C-reactive protein gene polymorphisms and the incidence of post-angioplasty restenosis

C-Reactive Protein Level and the Genetic Variant rs1130864 in the CRP Gene as Prognostic Factors for 10-Year Cardiovascular Outcome

BACKGROUND

Cardiovascular disease (CVD) is the primary cause of premature death and disability worldwide. There is extensive evidence that inflammation represents an important pathogenetic mechanism in the development and prognosis of CVD. C-reactive protein (CRP) is a potential marker of vascular inflammation and plays a direct role in CVD by promoting vascular inflammation. The objective of this study (ClinTrials.gov identifier: NCT01045070) was to assess the prognostic impact of CRP protein levels and genetic variants of CRP gene events on cardiovascular (CV) outcome (10-year follow-up) in patients suffering from CVD.

METHODS

CVD patients were prospectively included in this study (n = 1002) and followed up (10 years) regarding combined CV endpoint (CV death, death from stroke, myocardial infarction (MI), and stroke/transient ischemic attack (TIA)). CRP protein level (particle-enhanced immunological turbidity test) and genetic variants (rs1130864, rs1417938, rs1800947, rs3093077; polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) after DNA extraction from EDTA-blood) were evaluated.

RESULTS

In survival analyses, increased CRP protein levels of ≥5 mg/L (log-rank test: p < 0.001, Cox regression: p = 0.002, hazard ratio = 1.49) and CT + TT genotype of rs1130864 (log-rank test: p = 0.041; Cox regression: p = 0.103, hazard ratio = 1.21) were associated with a weaker CV prognosis considering combined CV endpoint.

CONCLUSIONS

Elevated CRP level and genetic variant (rs1130864) were proven to provide prognostic value for adverse outcome in CVD patients within the 10-year follow-up period.

The Relationship between VEGFA and TGFB1 Polymorphisms and Target Lesion Revascularization after Elective Percutaneous Coronary Intervention

Background and Aim

The specific association between genetic variation and in-stent restenosis is still only partly understood. The aim of this study is to analyze the relationship between functional polymorphisms in the genes encoding vascular endothelial growth factor A (VEGF-A; rs699947) and transforming growth factor beta 1 (TGF-β1; rs1800470) and target lesion revascularization (TLR) risk.

Methods

A total of 676 patients (805 lesions) with stable coronary artery disease (SCAD) who received elective percutaneous coronary intervention (PCI) with at least one bare-metal stent implantation were included. The primary study endpoint was TLR at a 4-year follow-up.

Results

The TLR rate was higher in patients with the VEGFA A/A genotype (15.4%) than in patients with the VEGFA A/C (7.9%) and C/C (8.9%) genotypes (p = 0.009). The VEGFA A/A genotype, after adjustment for clinical and procedural covariates, remained significantly and independently associated with the TLR (hazard ratio—2.09 [95% confidence interval 1.32–3.33, p = 0.0017]). However, we found no association between TLR and the TGFB1 genotype.

Conclusion

The VEGFA A/A genotype is significantly and independently associated with TLR risk in Polish SCAD patients who received elective PCI with bare-metal stent implantation.

C-reactive protein levels and genetic variants of CRP as prognostic markers for combined cardiovascular endpoint (cardiovascular death, death from stroke, myocardial infarction, and stroke/TIA)

BACKGROUND

The aim of this analysis was to evaluate the importance of C-reactive protein levels and genetic variants of CRP as prognostic markers for further cardiovascular (CV) events (3-year follow-up) in a cohort of in-patients with cardiovascular disease (CVD) patients.

METHODS AND RESULTS

Patients with angiographic proven CVD (n=939) were prospectively included. The three-year CV outcome of the patients was evaluated considering the predefined, combined endpoint (CV death, death from stroke, myocardial infarction, and stroke/TIA). Polymorphisms rs1800947, rs1417938, rs1130864, rs3093077 were analysed. In Kaplan-Meier survival curve and Cox regression increased CRP levels of ⩾5mg/l (log-rank test: p=0.001, Cox regression: hazard ratio=1.77, 95% CI: 1.2-2.7) and the GG genotype of rs1800947 (log-rank test: p=0.01, Cox regression: hazard ratio=1.99, 95% CI: 1.1-3.6) were associated with the incidence of the combined endpoint.

CONCLUSIONS

Both a CRP level ⩾5mg/l and SNP rs1800947 of the CRP gene were independent risk factors for further adverse CV events among patients with CVD within three years follow-up.

A novel haplotype within C-reactive protein gene influences CRP levels and coronary heart disease risk in Northwest Indians

According to several epidemiological and clinical studies, the concentration of C-reactive protein (CRP) in blood is associated with the risk of coronary heart disease (CHD). However, these studies are limited in high incidence and prevalence area of North-West India. The present case control study investigated the contribution of three relevant CRP single nucleotide polymorphisms: -717A>G located in the promoter region (rs2794521), +1059G>C on exon2 (rs1800947) and +1444C>T in the 3' UTR (rs1130864) in 180 angiographically verified CHD cases and 175 control subjects. Minor allele frequencies (G, C and T) of rs2794521, rs1800947 and rs1130864 are observed to be 21.1, 11.7, 29.4 and 11.4, 10.0, 19.7 % in CHD cases and controls respectively. AA genotype of -717A>G and TT genotype of +1444C>T were significantly associated (P = 0.02 & 0.03 respectively) with the risk of CHD whereas, +1059G and +1444T were found to be strongly related (P = 0.023 & P = 0.008 respectively) with multivariable adjusted CRP levels. AGT Haplotype was significantly associated with the adjusted CRP levels (P < 0.05). Disease association analysis revealed that haplotype AGT influences CHD risk (OR 2.4, 95 % CI 1.23-4.84, P = 0.006) which exacerbates after correcting the confounding effects of risk variables (OR 2.5, 95 % CI 1.27-4.99, P = 0.004). With the global index of Akaike information criterion, it has been observed that the carrying each single unit of this susceptibility haplotype increases CHD risk by a value of 2.41 ± 0.439 (β ± SE) in the recessive mode.

Human C-reactive protein gene polymorphism and metabolic syndrome are associated with premature coronary artery disease

The aim of this study was to investigate the association between C-reactive protein (CRP) gene polymorphism and metabolic syndrome (MetS) with premature coronary artery disease (PCAD). 116 patients with PCAD (58 with MetS and 58 without MetS) and 119 controls were included in the study. CRP gene +1059 G>C polymorphism was analyzed by polymerase chain reaction. Serum hs-CRP was measured using high-sensitivity enzyme-linked immunosorbent assay. Carriers of C allele of the CRP +1059 G>C polymorphism had 3.37 fold increased risk to develop MetS in patients with PCAD. In addition CRP gene and hs-CRP levels were independent risk factors for PCAD and MetS. The present study provides new evidence that the presence of CRP +1059 G>C polymorphism and hs-CRP levels are independent determinants of PCAD and MetS in Egyptians. The results of our study suggest a synergistic effect of CRP C allele with classical risk factors such as hypertension, obesity, dyslipidemia and MetS.

A functional variant in the promoter region regulates the C-reactive protein gene and is a potential candidate for increased risk of atrial fibrillation

OBJECTIVES

In a large population-based cohort, the level of C-reactive protein (CRP) in patients at baseline predicts an increased risk of future development of atrial fibrillation (AF). The mechanism of this increased risk is unknown. Furthermore, both the molecular effects of CRP on atrial myocytes and fibroblasts and whether genetic variants in the CRP gene predispose to AF are also unknown.

METHODS

A genetic association study between CRP gene polymorphisms and AF was performed in two independent populations (I: 100 AF patients and 101 controls; II: 348 AF patients and 356 controls), with functional studies to elucidate the mechanism of association.

RESULTS

Three polymorphisms (T-861C, A-821G and C-390A/C-390T) were found in the 1-kb promoter of CRP. A triallelic polymorphism (C-390A/C-390T) captured all haplotype information and determined the CRP gene promoter activity and the plasma CRP level, and was in nearly complete linkage disequilibrium with G1059C polymorphism in exon 2. The -390A variant was associated with a higher CRP gene promoter activity, a higher plasma CRP level and a higher risk of AF. Patients with AF also had a higher plasma CRP level than controls. CRP significantly increased the inward L-type calcium current in atrial myocytes with no changes in other ionic currents. CRP did not affect the expressions of type I alpha 1 (COL1A1), type III alpha 1 (COL3A1) and type 1 alpha 2 (COL1A2) procollagens in atrial fibroblasts.

CONCLUSION

A CRP gene promoter triallelic polymorphism was associated with CRP gene promoter activity, determined the plasma level of CRP, and predicted the risk of AF. The mechanism of this may be via augmention of calcium influx by CRP in atrial myocytes, but not because of atrial fibrosis.

The evolving role of inflammatory biomarkers in risk assessment after stent implantation

The main adverse reactions to coronary stents are in-stent restenosis (ISR) and stent thrombosis. Along with procedural factors, individual susceptibility to these events plays an important role. In particular, inflammatory status, as assessed by C-reactive protein levels, predicts the risk of ISR after bare-metal stent implantation, although it does not predict the risk of stent thrombosis. Conversely, C-reactive protein levels fail to predict the risk of ISR after drug-eluting stent (DES) implantation, although they appear to predict the risk of stent thrombosis. Of note, DES have abated ISR rates occurring in the classical 1-year window, but new concern is emerging regarding late restenosis and thrombosis. The pathogenesis of these late events seems to be related to delayed healing and allergic reactions to polymers, a process in which eosinophils seem to play an important role by enhancing restenosis and thrombosis. The identification of high-risk individuals based on biomarker assessment may be important for the management of patients receiving stent implantation. In this report, we review the evolving role of inflammatory biomarkers in predicting the risk of ISR and stent thrombosis.

C-reactive protein gene polymorphisms affect plasma CRP and homocysteine concentrations in subjects with and without angiographically confirmed coronary artery disease

Human C-reactive protein (CRP) is a reactant involved in the acute phase response and one of the many molecular factors involved in pathogenesis of coronary artery disease (CAD). CRP gene variants potentially mediate CRP plasma concentrations and the development of CAD. 220 Croatian subjects with angiographically confirmed CAD and 132 control subjects were included in the study. CRP gene polymorphisms 1059G/C and -717G/A were determined by RFLPs, using MaeIII and KspI endonuclease, respectively. Plasma concentrations of CRP and homocysteine were determined by immunoturbidimetry and FPIA, respectively. CRP 1059G/C gene variants were significantly associated with CAD (OR = 0.50; 95% CI = 0.27, 0.94; P = 0.032). Wild GG genotype and rare allele C carrier genotypes were 184 and 22 in CAD(+) group, and 101 and 24 in CAD(-) group, respectively. Multivariate analysis with age, gender, BMI, smoking status, hypertension and diabetes as covariates showed that 1059C carriers had lower CRP concentrations in CAD(-) (P = 0.010) and CAD(+) subjects (P = 0.028). This allele was also significantly associated with lower plasma homocysteine concentrations in both groups (P = 0.018 for CAD(-) and 0.002 for CAD(+). There was no significant difference between CAD(+) and CAD(-) subjects in absolute frequencies for CRP -717A/G gene variant, but multivariate analysis showed that carriers of the rarer G allele had significantly higher CRP plasma concentrations in CAD(-) subjects (P = 0.031) and higher homocysteine concentrations in CAD(+) group (P < 0.001). Atherosclerosis is an inflammatory disease resulting from different genetic and environmental factors. Results presented here support the contribution of CRP genetic variations in the development of CAD.

C-Reactive Protein Gene Polymorphisms, C-Reactive Protein Blood Levels, and Cardiovascular Disease Risk

C-reactive protein (CRP), a blood marker of inflammation and a hallmark of the acute-phase response, has been shown to be a powerful and specific predictor of cardiovascular event risk in populations of otherwise healthy persons. Here we review what is known about CRP gene polymorphisms, discuss how these might affect the epidemiology of CRP and our understanding of CRP's contribution to cardiovascular disease, and examine their potential clinical usefulness. Evidence shows that certain subtle variations in the CRP gene sequence, mostly single nucleotide polymorphisms, predictably and strongly influence the blood level of CRP. Some of these variations are associated with clinical correlates of cardiovascular disease. If future studies can establish with certainty that CRP influences cardiovascular biology, then CRP gene profiling could have clinical utility.

Human C-reactive protein (CRP) gene 1059G>C polymorphism is associated with plasma CRP concentration in patients receiving coronary angiography

BACKGROUND/PURPOSE

Elevation of C-reactive protein (CRP) level is associated with increased risk of cardiovascular events. The 1059 G>C polymorphism in exon 2 of the CRP gene has been shown to affect plasma concentration of CRP. We want to elucidate the effect of this polymorphism on the development of coronary artery disease (CAD) among the Chinese population in Taiwan.

METHODS

We scrutinized 536 patients undergoing coronary angiography (365 patients with CAD and 171 controls with patent coronaries) and evaluated the association of CRP gene 1059 G>C polymorphism with CAD. Genotyping of the polymorphism was performed by polymerase chain reaction and MaeIII restriction enzyme digestion.

RESULTS

The CC genotype was associated with lower plasma CRP concentration (GG, 6.5+/-5.8; GC, 3.3+/-4.4; CC, 2.3+/-3.1 mg/L; p=0.02). Subjects with CAD or myocardial infarction (MI) had significantly higher plasma CRP concentration than that in controls (CAD vs. controls, 8.9+/-18.9 vs. 3.3+/-7.2 mg/L; p<0.001), while patients with MI showed higher CRP when compared to those with chronic stable angina (13.5+/-22.9 vs. 5.2+/-14.1 mg/L; p<0.001). However, this polymorphism was not associated with CAD in our population.

CONCLUSION

Our data suggest that human CRP gene 1059 G>C polymorphism is associated with plasma CRP concentration among Chinese in Taiwan receiving coronary angiography.

Triggered C-reactive protein (CRP) concentrations and the CRP gene −717A>G polymorphism in acute stroke or transient ischemic attack

C-reactive protein (CRP) increases following an acute stroke/transient ischemic attack (TIA), but the increment level varies among patients. We analyzed CRP concentrations during an acute stroke/TIA in relation to the CRP gene -717A>G polymorphism. Six months following an acute ischemic stroke/TIA, basal concentrations of CRP were measured in 507 controls and 219 patients and were found to be unassociated with the CRP -717A>G polymorphism. However, during the acute phase of stroke/TIA, individuals with the AG/GG genotype had significantly elevated CRP concentrations as opposed to those with the AA genotype (2.02 +/- 1.59 vs. 1.73 +/- 1.69 mg/l, P = 0.027). In addition, significant 3.22-fold increments in CRP concentrations was noted in individuals carrying the -717G allele when comparing the acute phase with the basal state of each patient and averaging the results. CRP -717A>G polymorphism is associated with triggered CRP concentrations during acute stroke/TIA. These findings might shed more light on the mechanisms of CRP elevation in acute ischemic stroke/TIA.

C-Reactive protein haplotype predicts serum C-reactive protein levels but not cardiovascular disease risk in a dialysis cohort

BACKGROUND

C-Reactive protein (CRP) gene variation has been associated with serum CRP levels in the general population. We examined the associations of CRP gene variation with longitudinal CRP measurements and incident cardiovascular disease (CVD) risk in a cohort of 504 white and 244 African-American incident dialysis patients.

METHODS

Seven tagging single-nucleotide polymorphisms in the CRP gene were selected by using the Carlson method (r(2) > 0.65). High-sensitivity CRP was measured every 6 months (mean, 4.6 months). Haplo.glm was used to determine the association of haplotypes with serum CRP levels and CVD risk. Global tests from Haplo.score were conducted to determine statistical significance.

RESULTS

Compared with the most common haplotype, 1 haplotype was associated with a 52% lower CRP level at baseline among African Americans (ratio, 0.48; 95% confidence interval [CI], 0.28 to 0.82; global P-value = 0.0005). Furthermore, this haplotype was associated significantly with lower serum CRP levels during 36 months of follow-up. Among whites, this haplotype was associated with an 18% (ratio, 0.82; 95% CI, 0.56 to 1.22; n = 6 carriers) lower CRP level compared with the most common haplotype with a frequency of 1% (global P-value = 0.048). No association was detected between CRP gene variation and CVD risk in either whites or African Americans.

CONCLUSION

Compared with the most common haplotype of the CRP gene, 1 haplotype predicts a lower serum CRP level over time, but no association exists between haplotype of CRP gene and incident CVD in this incident dialysis population. Serum CRP level might be a biomarker, rather than a causal factor, in CVD development. CRP variation may lead to susceptibility to inflammation, but not risk for CVD; however, replication in multiple settings is necessary.

C-reactive protein 3′ UTR +1444C>T polymorphism in patients with spontaneous venous thromboembolism

OBJECTIVE

Data on C-reactive protein (CRP) as a risk indicator of venous thromboembolism are conflicting. A recent study reported higher CRP levels in homozygous carriers of a novel CRP gene polymorphism at the 3' UTR (CRP +1444C>T). We investigated, whether homozygosity for CRP +1444C>T is associated with an increased risk of spontaneous venous thromboembolism (VTE).

METHODS AND RESULTS

CRP +1444C>T genotype and plasma levels were assessed in 128 patients with deep venous thrombosis (DVT, 70 females/58 males), 105 with pulmonary embolism (PE, 58 females/47 males) and 122 healthy individuals (60 females/62 males). CRP +1444TT was significantly associated with increased CRP plasma levels in healthy individuals. CRP +1444TT was more frequent (14%) among controls than DVT patients (9%, p=0.26) or PE patients (6%, p=0.05), respectively. No significant deviation from Hardy-Weinberg equilibrium was observed in patients (p=0.8) or controls (p=0.3), respectively. CRP +1444C>T was not significantly associated with CRP levels in patients with VTE.

CONCLUSIONS

Homozygous carriers of the CRP 3' UTR +1444C>T polymorphism do not have a significantly increased risk of VTE. Our data support the assumption that a clinically relevant association between CRP and VTE is missing.

C-reactive protein gene haplotypes and risk of coronary heart disease: the Rotterdam Study

AIMS

C-reactive protein is associated with risk of cardiovascular disease. However, whether C-reactive protein is a marker of severity of cardiovascular disease or actually is involved in its pathogenesis remains unknown. We investigated the relation between C-reactive protein haplotypes, representing the comprehensive variation of the C-reactive protein gene, and coronary heart disease.

METHODS AND RESULTS

The Rotterdam Study is a prospective population-based study among men and women aged 55 years and older. C-reactive protein was associated with risk of coronary heart disease, with a multivariable adjusted hazard ratio of 1.9 (95% CI 1.5-2.4) for the highest vs. the lowest quartile. Four C-reactive protein haplotypes were present with overall frequencies of 32.8, 31.7, 29.5, and 5.9%. C-reactive protein serum levels were significantly different according to C-reactive protein haplotypes. C-reactive protein haplotypes were not associated with coronary heart disease.

CONCLUSION

Steady-state C-reactive protein serum level is influenced by C-reactive protein gene haplotypes. Although elevated C-reactive protein level has lately been found to be a consistent and relatively strong risk factor for cardiovascular disease, our study does not support that the common variation in the C-reactive protein gene has a large effect on the occurrence of coronary heart disease.

Present status of outcome prediction of invasive coronary treatment by using genetic markers

A growing number of studies suggest that the outcome after invasive coronary treatment may be in part genetically determined. Here, we review the present status of outcome prediction of invasive coronary treatments by using genetic markers. Although some studies found an association between one or another genetic marker with one or another clinical endpoint, many other studies found no such relations; to date, none of the genetic markers that have been investigated in association studies are used in routine clinical practice to prospectively assess the prognosis following invasive coronary treatment or to decide upon therapeutic strategies. Many associations between genetic markers and certain clinical endpoints were initially reported in small studies but could not be confirmed in larger ones. Some of these discrepancies may be explained by publication bias. Some genetic variants may have true effects on clinical endpoints, which, albeit biologically interesting, do not bear much clinical relevance. On the other hand, many-if not most-studies that have been published to date are more or less grossly underpowered and very rarely report on the results of an a priori power analysis. Thus, there is still a need for further high-quality studies designed to investigate the specific contribution of genetic factors to the outcome after invasive coronary interventions.

Predictive role of hs-C-reactive protein in patients with antiphospholipid syndrome

High-sensitive C-reactive protein (hs-CRP) is a marker of inflammation which has been shown in several prospective studies to independently predict myocardial infarction, stroke and peripheral artery disease. Patients with antiphospholipid antibodies (aPL) are at increased risk of recurrent thromboembolic events, but the possibility of predicting this risk seems rather limited. Similarities were recently found between aPL and CRP in the pathology of thrombosis. The current study investigated the predictive role of hs-CRP in a cohort of patients with neurological manifestations. A follow-up investigation was done in a cohort of 55 aPL-positive patients with acute manifestations of neurological disease. hs-CRP levels were measured in all patients at enrollment and were compared to the patients' condition after a median period of 32 months. Lupus anticoagulants were detected according to the Standardization of Lupus Anticoagulants (SSC) of the ISTH. Anticardiolipin tests were performed by a beta2-glycoprotein I-dependent enzyme-linked immunsorbent assay (Pharmacia ELISA). hs-CRP was measured by latex-enhanced turbidometry (dimension RXL, Dade Behring). Cerebral infarctions and transient ischemic attacks were the most frequent cerebral events. In patients with aPL, elevated levels of hs-CRP were closely associated with an increased rate of recurrent or residual symptoms (OR, 12.5; 95% CI, 3.72-41.94) and were not related to other risk factors, except smoking (p<0.05). The rate at which a given patient's condition deteriorated was also related to the level of hs-CRP. In patients with antiphospholipid syndrome (APS), elevated levels of hs-CRP may identify a group of patients which is at high risk of recurrent or residual neurological symptoms and which may benefit from more careful follow-up and from antithrombotic therapy.

Gene Polymorphism Association Studies in Dialysis: The Nutrition-Inflammation Axis

Although traditional risk factors for cardiovascular disease are common in dialysis patients, they alone cannot explain the unacceptably high prevalence of vascular disease in this patient group. Much recent interest has therefore focused on the role of various nontraditional cardiovascular risk factors, such as inflammation, wasting, obesity, vascular calcification, and oxidative stress. In addition, genetic factors such as single nucleotide polymorphisms (SNPs) may significantly influence the immune response, the levels of inflammatory markers and body composition, as well as the prevalence of vascular calcification in this patient group. While genetic variations in the tumor necrosis factor (TNF)-alpha-308 and interleukin (IL)-10 -1082 SNPs seem to be consistently associated with adverse clinical outcome in end-stage renal disease (ESRD) patients, the results regarding genetic variations in the IL-6 gene have been conflicting. To elucidate the respective role of DNA polymorphisms in the IL-6 and C-reactive protein (CRP) genes, as well as genes that encode vascular calcification inhibitors (such as fetuin-A, matrix Gla protein, and osteoprotegerin), sufficiently powered studies are needed in which both the protein product and the specific phenotype are determined. In addition, polymorphisms in genes related to body composition may be excellent candidates for analysis in the ESRD population, since nutritional parameters are strongly associated with adverse events in these patients. It seems conceivable that in the future, prognostic or predictive multigene DNA assays (which allow a simultaneous and rapid assessment of multiple genetic variants) will provide nephrologists with a more precise approach for the identification of "high-risk" ESRD patients and the development of accurate individualized treatment strategies.