmed by magnetic resonance imaging, and underwent physical examination, laboratory tests and carotid ultrasonography check. Finally, 392 patients were included according to the exclusion criteria. The odds ratios of independent variables were calculated using stepwise multiple logistic regression.

RESULTS

Carotid intimal-medial thickness (IMT) and RDW are both significantly different between CAS group and control group. Univariate analyses show that high-sensitive C-reactive protein (Hs-CRP) and RDW (r=0.436) are both in significantly positive association with IMT. Stepwise multiple logistic regression shows that RDW is an independent protective factor of CAS in patients with ischemic stroke. Compared with the lowest quartile, the second to fourth quartiles are 1.13 (95% CI: 1.13-3.05), 2.02 (95% CI: 1.66-4.67), and 3.10 (95% CI: 2.46-7.65), respectively.

CONCLUSION

The present study suggested that RDW level were higher than non-CAS in patients with primary ischemic stroke. Our results facilitated a bridge to connect RDW with ischemic stroke and further confirmed the role of RDW in the progression of the ischemic stroke.

Markers of inflammation associated with plaque progression and instability in patients with carotid atherosclerosis

Atherosclerosis is the focal expression of a systemic disease affecting medium- and large-sized arteries, in which traditional cardiovascular risk factor and immune factors play a key role. It is well accepted that circulating biomarkers, including C-reactive protein and interleukin-6, reliably predict major cardiovascular events, including myocardial infarction or death. However, the relevance of biomarkers of systemic inflammation to atherosclerosis progression in the carotid artery is less established. The large majority of clinical studies focused on the association between biomarkers and subclinical atherosclerosis, that is, carotid intima-media thickening (cIMT), which represents an earlier stage of the disease. The aim of this work is to review inflammatory biomarkers that were associated with a higher atherosclerotic burden, a faster disease progression, and features of plaque instability, such as inflammation or neovascularization, in patients with carotid atherosclerotic plaque, which represents an advanced stage of disease compared with cIMT. The association of biomarkers with the occurrence of cerebrovascular events, secondary to carotid plaque rupture, will also be presented. Currently, the degree of carotid artery stenosis is used to predict the risk of future cerebrovascular events in patients affected by carotid atherosclerosis. However, this strategy appears suboptimal. The identification of suitable biomarkers could provide a useful adjunctive criterion to ensure better risk stratification and optimize management.