C-reactive protein and cardiovascular disease: a review of risk prediction and interventions

Advancements in electrochemical immunosensors towards point-of-care detection of cardiac biomarkers

Cardiovascular disease remains the leading cause of death worldwide, with mortality rates increasing annually. This underscores the urgent need for accurate diagnostic and monitoring tools. Electrochemical detection has emerged as a promising method for swiftly and precisely measuring specific biomarkers in bodily fluids. This approach is not only cost-effective and efficient compared to traditional clinical methods, but it can also be tailored to detect individual biomarkers, which makes it particularly well-suited for point-of-care (POC) applications. The ability to conduct testing at the point of care is crucial for timely interventions and personalized disease management, empowering healthcare providers to tailor treatment plans based on real-time biomarker data. Thanks to recent advancements in nanomaterials, we've seen significant progress in electrochemical detection, leading to the development of specialized rapid immunoassay systems. These systems utilize specific antibodies to target molecules, expanding the range of detectable biomarkers. This innovation has the potential to revolutionize the diagnosis and treatment of cardiovascular diseases by enhancing detection sensitivity and specificity. Ultimately, these advancements aim to improve patient outcomes by enabling earlier diagnosis, more precise monitoring, and personalized therapeutic interventions, which will contribute to more effective management of cardiovascular health globally.

Sex inequalities in cardiovascular risk prediction

AIMS

Evaluate sex differences in cardiovascular disease (CVD) risk prediction, including use of (i) optimal sex-specific risk predictors and (ii) sex-specific risk thresholds.

METHODS AND RESULTS

Prospective cohort study using UK Biobank, including 121 724 and 182 632 healthy men and women, respectively, aged 38-73 years at baseline. There were 11 899 (men) and 9110 (women) incident CVD cases (hospitalization or mortality) with a median of 12.1 years of follow-up. We used recalibrated pooled cohort equations (PCEs; 7.5% 10-year risk threshold as per US guidelines), QRISK3 (10% 10-year risk threshold as per UK guidelines), and Cox survival models using sparse sex-specific variable sets (via LASSO stability selection) to predict CVD risk separately in men and women. LASSO stability selection included 12 variables in common between men and women, with 3 additional variables selected for men and 1 for women. C-statistics were slightly lower for PCE than QRISK3 and models using stably selected variables, but were similar between men and women: 0.67 (0.66-0.68), 0.70 (0.69-0.71), and 0.71 (0.70-0.72) in men and 0.69 (0.68-0.70), 0.72 (0.71-0.73), and 0.72 (0.71-0.73) in women for PCE, QRISK3, and models using stably selected variables, respectively. At current clinically implemented risk thresholds, test sensitivity was markedly lower in women than men for all models: at 7.5% 10-year risk, sensitivity was 65.1 and 68.2% in men and 24.0 and 33.4% in women for PCE and models using stably selected variables, respectively; at 10% 10-year risk, sensitivity was 53.7 and 52.3% in men and 16.8 and 20.2% in women for QRISK3 and models using stably selected variables, respectively. Specificity was correspondingly higher in women than men. However, the sensitivity in women at 5% 10-year risk threshold increased to 50.1, 58.5, and 55.7% for PCE, QRISK3, and models using stably selected variables, respectively.

CONCLUSION

Use of sparse sex-specific variables improved CVD risk prediction compared with PCE but not QRISK3. At current risk thresholds, PCE and QRISK3 work less well for women than men, but sensitivity was improved in women using a 5% 10-year risk threshold. Use of sex-specific risk thresholds should be considered in any re-evaluation of CVD risk calculators.

Inflammation in acute myocardial infarction: the good, the bad and the ugly

Convergent experimental and clinical evidence have established the pathophysiological importance of pro-inflammatory pathways in coronary artery disease. Notably, the interest in treating inflammation in patients suffering acute myocardial infarction (AMI) is now expanding from its chronic aspects to the acute setting. Few large outcome trials have proven the benefits of anti-inflammatory therapies on cardiovascular outcomes by targeting the residual inflammatory risk (RIR), i.e. the smouldering ember of low-grade inflammation persisting in the late phase after AMI. However, these studies have also taught us about potential risks of anti-inflammatory therapy after AMI, particularly related to impaired host defence. Recently, numerous smaller-scale trials have addressed the concept of targeting a deleterious flare of excessive inflammation in the early phase after AMI. Targeting different pathways and implementing various treatment regimens, those trials have met with varied degrees of success. Promising results have come from those studies intervening early on the interleukin-1 and -6 pathways. Taking lessons from such past research may inform an optimized approach to target post-AMI inflammation, tailored to spare 'The Good' (repair and defence) while treating 'The Bad' (smouldering RIR) and capturing 'The Ugly' (flaming early burst of excess inflammation in the acute phase). Key constituents of such a strategy may read as follows: select patients with large pro-inflammatory burden (i.e. large AMI); initiate treatment early (e.g. ≤12 h post-AMI); implement a precisely targeted anti-inflammatory agent; follow through with a tapering treatment regimen. This approach warrants testing in rigorous clinical trials.

Low-Density Lipoprotein Cholesterol Is Not a Major Determinant of High-Sensitivity C-Reactive Protein Levels in People Without Known Diabetes Mellitus

Background: It has been well established that high-sensitivity C-reactive protein (hs-CRP) is strongly associated with obesity, insulin resistance, high blood pressure, and dyslipidemia. However, the effects of different lipid parameters on hs-CRP levels are less deliberated. The purpose of the study was to compare the relative contribution of triglycerides (TGs), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) to the levels of hs-CRP. Methods: Three hundred seventy-eight subjects without known history of diabetes were recruited for the study. No concomitant antilipid or antidiabetes agents were allowed. Each subject received anthropometric measurements, fasting sampling for lipid profile and hs-CRP, and a 75-gram oral glucose tolerance test for the measurements of insulin resistance (surrogated by insulin sensitivity index ISI0,120). Results: Levels of hs-CRP levels were positively correlated with Log (TG) and negatively correlated with HDL-C in partial correlation after adjustments for confounding variables, but not with LDL-C. The hs-CRP levels in the three groups by tertiles of LDL-C were similar. Subsequently, we found that body mass index (first step), Log (ISI0,120) (second step), and Log (TG) (third step) independently predicted the variance of Log (hs-CRP) in stepwise multiple regression. However, both HDL-C and LDL-C failed to be entered into the models to explain Log (hs-CRP). Conclusions: Our data demonstrated that Log (TG) was a major lipid determinant of hs-CRP levels. The contribution of LDL-C to the levels of hs-CRP might be insignificant.

RANTES (CCL5) in Patients With Geographic Atrophy Age-Related Macular Degeneration

Purpose

A previous study from our research group showed significantly lower levels of RANTES (Regulated upon Activation, Normal T Cell Expressed and Secreted) in patients with intermediate age-related macular degeneration (AMD) compared to control patients with no AMD. The primary aim of this study was to assess levels of RANTES in a cohort of patients with a more advanced form of the disease, geographic atrophy (GA), in comparison with controls.

Methods

The study was conducted on a cohort of patients with GA recruited into a Colorado AMD registry. Cases and controls were defined with multimodal imaging. Plasma levels of the chemokine RANTES were measured using a multiplex assay. A nonparametric (rank-based) regression model was fit to RANTES with a sex by AMD category interaction.

Results

The plasma levels of RANTES were significantly higher in the control group in comparison to the GA AMD group (median [interquartile range]): 10,204 [5799-19,554] pg/mL vs. 5435 [3420-9177] pg/mL, respectively, P < 0.01). When moderated by sex, there was no statistical difference between the male and female GA AMD or the male and female controls.

Conclusions

We found lower level of RANTES in patients with GA AMD compared with controls. This finding is consistent with the findings from our previous intermediate AMD study. However, in contrast to the results of our previous research, when moderated by sex there was no statistical difference between male and female GA patients.

Translational Relevance

The biomarker RANTES is significantly lower in GA AMD patients compared to controls.

Sex differences in cardiovascular risk factor responses to resistance and endurance training in younger subjects

This study compared differences in cardiovascular (CV) risk factor responses between males and females following endurance (END) and resistance (RES) training. We present the frequency of responders to each training modality and the magnitude of response. Using a randomized crossover design, 68 healthy adults [age: female (F): 24.5 ± 4.6; male (M): 27.3 ± 6.6] completed 3 mo of RES and END, with 3 mo washout. Peak oxygen consumption (V̇o_2peak), strength, body composition, blood pressure, glucose, insulin, and lipids were measured. V̇o_2peak (L/min) significantly increased in both sexes following END, but not RES. The magnitude of change was larger in males (F: +0.20 L/min; M: +0.32 L/min), although this did not achieve statistical significance (P = 0.051). Strength significantly increased in both sexes following RES (P < 0.01), with a larger increase in males (Leg press: F: +39 kg; M: +63 kg; P < 0.05). Lean mass significantly increased in both sexes (P < 0.01) following RES and fat mass decreased in females following END (P = 0.019). The change in C-reactive protein following END was significantly different between sexes (F: -0.4 mg/L; M: +0.5 mg/L; P = 0.035). There were no differences between sexes in the proportion of individuals who responded positively to any variable following RES or END; differences between sexes were due to the magnitude of change. Males had a larger increase in V̇o_2peak following END and strength following RES. There were no sex differences in other CV risk factors. This suggests differences in physiological responses to strength and V̇o_2peak may not translate to changes in CV risk in healthy subjects.NEW & NOTEWORTHY This study investigated sex differences in cardiovascular risk factors in response to different exercise training modalities. Males had a larger improvement in peak oxygen consumption following endurance training and strength following resistance training compared with females. These changes in peak oxygen consumption and strength did not translate to changes in other cardiovascular risk factors. Despite the greater magnitude of change in males, there were no sex differences in the proportion of individuals who responded to training.

Sex Differences in RANTES (CCL5) in Patients With Intermediate Age-Related Macular Degeneration (AMD) and Controls With no AMD

Purpose

To determine if there are sex differences in levels of regulated upon activation, normal T cell expressed and secreted (RANTES) in patients with intermediate age-related macular degeneration (iAMD) and in controls with no AMD.

Methods

Patients with iAMD and controls defined by multi-modal imaging were recruited into a Colorado AMD registry. Plasma levels of the chemokine RANTES were measured using a multiplex assay. A nonparametric (rank-based) regression model was fit to RANTES with a sex by AMD category interaction.

Results

The plasma level of RANTES was significantly higher in the control group in comparison with the iAMD group. When moderated by sex, RANTES was significantly lower (P = 0.005) in males (median, 4525.6 pg/mL; interquartile range, 2589–7861 pg/mL) compared with females (median, 6686 pg/mL; interquartile range, 3485–12488 pg/mL) within the iAMD cohort. No significant difference was found in levels of RANTES between males and females in the control group.

Conclusions

We found that levels of RANTES were moderated by sex in cases with iAMD with lower levels in males compared with females. The findings illustrate the importance of including sex as a biological variable in AMD research. There is a need for further studies of RANTES, stratified by sex, in the advanced phenotypes of AMD.

Translational Relevance

The biomarker RANTES identified in the plasma of patients with iAMD reflects systemic alterations when stratified by sex.

The Roles of Carotenoid Consumption and Bioavailability in Cardiovascular Health

Carotenoids are natural pigments generally with a polyene chain consisting of 9-11 double bonds. In recent years, there has been increasing research interest in carotenoids because of their protective roles in cardiovascular diseases (CVDs). While the consumption of carotenoids may have a beneficial effect on CVDs, the literature shows inconsistencies between carotenoid consumption and reductions in the risk of CVDs. Therefore, this review aims to provide a summary of the association between dietary carotenoid intake and the risk of CVDs from published epidemiological studies. Meanwhile, to further elucidate the roles of carotenoid intake in CVD protection, this review outlines the evidence reporting the effects of carotenoids on cardiovascular health from randomized controlled trials by assessing classical CVD risk factors, oxidative stress, inflammatory markers and vascular health-related parameters, respectively. Given the considerable discrepancies among the published results, this review underlines the importance of bioavailability and summarizes the current dietary strategies for improving the bioavailability of carotenoids. In conclusion, this review supports the protective roles of carotenoids against CVDs, possibly by attenuating oxidative stress and mitigating inflammatory response. In addition, this review suggests that the bioavailability of carotenoids should be considered when evaluating the roles of carotenoids in CVD protection.

Longitudinal associations between C-reactive protein and cognitive performance in normative cognitive ageing and dementia

BACKGROUND

systemic inflammation appears to play an important role in the pathogenesis and expression of Alzheimer's disease and other dementias. Previous research has found that elevated levels of serum C-reactive protein (CRP) is associated with poorer cognitive functioning and increased risk for dementia. However, most studies are limited by single CRP measurements, which fail to capture long-term inflammatory exposures or dynamic changes in inflammation and cognition which may occur across repeated measurements.

METHODS

using data from 3,563 older adults aged 65-101 from the Health and Retirement Study, we examined bivariate changes in CRP and cognition measured repeatedly over a 10-year follow-up. Bivariate multilevel models estimated the effect of time-varying CRP on cognition among cognitively healthy older adults and in a subset of 427 participants who reported incident dementia onset during the follow-up period.

RESULTS

in cognitively healthy participants, CRP was associated with lower level of cognitive functioning, but not rate of change over time. This effect was significant in participants under 80 years of age (b = -0.09, standard error (SE) = 0.05, P = 0.04), but not in older participants. In participants with incident dementia, those with higher CRP experienced smaller rates of cognitive decline, leading up to dementia diagnosis.

CONCLUSIONS

elevated levels of CRP predict poorer cognition and increased dementia risk in cognitively healthy adults under the age of 80. Conversely, increased CRP may confer protective effects on cognition in the prodromal stage of dementia.

Impact of Fat Intake on Blood Glucose Control and Cardiovascular Risk Factors in Children and Adolescents with Type 1 Diabetes

Nutrition therapy is a cornerstone of type 1 diabetes (T1D) management. Glycemic control is affected by diet composition, which can contribute to the development of diabetes complications. However, the specific role of macronutrients is still debated, particularly fat intake. This review aims at assessing the relationship between fat intake and glycemic control, cardiovascular risk factors, inflammation, and microbiota, in children and adolescents with T1D. High fat meals are followed by delayed and prolonged hyperglycemia and higher glycated hemoglobin A1c levels have been frequently reported in individuals with T1D consuming high amounts of fat. High fat intake has also been associated with increased cardiovascular risk, which is higher in people with diabetes than in healthy subjects. Finally, high fat meals lead to postprandial pro-inflammatory responses through different mechanisms, including gut microbiota modifications. Different fatty acids were proposed to have a specific role in metabolic regulation, however, further investigation is still necessary. In conclusion, available evidence suggests that a high fat intake should be avoided by children and adolescents with T1D, who should be encouraged to adhere to a healthy and balanced diet, as suggested by ISPAD and ADA recommendations. This nutritional choice might be beneficial for reducing cardiovascular risk and inflammation.

The Cardiometabolic Health Benefits of Sauna Exposure in Individuals with High-Stress Occupations. A Mechanistic Review

Components of the metabolic syndrome (i.e., hypertension, insulin resistance, obesity, atherosclerosis) are a leading cause of death in the United States and result in low-grade chronic inflammation, excessive oxidative stress, and the eventual development of cardiometabolic diseases (CMD). High-stress occupations (HSO: firefighters, police, military personnel, first responders, etc.) increase the risk of developing CMD because they expose individuals to chronic and multiple stressors (i.e., sleep deprivation, poor nutrition habits, lack of physical activity, psychological stress). Interestingly, heat exposure and, more specifically, sauna bathing have been shown to improve multiple markers of CMD, potentially acting as hormetic stressors, at the cellular level and in the whole organism. Therefore, sauna bathing might be a practical and alternative intervention for disease prevention for individuals with HSO. The purpose of this review is to detail the mechanisms and pathways involved in the response to both acute and chronic sauna bathing and collectively present sauna bathing as a potential treatment, in addition to current standard of care, for mitigating CMD to both clinicians and individuals serving in HSO.

Association of inflammatory mediators with frailty status in older adults: results from a systematic review and meta-analysis

Frailty is a geriatric syndrome defined as a status of extreme vulnerability to stressors, leading to a higher risk of negative health-related outcomes. "Inflammaging", an age-related state of low-grade chronic inflammation, is characterized by an increased concentration of pro-inflammatory cytokines and acute phase proteins. Inflammaging has been postulated as an underlying mechanism of frailty, and several studies tested the relationship between frailty and concentration of inflammatory mediators. The aim of this systematic review and meta-analysis was to test whether inflammatory mediators are overproduced in frail older adults. Among the 758 articles identified in the literature search, 50 were included in the systematic review, and 39 in the three meta-analyses, i.e., C-reactive protein (CRP), interleukin 6 (IL6), and tumor necrosis factor α. To reduce heterogeneity, meta-analyses were restricted to studies identifying frailty by the Fried et al. [1] [J. Gerontol. A. Biol. Sci. Med. Sci. 56, M146-56] phenotypic criteria. Quantitative analyses measuring the association between frailty and biomarker concentrations showed significant differences when frail subjects were compared to non-frail and pre-frail subjects for CRP and IL6. This work established strong association between inflammatory biomarkers and frailty, confirming the role of age-related chronic inflammation in frailty development.

Interactions among Obstructive Sleep Apnea Syndrome Severity, Sex, and Obesity on Circulatory Inflammatory Biomarkers in Patients with Suspected Obstructive Sleep Apnea Syndrome: A Retrospective, Cross-Sectional Study

The interaction among obstructive sleep apnea syndrome (OSAS) severity, sex, and obesity on cardiovascular risk as determined by serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) remains unclear. Therefore, this study aimed to analyze individual associations between these three OSAS characteristics and three cardiovascular biomarkers and to determine whether the relationship was affected by other features in patients with suspected OSAS. For all participants (n = 100), OSAS severity and sex had an interaction effect on IL-6 level (p = 0.030). Specifically, the male patients (p = 0.005) with severe OSAS had higher IL-6 levels than those with normal to moderate OSAS, but this relationship was not significant in the female patients (p = 0.438). Moreover, in patients with normal to moderate OSAS (p = 0.004), but not in those with severe OSAS (p = 0.824), the female patients had higher IL-6 levels than the male patients. Both CRP (p = 0.001) and IL-6 (p = 0.000) levels were higher in the obese group than in the non-obese group independently of OSAS severity and sex. The three features had no effects on TNF-α level individually and interactively. Our findings suggest that circulatory inflammatory markers should be comprehensively evaluated in this population and that treatment and preventive therapies should be modified accordingly.

Precision Medicine and Cardiovascular Health: Insights from Mendelian Randomization Analyses

Cardiovascular disease (CVD) is considered a primary driver of global mortality and is estimated to be responsible for approximately 17.9 million deaths annually. Consequently, a substantial body of research related to CVD has developed, with an emphasis on identifying strategies for the prevention and effective treatment of CVD. In this review, we critically examine the existing CVD literature, and specifically highlight the contribution of Mendelian randomization analyses in CVD research. Throughout this review, we assess the extent to which research findings agree across a range of studies of differing design within a triangulation framework. If differing study designs are subject to non-overlapping sources of bias, consistent findings limit the extent to which results are merely an artefact of study design. Consequently, broad agreement across differing studies can be viewed as providing more robust causal evidence in contrast to limiting the scope of the review to a single specific study design. Utilising the triangulation approach, we highlight emerging patterns in research findings, and explore the potential of identified risk factors as targets for precision medicine and novel interventions.

Reticulated Platelets as Predictor of Myocardial Injury and 30 Day Mortality After Non-cardiac Surgery

OBJECTIVE

A pre-operative marker for identification of patients at risk of peri-operative adverse events and 30 day mortality might be the percentage of young, reticulated platelets (pRP). This study aimed to determine the predictive value of pre-operative pRP on post-operative myocardial injury (PMI) and 30 day mortality, in patients aged ≥ 60 years undergoing moderate to high risk non-cardiac surgery.

METHODS

The incidence of PMI (troponin I > 0.06 μg/L) and 30 day mortality was compared for patients with normal and high pRP (≥2.82%) obtained from The Utrecht Patient Orientated Database. The predictive pRP value was assessed using logistic regression. A prediction model for PMI or 30 day mortality with known risk factors was compared with a model including increased pRP using the area under the receiving operator characteristics curve (AUROC).

RESULTS

In total, 26.5% (607/2289) patients showed pre-operative increased pRP. Increased pRP was associated with more PMI and 30 day mortality compared with normal pRP (36.1% vs. 28.3%, p < .001 and 8.6% vs. 3.6%, p < .001). The median pRP was higher in patients suffering PMI and 30 day mortality compared with not (2.21 [IQR: 1.57-3.11] vs. 2.07 [IQR: 1.52-1.78], p = .002, and 2.63 [IQR: 1.76-4.15] vs. 2.09 [IQR: 1.52-3.98], p < .001). pRP was independently related to PMI (OR: 1.28 [95% CI: 1.04-1.59], p = .02) and 30 day mortality (OR: 2.35 [95% CI: 1.56-3.55], p < .001). Adding increased pRP to the predictive model of PMI or 30 day mortality did not increase the AUROC 0.71 vs. 0.72, and 0.80 vs. 0.81.

CONCLUSION

In patients undergoing major non-cardiac surgery, increased pre-operative pRP is related to 30 day mortality and PMI.

Effect of whole foods and dietary patterns on markers of subclinical inflammation in weight-stable overweight and obese adults: a systematic review

Context

Reduction of subclinical inflammation is a potential target for chronic disease management. Adiposity is a known modifier of meta-inflammation; however, the influence of dietary factors is less clear.

Objective

This review examines evidence from human trials evaluating effects of whole foods or dietary patterns on circulating inflammatory markers in weight-stable overweight and obese adults. It is the first review to investigate effects of diet on inflammation, independent of changes in adiposity.

Data Sources

The Ovid MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched.

Data Extraction

Data extraction was conducted using the Cochrane Collaboration Handbook for Systematic Reviews of Interventions.

Data Analysis

Study quality was evaluated using the Cochrane Collaboration Risk of Bias Assessment tool. Thirty-three studies were included assessing effects of 17 foods and dietary patterns on 39 inflammatory markers.

Conclusions

Overall, foods and dietary patterns were not found to have significant effects on inflammatory markers in weight-stable individuals. Inconsistencies among studies were largely due to methodological limitations. Future research should invest in longer intervention periods and standardization of inflammatory marker panels paired with novel technologies, while ensuring anthropometric measures are monitored and adequately controls are used.

Systematic Review Registration

Prospero registration number CRD42017067765.

Mendelian randomization analysis of C-reactive protein on colorectal cancer risk

BACKGROUND

Chronic inflammation is a risk factor for colorectal cancer (CRC). Circulating C-reactive protein (CRP) is also moderately associated with CRC risk. However, observational studies are susceptible to unmeasured confounding or reverse causality. Using genetic risk variants as instrumental variables, we investigated the causal relationship between genetically elevated CRP concentration and CRC risk, using a Mendelian randomization approach.

METHODS

Individual-level data from 30 480 CRC cases and 22 844 controls from 33 participating studies in three international consortia were used: the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT) and the Colon Cancer Family Registry (CCFR). As instrumental variables, we included 19 single nucleotide polymorphisms (SNPs) previously associated with CRP concentration. The SNP-CRC associations were estimated using a logistic regression model adjusted for age, sex, principal components and genotyping phases. An inverse-variance weighted method was applied to estimate the causal effect of CRP on CRC risk.

RESULTS

Among the 19 CRP-associated SNPs, rs1260326 and rs6734238 were significantly associated with CRC risk (P = 7.5 × 10-4, and P = 0.003, respectively). A genetically predicted one-unit increase in the log-transformed CRP concentrations (mg/l) was not associated with increased risk of CRC [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97, 1.12; P = 0.256). No evidence of association was observed in subgroup analyses stratified by other risk factors.

CONCLUSIONS

In spite of adequate statistical power to detect moderate association, we found genetically elevated CRP concentration was not associated with increased risk of CRC among individuals of European ancestry. Our findings suggested that circulating CRP is unlikely to be a causal factor in CRC development.

Association between Phytate Intake and C-Reactive Protein Concentration among People with Overweight or Obesity: A Cross-Sectional Study Using NHANES 2009/2010

Phytic acid has anti-oxidant properties, which are useful in addressing inflammation. This study investigated the relationship between dietary phytate intake and C-reactive protein (CRP) levels among individuals that are overweight or obese. The study used cross-sectional data from the 2009/2010 National Health and Nutrition Examination Survey (NHANES) for 3152 subjects. Phytate intake was estimated using phytate content of foods reported by the International Zinc Nutrition Consultative Group (IZiNCG). Logistic regression was used to determine the associations between phytate intake and odds of elevated CRP concentration (CRP >3 mg/L), adjusting for confounders. Medians (and 95% CIs) for phytate intake and CRP concentration were 0.66 (0.64, 0.68) g/d and 1.4 (1.2, 1.5) mg/L, respectively. Phytate intake was higher in males than females, higher in non-Hispanic Whites than non-Hispanic Blacks and Mexican Americans, and lower in current smokers than former smokers and nonsmokers. Higher phytate intake was associated with lower odds of elevated CRP (OR = 0.66; 95% CI = 0.52, 0.84). Women, as well as current and former smokers with overweight or obesity, had higher odds of elevated CRP concentration. These results imply that individuals with high phytate intake, particularly among those with overweight or obesity, have lower risk for inflammation-related chronic diseases such as cardiovascular diseases.

Association between serum high-sensitivity C-reactive protein levels and erectile dysfunction: a cross-sectional study of Chinese male population

Inflammation has been known to affect endothelial function and is involved in the progression of erectile dysfunction (ED). Thus, our present study was conducted to investigate the association between inflammatory marker high-sensitivity C-reactive protein (hs-CRP) and ED in a Chinese male population. A total of 1515 participants with anthropometric measurements, serum analyses and hs-CRP values available were included in our cross-sectional study. Data involving socioeconomic and lifestyle factors were also collected. ED was assessed by the 5-item International Index Erectile Function (IIEF-5), and hs-CRP levels were measured by the immunoturbidimetric assay. Logistic regression was applied to estimate the association between the serum hs-CRP and the risk of ED, and receiver operating characteristics (ROC) curve analysis was performed to identify the predictive value of hs-CRP. Serum hs-CRP levels were significantly higher in ED patients, and increased progressively with the incremental severity of ED (P < 0.001 for trend). In the multivariate-adjusted model, men in the highest quartile of hs-CRP level versus those in the lowest quartile had a 50% increased likelihood for ED (OR = 1.50; 95% CI = 1.08–2.08). When subjects were stratified by age, the risk of ED was more prominently in the middle-aged and elderly men. Based on the ROC analysis, serum hs-CRP has a poor diagnostic value for ED with an AUC of 0.58 (95% CI: 0.56–0.61) but has a good diagnostic performance for differentiating severe ED (AUC: 0.79; 95% CI: 0.77–0.81). Our study indicates that increased serum hs-CRP levels are associated with the severity of ED and an increased ED risk in a Chinese male population. These findings suggest that hs-CRP may be of value as an inflammatory marker for the assessment of ED risk and may play an important role in the etiology of ED.

Subclinical Atherosclerosis in Patients With Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Cardiovascular (CV) risk in type 1 diabetes mellitus (T1DM) is increased. In this study, we evaluated the differences in major markers of CV risk between patients with T1DM and healthy controls by a systematic review and meta-analysis. Literature from PubMed, EMBASE, and The Cochrane Library comparing CV risk markers between patients with T1DM and controls was obtained. The overall standard mean differences (SMDs) of carotid intima–media thickness (cIMT), endothelium-dependent flow-mediated dilation (FMD%), carotid-femoral pulse wave velocity (cf-PWV), and glyceryl trinitrate-mediated dilatation (GTN%) with its 95% confidence interval (CI) between patients with T1DM and control groups were calculated using fixed-effect or random-effect model. Heterogeneity was evaluated using the Cochran Q and I2 statistics. The results showed that patients with T1DM had a significantly greater cIMT (SMD: 0.89; 95% CI, 0.69-1.09; P < .001), significantly lower FMD% (SMD: −1.45%; 95% CI, −1.74 to −1.17; P < .001), significantly increased cf-PWV (SMD: 0.57; 95% CI, 0.03-1.11; P < .001), and significantly decreased GTN% (SMD: −1.11; 95% CI, −1.55 to −0.66; P < .001) than controls. Our results support the current evidence for an elevated CV burden in patients with T1DM and affirm the clinical utility of markers of subclinical atherosclerosis in the management of these patients.

The association between exposure to different aspects of shift work and metabolic risk factors in health care workers, and the role of chronotype

Objective

Shift work has been linked to cardio-metabolic diseases, but insight into different shift work-related aspects and chronotype of shift workers and their relation with metabolic risk factors is limited. This study examined the association between current shift work status, frequency and duration of night shift work, chronotype, and metabolic risk factors in a population of health care workers.

Methods

Anthropometrics, questionnaires, and blood samples were collected from 503 shift working and 93 non-shift working health care workers employed in hospitals. Body mass index, waist circumference, cholesterol (total, HDL, LDL), triglycerides, and high-sensitivity C-reactive protein were measured. Associations of current shift work, frequency (non-night shift worker, 1–2, 3–4, ≥5 night shifts/month) and duration of night shift work (non-night shift workers, <10, 10–19, ≥20 years), and shift workers’ chronotype, with metabolic risk factors were studied using linear regression analysis.

Results

Compared to non-shift workers, shift workers’ total cholesterol level was 0.38 mmol/L lower (95%-CI = -0.73 –-0.04) and LDL cholesterol was 0.34 mmol/L lower (95%-CI = -0.60 –-0.08). For all other metabolic risk factors, no differences were found. The association between shift work and LDL cholesterol was especially found among shift workers working night shifts for ≥20 years (B = -0.49 (95%-CI = -0.78 –-0.19)). No differences were found for night shift frequency and chronotype.

Conclusion

In this population of health care workers employed in hospitals, no evidence for differences in metabolic risk factors was observed that could underlie a link between shift work and cardio-metabolic diseases. Further research using different aspects of shift work to study the association with metabolic risk factors is recommended.

Biochemical Assessment: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

The Tehran Lipid and Glucose Study (TLGS) is a community-based study to reveal the frequency of non-communicable diseases (NCDs) in Tehran's population. This research consists of two main parts, a cross-sectional study on the prevalence of cardiovascular risk factors and a 20-year-ongoing prospective cohort study, which was initiated in 1999 in several phases with an approximate duration of 3.6 years, and is still ongoing. The aim of the present study is review the 20 year biochemical findings of the TLGS related to the NCDs in a large sample.

METHODS

All articles on biochemical assessments derived from the TLGS from the earliest publications (2002) until 30 January 2018 were reviewed for their findings on different risk factors of NCDs.

RESULTS

According to the TLGS findings high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), homocysteine (Hcy), age, smoking, hypertension, and obesity were the most important risk factors of cardiovascular diseases (CVD). It was illustrated that in subjects with abdominal obesity, the hs-CRP and IL-6 serum levels were higher than in normal subjects. The most appropriate prognostic indexes and associations were for hs-CRP, IL-6, and Hcy with abdominal obesity, waist circumference, WHtR, and wrist circumference, respectively. Previous studies have demonstrated a direct relationship between obesity and serum levels of inflammatory factors.

CONCLUSIONS

According to the results of TLGS, serum levels of biochemical risk factors such as hs-CRP, IL-6, and Hcy could be beneficial in early diagnosis and effective treatment of cardiovascular, obesity and other metabolic diseases.

Immunological alterations in frail older adults: A cross sectional study

Frailty is a progressive physiologic decline in multiple body systems, characterized by loss of function, loss of physiologic reserve, and increased vulnerability to disease and death. This condition is induced by a complex and multifactorial interaction between genetic, biological, physical, psychological and environmental factors. To understand the interplay between the age-related decline of the immune response, and the upregulation of the inflammatory response, the so called inflammaging, we investigated the role of different inflammatory mediators on frailty status in the elderly. The study was performed in a population of 180 older adults (≥65 years), who were classified according to Fried's frailty phenotype. Plasma concentrations of neopterin, tryptophan, kynurenine, phenylalanine, tyrosine as well as kynurenine/tryptophan (Kyn/Trp) and phenylalanine/tyrosine (Phe/Tyr) ratios were analyzed as immune stimulation biomarkers. In addition, nitrite and C-reactive protein levels were measured as indicators of nitric oxide production and acute inflammation, respectively. Significant increases in neopterin, C-reactive protein and Kyn/Trp ratio, and decreases in tryptophan and nitrite concentrations in frail individuals compared with non-frail group were found. Both Kyn/Trp and Phe/Tyr ratios were significantly and positively correlated with neopterin. A positive correlation between kynurenine and tryptophan was also observed. Four parameters, i.e., neopterin, tryptophan, nitrite and C-reactive protein, were found to be strongly related to frailty status, although only nitrite confirmed its role of predictor after multiple regression analysis, supporting its use as a potential biomarker of frailty. Further investigation is required to strengthen the consistence and reproducibility of these findings, and to establish this parameter as a clinical biomarker of frailty.

Current Helicobacter pylori infection is significantly associated with subclinical coronary atherosclerosis in healthy subjects: A cross-sectional study

Helicobacter pylori is a gastrointestinal pathogen known to be associated with cardiovascular disease (CVD). However, most analyses about the effect of H. pylori infection have been done in patients with a history of CVD but not in healthy subjects. We evaluated the association between H. pylori infection and subclinical atherosclerosis by using cardiac multidetector computed tomography (MDCT) in healthy subjects without previous CVD. From December 2007 to February 2014, 463 subjects who underwent the rapid urease test (CLO test), pulse-wave velocity (PWV) measurement, and MDCT for a self-referred health check-up were enrolled to this study. Helicobacter pylori infection was defined on the basis of CLO test positivity on endoscopic gastric biopsy. Significant coronary artery stenosis was defined as ≥50% stenosis in any of the major epicardial coronary vessel on MDCT. The CLO-positive subjects had a lower high-density lipoprotein-cholesterol (HDL-cholesterol) level compared to the CLO-negative subjects. The incidence of significant coronary stenosis was higher in the CLO-positive group (7.6% vs. 2.9%, P = 0.01). Furthermore, the number of subjects with coronary artery calcium score >0 and log{(number of segments with plaque)+1} were also significantly higher in the CLO-positive group. However, there was no statistical difference in the number of subjects with coronary artery calcium score >100, the prevalence of any plaque nor the plaque characteristics (calcified, mixed, or soft). Pulse-wave velocity (PWV) was neither associated with CLO test positivity. The CLO-positive group was 3-fold more likely to have significant coronary artery stenosis even after adjusting for confounding factors (adjusted odds ratio 2.813, 95% confidence interval 1.051–7.528, P = 0.04). In a healthy population, current H. pylori infection was associated with subclinical but significant coronary artery stenosis. The causal relationship between H. pylori infection and subclinical atherosclerosis in a “healthy” population remains to be investigated in the future.

Associations of aerobic and strength exercise with clinical laboratory test values

OBJECTIVES

Physical exercise may affect levels of blood-based biomarkers. However, exercise status is seldom considered in the interpretation of laboratory results. This study reports the associations between habitual exercise participation and clinical laboratory test results.

METHODS

The effects of days per week of aerobic and strength exercise participation on laboratory test results for 26 biomarkers in young adults aged 18 to 34 years (n = 80,111) were evaluated using percentile distribution analyses and multivariate regression.

RESULTS

In both men and women, more days per week of either aerobic or strength exercise were significantly associated with lower levels of glucose, hemoglobin A1c, LDL cholesterol, total cholesterol, triglycerides, estimated glomerular filtration rate, globulin, and C-reactive protein, and significantly higher levels of HDL cholesterol, creatinine, iron, and percent saturation (all p < .05). Type of exercise or gender influenced the observed relationships with exercise frequency for total cholesterol, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, uric acid, bilirubin, and iron binding capacity.

CONCLUSIONS

Physical exercise shifted the distribution of results into the direction suggestive of better health. Reported relationships may help clinicians and patients to better understand and interpret laboratory results in athletic populations and possibly re-evaluate interpretation of reference intervals for physically active populations.

Interplay between PAPP-A, inflammation and adiposity in patients with angiographically proven acute coronary syndrome (ACS)

Introduction Studies conducted in the recent past have demonstrated the role of inflammation, obesity and dysfunctional insulin signaling as contributing factors in the pathogenesis of acute coronary syndrome (ACS). However, pharmacological interventions targeting a single pathway have not proven useful in the long run. This indicates that a synergism occurs between the various risk factors and hence calls for a combinatorial approach. This study was planned to study the interplay, if any, between pregnancy associated plasma protein-A (PAPP-A), inflammation and adiposity in patients with ACS. Materials and methods The study was conducted in a tertiary care hospital in Delhi. The study population consisted of 128 subjects, divided into two groups. The control group consisted of 64 healthy subjects without ACS. Cases consisted of 64 subjects with angiographically proven ACS cases. PAPP-A and high sensitivity C-reactive protein (hs-CRP) were estimated by enzyme-linked immunosorbent assay (ELIZA) kits. Results The mean level of PAPP-A and hs-CRP were significantly higher in cases as compared to the controls. A positive correlation of PAPP-A was observed with hs-CRP, insulin, ApoB and Lp(a). The relative risk for ACS was 14.2 with a p value of <0.001 when all the three parameters - hs-CRP, PAPP-A and body mass index (BMI) were considered together. This was significantly higher when each risk factor was assessed standalone. Conclusions Our study results suggest a possible interplay between chronic inflammation, obesity and plaque instability among patients with ACS. This interaction can accelerate the process of plaque rupture in patients with increased BMI as compare to those patients with low/normal BMI.

Using multiple biomarkers and determinants to obtain a better measurement of oxidative stress: a latent variable structural equation model approach

PURPOSE

Since oxidative stress involves a variety of cellular changes, no single biomarker can serve as a complete measure of this complex biological process. The analytic technique of structural equation modeling (SEM) provides a possible solution to this problem by modelling a latent (unobserved) variable constructed from the covariance of multiple biomarkers.

METHODS

Using three pooled datasets, we modelled a latent oxidative stress variable from five biomarkers related to oxidative stress: F₂-isoprostanes (FIP), fluorescent oxidation products, mitochondrial DNA copy number, γ-tocopherol (Gtoc) and C-reactive protein (CRP, an inflammation marker closely linked to oxidative stress). We validated the latent variable by assessing its relation to pro- and anti-oxidant exposures.

RESULTS

FIP, Gtoc and CRP characterized the latent oxidative stress variable. Obesity, smoking, aspirin use and β-carotene were statistically significantly associated with oxidative stress in the theorized directions; the same exposures were weakly and inconsistently associated with the individual biomarkers.

CONCLUSIONS

Our results suggest that using SEM with latent variables decreases the biomarker-specific variability, and may produce a better measure of oxidative stress than do single variables. This methodology can be applied to similar areas of research in which a single biomarker is not sufficient to fully describe a complex biological phenomenon.

Low-Grade Inflammation Is Associated with Susceptibility to Infection in Healthy Men: Results from the Danish Blood Donor Study (DBDS)

INTRODUCTION

The aim of this study was to examine whether low-grade inflammation (LGI) is associated with a subsequently increased risk of infection.

METHODS

We included 15,754 healthy participants from the Danish Blood Donor Study, who completed a questionnaire on health-related items. LGI was defined as a C-reactive protein level between 3 and 10 mg/L. Infections were identified by ICD-10 codes in the Danish National Patient Register and ATC-codes in the Danish Prescription Register. Multivariable Cox proportional hazard analysis was used as the statistical model.

RESULTS

During 53,302 person-years of observation, 571 participants were hospitalized for infection. Similarly, during 26,125 person-years of observation, 7,276 participants filled a prescription of antimicrobials. LGI was associated with increased risk of hospital-based treatment for infection only among men (hazard ratio = 1.60, 95% confidence interval (CI): 1.10-2.34) and specifically infections were abscesses and infections of the skin and subcutaneous tissue. Similarly, LGI was associated with the overall use of antimicrobials among men, and particularly with phenoxymethylpenicillin and broad-spectrum antimicrobials for treatment of urinary tract infections. The difference between men and women was not statistically significant.

CONCLUSIONS

In a large cohort of healthy individuals, LGI was associated with an increased risk of infection among healthy male blood donors.

Göttingen minipig model of diet-induced atherosclerosis: influence of mild streptozotocin-induced diabetes on lesion severity and markers of inflammation evaluated in obese, obese and diabetic, and lean control animals

Background

From a pharmacological perspective, readily-available, well-characterized animal models of cardiovascular disease, including relevant in vivo markers of atherosclerosis are important for evaluation of novel drug candidates. Furthermore, considering the impact of diabetes mellitus on atherosclerosis in human patients, inclusion of this disease aspect in the characterization of a such model, is highly relevant. The objective of this study was to evaluate the effect of mild streptozotocin-induced diabetes on ex- and in vivo end-points in a diet-induced atherosclerotic minipig model.

Methods

Castrated male Göttingen minipigs were fed standard chow (CD), atherogenic diet alone (HFD) or with superimposed mild streptozotocin-induced diabetes (HFD-D). Circulating markers of inflammation (C-reactive protein (CRP), oxidized low-density lipoprotein (oxLDL), plasminogen activator inhibitor-1, lipid and glucose metabolism were evaluated together with coronary and aortic atherosclerosis after 22 or 43 diet-weeks. Group differences were evaluated by analysis of variance for parametric data and Kruskal–Wallis test for non-parametric data. For qualitative assessments, Fisher’s exact test was applied. For all analyses, p < 0.05 was considered statistically significant.

Results

Overall, HFD and HFD-D displayed increased CRP, oxLDL and lipid parameters compared to CD at both time points. HFD-D displayed impaired glucose metabolism as compared to HFD and CD. Advanced atherosclerotic lesions were observed in both coronary arteries and aorta of HFD and HFD-D, with more advanced plaque findings in the aorta but without differences in lesion severity or distribution between HFD and HFD-D. Statistically, triglyceride was positively (p = 0.0039), and high-density lipoprotein negatively (p = 0.0461) associated with aortic plaque area.

Conclusions

In this model, advanced coronary and aortic atherosclerosis was observed, with increased levels of inflammatory markers, clinically relevant to atherosclerosis. No effect of mild streptozotocin-induced diabetes was observed on plaque area, lesion severity or inflammatory markers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0670-2) contains supplementary material, which is available to authorized users.

Dietary inflammatory index is related to asthma risk, lung function and systemic inflammation in asthma

BACKGROUND

Asthma prevalence has increased in recent years, and evidence suggests that diet may be a contributing factor. Increased use of processed foods has led to a decrease in diet quality, which may be creating a pro-inflammatory environment, thereby leading to the development and/or progression of various chronic inflammatory diseases and conditions. Recently, the dietary inflammatory index (DII) has been developed and validated to assess the inflammatory potential of individual diets.

OBJECTIVE

This study aimed to examine the DII in subjects with asthma compared to healthy controls and to relate the DII to asthma risk, lung function and systemic inflammation.

METHODS

Subjects with asthma (n = 99) and healthy controls (n = 61) were recruited. Blood was collected and spirometry was performed. The DII was calculated from food frequency questionnaires administered to study subjects.

RESULTS

The mean DII score for the asthmatics was higher than the mean DII score for healthy controls (- 1.40 vs. - 1.86, P = 0.04), indicating that their diets were more pro-inflammatory. For every 1 unit increase in DII score, the odds of having asthma increased by 70% (OR: 1.70, 95% CI: 1.03, 2.14; P = 0.040). FEV1 was significantly associated with DII score (β = - 3.44, 95% CI: - 6.50, - 0.39; P = 0.020), indicating that for every 1 unit increase in DII score, FEV1 decreased by 3.44 times. Furthermore, plasma IL-6 concentrations were positively associated with DII score (β = 0.13, 95% CI: 0.05, 0.21; P = 0.002).

CONCLUSION AND CLINICAL RELEVANCE

As assessed using the DII score, the usual diet consumed by asthmatics in this study was pro-inflammatory relative to the diet consumed by the healthy controls. The DII score was associated with increased systemic inflammation and lower lung function. Hence, consumption of pro-inflammatory foods may contribute to worse asthma status, and targeting an improvement in DII in asthmatics, as an indicator of suitable dietary intake, might be a useful strategy for improving clinical outcomes in the disease.

Impact of Framingham risk score, flow-mediated dilation, pulse wave velocity, and biomarkers for cardiovascular events in stable angina

Although the age-adjusted Framingham risk score (AFRS), flow-mediated dilation (FMD), brachial-ankle pulse wave velocity (baPWV), high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and free fatty acid (FFA) can predict future cardiovascular events (CVEs), a comparison of these risk assessments for patients with stable angina has not been reported. We enrolled 203 patients with stable angina who had been scheduled for coronary angiography (CAG). After CAG, 134 patients showed significant coronary artery disease. During 4.2 yr follow-up, 36 patients (18%) showed CVEs, including myocardial infarction, de-novo coronary artery revascularization, in-stent restenosis, stroke, and cardiovascular death. ROC analysis showed that AFRS, FMD, baPWV, and hsCRP could predict CVEs (with AUC values of 0.752, 0.707, 0.659, and 0.702, respectively, all P<0.001 except baPWV P=0.003). A Cox proportional hazard analysis showed that AFRS and FMD were independent predictors of CVEs (HR, 2.945; 95% CI, 1.572-5.522; P=0.001 and HR, 0.914; 95% CI, 0.826-0.989; P=0.008, respectively). However, there was no difference in predictive power between combining AFRS plus FMD and AFRS alone (AUC 0.752 vs. 0.763; z=1.358, P=0.175). In patients with stable angina, AFRS and FMD are independent predictors of CVEs. However, there is no additive value of FMD on the AFRS in predicting CVEs.

Maternal diet-induced obesity and offspring cardiovascular health

It is widely recognized that environmental insults during adulthood including smoking, lack of exercise and a poor diet increases an individual's risk of cardiovascular disease (CVD). However, research initiated over the last two decades has highlighted that our risk of CVD can be programmed following adverse exposures during early development. Such adverse exposures may include, undernutrition, placental insufficiency, hypoxia, overnutrition and obesity. This review aims to address the current Western obesity crisis by addressing the long-term impact of maternal overnutrition and obesity on the offspring's future risk of CVD. Although current human studies have observed the presence of adverse CVD markers in children born to obese mothers, animal models have proved vital in understanding the underlying mechanisms involved. Mechanisms suggested to be involved in the programming of CVD in the offspring include increased oxidative stress, inflammation, lipotoxicity and epigenetics. CVD remains the greatest cause of death worldwide, therefore further understanding of the mechanisms mediating these effects is important in the development of intervention strategies.

Genetic variants in C-reactive protein and ischemic stroke susceptibility

Considerable discrepancies in the previously reported associations of the C-reactive protein (CRP) gene variants and ischemic stroke (IS) risk prompted us to perform this meta-analysis. We selected the fixed effects Mantel-Haenszel method to estimate the risk of IS [OR (odds ratio) along with its 95 % CI (confidence interval)] in relation to the CRP variants (-717 A > G, 1444 C > T). Heterogeneity test, influence analysis and publication bias test were appropriately performed using respective methods. We analyzed 1,926 IS patients and 2,678 controls and found the -717 A > G variant was not significantly associated with overall IS risk. Subsequent analysis of the 1444 C > T variant involving 3,278 samples similarly revealed no significant association with IS. There was no substantial heterogeneity or publication bias in this analysis. Our meta-analysis may provide first evidence showing that genetic variants within the CRP locus are unlikely to modulate risk of IS.

Dietary carotenoids are associated with cardiovascular disease risk biomarkers mediated by serum carotenoid concentrations

Hyperlipidemia and elevated circulating C-reactive protein (CRP) and total homocysteine (tHcy) concentrations are cardiovascular disease (CVD) risk factors. Previous studies indicated that higher serum carotenoid concentrations were inversely associated with some of these biomarkers. However, whether dietary carotenoid intake is inversely associated with these CVD risk biomarkers is not well known. We assessed the associations between individual dietary carotenoid intake and CVD risk biomarkers and tested whether the serum carotenoid concentrations explain (mediate) or influence the strength of (moderate) the associations, if any association exists. Dietary data collected from 2 24-h dietary recalls and serum measurements in adult men (n = 1312) and women (n = 1544) from the NHANES 2003-2006 were used. Regression models designed for survey analysis were used to examine the associations between individual dietary carotenoids and log-transformed blood cholesterol, CRP, and tHcy. The corresponding individual serum carotenoid concentration was considered as mediator (and moderator if applicable). After adjustment for covariates, significant inverse associations with LDL cholesterol were observed for dietary β-carotene (P < 0.05) and lutein + zeaxanthin (P < 0.001), and with tHcy for dietary β-carotene (P < 0.05), lycopene (P < 0.05), and total carotenoids (P < 0.05). Dietary lutein + zeaxanthin intake was also positively associated with HDL cholesterol concentrations (P < 0.01). Most of these associations were null after additional adjustment for corresponding serum carotenoid concentrations, indicating the complete mediation effects of serum carotenoids. Serum β-carotene significantly moderated the associations between dietary β-carotene and CRP (P-interaction < 0.05), and quartile 4 of dietary β-carotene was associated with lower CRP concentrations only among participants with serum β-carotene > 0.43 μmol/L. In this population-based cross-sectional study, serum carotenoids were mediators of dietary carotenoids and CVD risk biomarker associations. Serum β-carotene was also a moderator of the dietary β-carotene and CRP association. These findings may help in the design of future intervention studies on dietary carotenoids in the prevention of CVD.

Inflammation and echocardiographic parameters of ventricular hypertrophy in a cohort with preserved cardiac function

OBJECTIVE

To investigate the association between inflammation and selective echocardiographic parameters (EP) characteristic for ventricular hypertrophy in cross-sectional and longitudinal population-based analyses.

METHODS

Baseline (711 men, 659 women: 45-83 years) and 4-year follow-up data (622 men, 540 women) of the prospective, population-based CARdio-vascular disease, Living and Ageing in Halle (CARLA)study after exclusion of participants with cardiacvascular diseases were analysed. Inflammation parameters: soluble tumour necrosis factor receptor 1 (sTNF-R1), high-sensitivity C reactive protein (hsCRP) and interleukin 6 (IL-6). EPs: left ventricular mass (LVM), left atrial systolic dimension (LADS), interventricular septum diameter (IVSD), posterior wall dimension (PWD), left ventricular diastolic diameter (LVDD), ejection fraction according to Teichholz (EF). For the longitudinal analyses baseline to follow-up differences were considered. Effect sizes were determined by using multiple linear regression and mixed models. Missing values were replaced by means of multiple imputations.

RESULTS

Men had higher sTNF-R1 levels; means of hsCRP and IL-6 were similar in men and women. In multiple regression models, sTNF-R1 was associated with LADS (1.4 mm/1000 pg/mL sTNF-R1, 95% CI 0.6 to 2.1) in men. Respecting confounder hsCRP was associated with LVM (5.2 g/10 mg/L hsCRP, 95% CI 1.6 to 8.8), IVSD (0.2 mm/10 mg/L hsCRP, 95% CI 0 to 0.3) and PWD (0.2 mm/10 mg/L hsCRP, 95% CI 0.1 to 0.3) in women, while there were no relevant effects in analysis of IL-6 in both sexes. The baseline to follow-up change in EPs was not relevantly associated with sTNF-R1, hsCRP or IL-6.

CONCLUSIONS

STNF-R1, hsCRP and IL-6 were inadequate predictors for structural changes of the heart at follow-up, while weak cross-sectional associations are restricted to certain EPs and depend on sex.

C-reactive protein and the biology of disease

The C-reactive protein (CRP) is a plasma protein of hepatic origin, belonging to pentraxin family and forms a major component of any inflammatory reaction. A key component of the innate immunity pathway, the concentration of CRP may rapidly increase to levels more than 1,000-folds above normal values as a consequence to tissue injury or infection. Although functioning as a classical mediator of innate immunity, it functions via interaction of components of both humoral and cellular effector systems of inflammation. Initially considered as an acute-phase marker in tissue injury, infection and inflammation, it now has a distinct status of a disease marker in cardiovascular diseases and is well known of its clinical and pathological significance. The present torrent of studies in a large number of diseases and associated conditions has highly elucidated the role of CRP as a therapeutic and research reagent. In this review, we focus our attention to role of CRP in health and disease. The future prospect of this review lies in the applicability of CRP as a molecule in understanding and monitoring of the biology of disease.

C-reactive protein + 1059 G>C polymorphism in type 2 diabetes and coronary artery disease patients

Human C-reactive protein (CRP) is an acute phase reactant involved in chronic and acute inflammation. CRP is associated with metabolic syndrome, obesity, atherosclerosis, unstable angina, insulin resistance and diabetes. The present study evaluates the association of + 1059 G>C silent polymorphism in exon 2 of CRP gene in 581 cases [CAD (206), T2D (266), T2D with CAD (109)] and 235 controls in the population of Punjab (North-West India). The frequency of + 1059 G allele is highest in CAD (98.3%) followed by T2D (98.1%), T2D + CAD cases (97.7%) and controls (94.7%). G-allele is associated with increased risk of T2D [P = 0.003, OR = 2.93 (1.39–6.17)] and CAD [P = 0.004, OR = 3.25 (1.39–7.60)] in comparison to controls. Recessive model shows that GG genotype increases the risk of CAD by 4 fold (P = 0.003, OR = 4.19, 1.62–10.80), T2D by 3 fold (P = 0.008, OR = 3.23, 1.36–7.60) and T2D + CAD by 3.5 fold (P = 0.029, OR = 3.64, 1.14–11.66). Factor analyses show that BMI, WC, and WHR are core predictors for CAD and T2D, whereas CHO, TG and VLDL for T2D + CAD. The present study concludes that GG genotype of CRP + 1059 G>C polymorphism and clustering of obesity and dyslipidemia underlie the risk towards CAD, T2D and T2D + CAD in the North-West Indian population of Punjab.

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CRP + 1059 G>C SNP analyzed in 266 T2D, 109 T2D with CAD, 206 CAD, and 235 controls

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GG genotype increases the risk towards T2D, CAD, and T2D + CAD in population of Punjab.

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GC genotype provides protection towards T2D, CAD, and T2D + CAD in population of Punjab.

•

Clustering of obesity and dyslipidemia underlies the risk towards T2D, CAD, and T2D + CAD.

The neutrophilic inflammatory phenotype is associated with systemic inflammation in asthma

BACKGROUND

The role of systemic inflammation in asthma is unclear. The aim of this study was to compare systemic inflammation in subjects with stable asthma, categorized by airway inflammatory phenotype, with healthy control subjects.

METHODS

Adults with stable asthma (n = 152) and healthy control subjects (n = 83) underwent hypertonic saline challenge and sputum induction. Differential leukocyte counts were performed on selected sputum. Plasma high-sensitivity C-reactive protein (CRP), IL-6, and tumor necrosis factor-α levels and sputum IL-8 and neutrophil elastase levels were determined by enzyme-linked immunosorbent assay. Sputum IL-8 receptor α (IL-8RA) and IL-8 receptor β (IL-8RB) messenger RNA expression were determined by real-time polymerase chain reaction.

RESULTS

Subjects with asthma were classified as having nonneutrophilic asthma or neutrophilic asthma. The asthma (neutrophilic) group had increased systemic inflammation compared with the asthma (nonneutrophilic) and healthy control groups, with median (interquartile range) CRP levels of 5.0 (1.6-9.2), 1.8 (0.9-5.3), and 1.8 (0.8-4.1) mg/L (P = .011), respectively, and IL-6 levels of 2.1 (1.5-3.1), 1.4 (1.0-2.1), and 1.1 (0.8-1.5) pg/mL (P < .001), respectively. The proportion of subjects with elevated CRP and IL-6 levels was also higher in the asthma (neutrophilic) group. Sputum IL-8 and neutrophil elastase protein and IL-8RA and IL-8RB gene expression were significantly increased in the asthma (neutrophilic) group. In multiple regression analysis of subjects with asthma, sex, BMI, statin use, and percent sputum neutrophils were significant predictors of log(10)CRP. Sex, BMI, and %FEV(1) were significant predictors of log(10)IL-6.

CONCLUSIONS

Systemic inflammation is increased in patients with asthma with neutrophilic airway inflammation and associated with worse clinical outcomes. Systemic inflammation may contribute to the pathophysiology of neutrophilic asthma.

Plasma pyridoxal-5-phosphate is inversely associated with systemic markers of inflammation in a population of U.S. adults

Low vitamin B-6 status, based on plasma concentrations of pyridoxal-5-phosphate (PLP), has been identified in inflammatory diseases, including cardiovascular disease, rheumatoid arthritis, inflammatory bowel disease, and diabetes. Our objective was to examine the association between plasma PLP and multiple markers of inflammation in a community-based cohort [n = 2229 participants (55% women, mean age 61 ± 9 y)]. We created an overall inflammation score (IS) as the sum of standardized values of 13 individual inflammatory markers. Multivariable-adjusted regression analysis was used to assess the associations between the IS and plasma PLP. Geometric mean plasma PLP concentrations were lower in the highest tertile category of IS relative to the lowest (61 vs. 80 nmol/L; P-trend < 0.0001). Similarly, the prevalence of PLP insufficiency was significantly higher for participants in the highest compared with the lowest tertiles for IS categories. These relationships persisted after accounting for vitamin B-6 intake. Also, there were significant inverse relationships between plasma PLP and 4 IS based on functionally related markers, including acute phase reactants, cytokines, adhesion molecules, and oxidative stress. In addition, secondary analyses revealed that many of the individual inflammatory markers were inversely associated with plasma PLP after adjusting for plasma C-reactive protein concentration. This study, in combination with past findings, further supports our hypothesis that inflammation is associated with a functional deficiency of vitamin B-6. We discuss 2 possible roles for PLP in the inflammatory process, including tryptophan metabolism and serine hydroxymethyltransferase activity.

Telomere-associated polymorphisms correlate with cardiovascular disease mortality in Caucasian women: the Cardiovascular Health Study

Leukocyte telomere length (LTL) is linked to cardiovascular disease (CVD); however, it is unclear if LTL has an etiologic role in CVD. To gain insight into the LTL and CVD relationship, a cohort study of CVD mortality and single nucleotide polymorphisms (SNPs) in OBFC1 and TERC, genes related to LTL, was conducted among 3271 Caucasian participants ages ≥65 years enrolled 1989-1990 in the Cardiovascular Health Study. Leukocyte DNA was genotyped for SNPs in OBFC1 (rs4387287 and rs9419958) and TERC (rs3772190) that were previously associated with LTL through genome-wide association studies. Cox regression was used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). The OBFC1 SNPs were in linkage disequilibrium (r(2)=0.99), and both SNPs were similarly associated with CVD mortality in women. For women, there was a decreased risk of CVD death associated with the minor allele (rs4387287), HR=0.7; 95% CI: 0.5-0.9 (CC vs. AC) and HR=0.5; 95% CI: 0.20-1.4 (CC vs. AA) (P-trend <0.01). For men there was no association, HR=1.0; 95% CI: 0.7-1.3 (CC vs. AC) and HR=1.7; 95% CI: 0.8-3.6 (CC vs. AA) (P-trend=0.64). These findings support the hypothesis that telomere biology and associated genes may play a role in CVD-related death, particularly among women.

The relationship between cortisol, C-reactive protein and hypertension in African and Causcasian women: the POWIRS study

Research on the roles that C-reactive protein (CRP) and other risk factors such as cortisol and obesity play in the diagnosis of cardiovascular disease (CVD) in African and Caucasian women has become increasingly imperative when one considers the prevalence of hypertension in these groups. CRP and cortisol have been associated with an increased prevalence of hypertension and obesity. Cortisol has also been linked with both hypertension and the hypothalamic-pituitary-adrenal (HPA) response. African women have previously presented with an increased vascular reactivity. Conversely, Caucasian women have displayed an increased central cardiac reactivity. We included African (n = 102) and Caucasian (n = 115) women in the study, matched for age and body mass index. Elevated CRP levels were observed in African women compared to Caucasian women. A trend of hypocortisolism was exhibited in both hypertensive ethnic groups. Systolic blood pressure (SBP) and a vascular marker, arterial compliance (Cw), predicted hypertension in African women. Conversely, in Caucasian women, only SBP predicted hypertension. These results suggest the apparently diverse roles that dysregulation by the HPA axis, in conjunction with the respective cardiac and vascular responses in both Caucasian and African women, can play in future cardiovascular risk for these groups.

Inflammation and type 2 diabetes

Low-grade inflammation is a common feature in subjects with type 2 diabetes (T2D). Heart disease, the metabolic syndrome and T2D all have in common the increased concentration of circulatory cytokines as a result of inflammation. Inflammatory cytokines are produced by different cell types and secreted into the circulation, where they regulate different tissues through their local, central and peripheral actions. This review focuses on C-reactive protein (CRP), a well-established marker of the development of inflammation, on tumour necrosis factor (TNF)-α, an inflammatory marker strongly associated with diabetes, and on adiponectin, a cytokine produced by adipose tissue and associated with insulin sensitivity. While it is clear from the literature that these cytokines play a major role in the development of T2D or, in the case of adiponectin, its prevention, the best strategy for favourably altering the inflammatory response is still a matter of debate.

Sensitive detection of cardiac biomarker using ZnS nanoparticles as novel signal transducers

C-reactive protein (CRP), a 115 kDa pentameric protein, is one of the important cardiac biomarkers that are indicative of coronary heart events. Sensitive detection of CRP in human serum is critical for the diagnosis of coronary heart disease. This work presents a sensitive sandwich immunoassay for the detection of CRP in human serum using zinc sulfide (ZnS) nanoparticles as novel fluorescence signal transducers. In this assay, monoclonal anti-CRP antibodies are used to capture CRP in human serum, and then the captured CRPs are incubated with biotinylated monoclonal anti-CRP and Neutravidin coated ZnS nanoparticle to form sandwich immunocomplexes. Quantification of CRP occurs when zinc ions released from ZnS nanoparticle labels are mixed with zinc-ion sensitive fluorescence indicator Fluozin-3 for fluorescence generation. The developed assay presents a detection limit around 10 pM and a detection range with more than two orders of magnitude.

Relationship between bilirubin and C-reactive protein

BACKGROUND

Epidemiologic studies have shown that serum total bilirubin is inversely related to an increased risk of coronary artery disease. However, the number of studies which have focused on the relationship between bilirubin and C-reactive protein (CRP), which is a marker reflecting chronic vascular inflammation, are limited.

METHOD

This cross-sectional study consisted of 2307 Korean adults who visited the Center for Health Promotion for a routine health check-up from January 2009 to December 2009.

RESULT

CRP level showed a declining tendency as total bilirubin increased according to total bilirubin quartiles. Negative relations of CRP with both total and direct bilirubin were found after adjustment of age, body mass index, hypertension, diabetes, hypercholesterolemia, cardiovascular disease, taking aspirin, smoking, alcohol drinking and regular exercise and total bilirubin or direct bilirubin.

CONCLUSIONS

This study found that elevation of the two types of bilirubin (total and direct) have a relationship with a low serum CRP level among apparently healthy Korean adults. It is hypothesized that a low serum CRP level may be due to the antioxidant and anti-inflammatory effects of bilirubin metabolism.