Admission C-reactive protein levels and 30-day mortality in patients with acute myocardial infarction

Predictive value of white blood cell subtypes for long-term outcome following myocardial infarction

INTRODUCTION

Elevation of total white blood cells (WBC) count is associated with higher mortality in patients with acute coronary syndromes. However, it is unknown which specific subset of leukocytes best correlates with increased risk of adverse outcome.

METHODS AND RESULTS

We prospectively studied the predictive value of WBC subtypes for long-term outcome in 1037 patients with acute myocardial infarction (AMI). Total WBC, neutrophil, monocyte and lymphocyte counts, and high-sensitivity C-reactive protein (CRP) were obtained in each patient. The median duration of follow up was 23 months (range, 6-42 months). Analyzed separately, baseline total WBC (HR 2.2, 95% CI 1.5-3.3; P<0.0001), neutrophil (HR 2.7, 95% CI 1.8-4.1; P<0.0001) and monocyte (HR 1.9, 95% CI 1.3-2.8; P=0.001) counts in the upper quartile, and lymphocyte count in the lower quartile (HR 1.5, 95% CI 1.1-2.3; P=0.03), were all independent predictors of mortality. Comparing nested models, adding other WBC data failed to improve model based on neutrophil count. In contrast, adding neutrophil count to the models based on total WBC (P=0.01), on monocyte count (P<0.0001) or on lymphocyte count (P<0.0001) improved the prediction of the models. Neutrophil count in the upper quartile (>or=9800 microL(-1)) remained a strong independent predictor of mortality after adjustment for left ventricular systolic function and for CRP (HR 2.2, 95% CI 1.6-3.0; P<0.0001).

CONCLUSION

Of all WBC subtypes, elevated neutrophil count best correlates with mortality in patients with AMI. Neutrophil count provides additive prognostic information when combined with CRP.

The impact of hs C-reactive protein and other inflammatory biomarkers on long-term cardiovascular mortality in patients with acute coronary syndromes

We evaluated whether high circulating levels of serum amyloid A (SAA), fibrinogen, interleukin-6 (IL-6) or leukocytes count (LC), can provide any additional predictive value over that provided by hs C-reactive protein (hs-CRP) for the incidence of 5-year cardiovascular mortality, in 458 and 476 consecutive patients with ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation acute coronary syndromes (NSTE-ACS), respectively. By 5 years the incidence of cardiovascular mortality was 37.3% and 35.5% in patients with STEMI and NSTE-ACS, respectively. Each of the study inflammatory biomarkers conferred independent to clinical risk predictors (and to cardiac troponin I) long-term prognostic information (all p<0.05), but only LC provided additional predictive value over that provided by hs-CRP, in either cohort (p<0.05). By multivariate Cox regression analysis, hs-CRP (p<0.001 for both cohorts) and LC (p=0.009 and p<0.001 for STEMI and NSTE-ACS, respectively) were the only inflammatory biomarkers independently associated with the incidence of 5-year cardiovascular mortality. According to the present results high circulating levels of LC but not of SAA, fibrinogen or IL-6 can provide additional long-term predictive value over that provided by hs-CRP in patients with acute coronary syndromes.

Relation of C-reactive protein and new-onset atrial fibrillation in patients with acute myocardial infarction

Recent studies have implicated systemic inflammation in the genesis and maintenance of atrial fibrillation (AF). A robust inflammatory response is an integral component of the response to tissue injury during acute myocardial infarction (AMI). However, there is no information concerning the association between inflammation and AF in patients with AMI. We studied 1,209 patients admitted for AMI. C-reactive protein (CRP) was measured by a high-sensitivity assay within 12 to 24 hours after symptom onset. The relation between CRP and new-onset AF occurring during the hospital course and at 1 year was analyzed using multivariable logistic regression and Cox models, respectively. New-onset AF during hospitalization occurred in 6.5%, 10.4%, and 17.1% of patients in the first, second and third CRP tertiles, respectively (p trend <0.0001). In a multivariable logistic regression, adjusting for clinical variables and ejection fraction, compared with patients in the first CRP tertile, the odds ratios for AF were 1.5 (95% confidence interval 0.9 to 2.5, p = 0.15) and 2.0 (95% confidence interval 1.2 to 3.3, p = 0.008) in patients in the second and third CRP tertiles, respectively (p for trend = 0.007). In a Cox multivariate analysis, CRP remained an independent predictor of new-onset AF at 1 year. In conclusion, in a large cohort of patients with AMI, there was a graded positive association between increased CRP and new-onset AF. Inflammation may contribute to the development of AF in the setting of AMI.

C-reactive protein and heart failure after myocardial infarction in the community

BACKGROUND

There is a paucity of data on the prognostic role of C-reactive protein (CRP) measured after myocardial infarction. We prospectively examined the association of CRP with heart failure and death among patients with myocardial infarction in the community.

METHODS AND RESULTS

All Olmsted County residents who had a myocardial infarction meeting standardized criteria were prospectively enrolled to measure CRP on admission and followed for heart failure and death. A total of 329 consecutive patients (mean age 69 +/- 16 years, 52% men) were enrolled. At 1 year, 28% of patients experienced heart failure and 20% died. There was a strong positive graded association between CRP and the risk of developing heart failure, as well as dying over the period of follow-up (P < .001). Compared with patients in the first tertile, patients in the third tertile of the CRP distribution had a markedly increased risk of heart failure and death independently of age, sex, troponin T, Q wave, comorbidity, previous myocardial infarction, and recurrent ischemic events (adjusted hazard ratio 2.47 [95% confidence interval, 1.27-4.82] for heart failure and 3.96 [95% confidence interval, 1.78-8.83] for death).

CONCLUSIONS

These prospective data indicate that among contemporary community subjects with myocardial infarction, heart failure and death remain frequent complications. CRP is associated with a large increase in the risk of heart failure and death, independently of age, sex, myocardial infarction severity, comorbidity, previous myocardial infarction, and recurrent ischemic events. These data suggest that inflammatory processes may play a role in the development of heart failure and death after myocardial infarction independently of other conventional prognostic indicators.

Level and Value of Interleukin-18 in Patients With Acute Myocardial Infarction Undergoing Primary Coronary Angioplasty

BACKGROUND

The prognostic value of interleukin (IL)-18 in patients with ST-segment elevation acute myocardial infarction (STEMI) is currently unclear. Thus, the purpose of this study was to test whether the circulating IL-18 level can predict prognosis in patients with STEMI undergoing primary percutaneous coronary intervention (PCI).

METHODS AND RESULTS

A prospective cohort study was conducted with 267 consecutive patients with STEMI of onset <12 h who were undergoing primary PCI. Blood samples for plasma IL-18 level were collected in the catheterization laboratory following vascular puncture. The plasma IL-18 level was also evaluated in 25 healthy and 30 at-risk control subjects. The plasma level of IL-18 was significantly higher in acute myocardial infarction (AMI) patients than in both groups of control subjects (all p<0.0001). Patients with high plasma IL-18 level (> or =560 pg/ml) had significantly higher peak creatine kinase-MB levels, higher incidence of cardiogenic shock upon presentation, significantly lower left ventricular ejection fraction (LVEF), lower successful reperfusion and significantly higher incidence of 30-day composite major adverse clinical events (MACE) (advanced congestive heart failure > or = class 3 or 30-day mortality) than those patients with low plasma IL-18 level (<560 pg/ml) (all p<0.0001). Multiple stepwise logistic regression analysis demonstrated that high plasma IL-18 level (> or =560 pg/ml) along with low LVEF (<50%) and cardiogenic shock were the most independent predictors of 30-day MACE (p<0.0001).

CONCLUSIONS

In patients with STEMI, plasma IL-18 level is a major independent inflammatory predictor of 30-day MACE. Evaluation of circulating IL-18 might improve the prediction of unfavorable clinical outcomes following AMI.

Prognostic value of C-reactive protein and cardiac troponin I in primary percutaneous interventions for ST-elevation myocardial infarction

BACKGROUND

The rise in cardiac troponin I after ST-elevation myocardial infarction treated by primary percutaneous coronary interventions (PCIs) is predictive of infarct size and left ventricular ejection fraction (LVEF). However, the comparative value of C-reactive protein (CRP) and troponin I for infarct size evaluation and the respective relationships between these biomarkers and mortality have not been investigated.

METHODS

We studied 87 patients who underwent primary PCI for ST-elevation myocardial infarction. Concentrations of troponin I and CRP were measured before and for 72 hours after PCI. Infarct size was measured by the cumulative release of alpha-hydroxybutyrate deshydrogenase during the 72 hours after PCI (QHBDH72) and by delayed radionuclide LVEF (at 4.6 +/- 1.7 weeks).

RESULTS

Concentrations of CRP at peak and at 24, 48 and 72 hours, and of troponin I at 6 and 72 hours, correlated with QHBDH72 and LVEF. In single variable analysis, at a mean follow-up of 42 +/- 8 months, Killip score of 3 to 4, CRP at baseline and at 48 hours, and troponin I at 6 and 72 hours were related to mortality. By multiple variable analysis, Killip score (OR 9.9, CI 1.6-58.8) and troponin I at 72 hours (OR 9.43, CI 2.1-43.5) were the only independent predictors of mortality.

CONCLUSIONS

Plasma concentrations of CRP and troponin I after PCI were related to infarct size and mortality. However, Killip class and troponin I at 72 hours were the only independent predictors of mortality at long-term follow-up.

Early and late determinants of C-reactive protein release in patients with acute coronary syndrome

Increased levels of C-reactive protein (CRP) could be detected in subjects with acute coronary syndrome (ACS). Several factors, atherosclerosis, coronary flow impairment, myocardial necrosis, each one acting during a different, earlier or later, phase of ACS, are supposed to be involved in CRP release in case of ACS. Role and relevance of each factor, not mutually exclusive, still need to be comparatively evaluated but a cooperative synergism could be presumably hypothesized.

C-reactive protein and cardiovascular disease: weighing the evidence

C-reactive protein (CRP) has been widely promoted as a strong, independent predictor of cardiovascular events and metabolic syndrome, both in general populations and in patients with clinical cardiovascular disease, and as a causal player in atherothrombosis. However, recent evidence shows that the association of CRP with cardiovascular events is weaker than previously thought, that it may be largely attributed to confounding by established causal risk factors, and that CRP is, therefore, probably not a clinically useful risk predictor. The lack of association of noncoding CRP gene polymorphisms (which determine different baseline CRP values) with coronary events or metabolic syndrome does not support a causal role for CRP, and most of the putatively proatherothrombotic in vitro effects claimed for CRP were caused by contaminants in commercial CRP preparations and not by CRP. Future clinical trials of specific CRP inhibitors now in development could directly test the contribution of CRP to pathogenesis of cardiovascular disease.

C-Reactive Protein Induces Matrix Metalloproteinase-1 and -10 in Human Endothelial Cells

OBJECTIVES

We examined the effect of C-reactive protein (CRP) on matrix metalloproteinase (MMP) and inhibitor expression in endothelial cells and in patients with clinical and subclinical atherosclerosis.

BACKGROUND

In addition to predicting atherosclerotic vascular disease, CRP may directly promote a proinflammatory/proatherosclerotic phenotype.

METHODS

Human umbilical vein endothelial cells (HUVECs) and aortic endothelial cells (HAECs) were incubated in the presence or absence of CRP (50 mug/ml). Microarray analysis, real-time polymerase chain reaction, immunological and activity assays for MMPs were performed. Specific inhibitors of mitogen-activated protein kinase pathway were used. The MMP-1 and -10 plasma levels were measured in apparently healthy subjects (n = 70). Immunolocalization of CRP, MMP-1, and MMP-10 was performed in human mammary arteries and carotid endarterectomy specimens.

RESULTS

C-reactive protein augmented MMP-1 and -10 messenger ribonucleic acid expression in HUVEC (p < 0.05) and HAEC (p < 0.01). C-reactive protein stimulation also increased MMP-1 and -10 protein in conditioned culture medium (p < 0.001), as well as MMP activity (p = 0.001). Specific inhibition of p38 or MEK abolished the CRP induction of the MMP-1, whereas MMP-10 induction blockade required the simultaneous inhibition of p38 and Jun N-terminal kinase pathways. Subjects with CRP values >3 mg/l (n = 37) had increased plasma MMP-1 and -10 (p < 0.05), the association being significant after adjustment for confounding variables (p = 0.04 and p = 0.008, respectively). The MMP-10 levels were elevated in subjects with higher carotid intima-media thickness (p = 0.009). Increased CRP and MMP-10 colocalized in endothelial layer and macrophage-rich areas in advanced atherosclerotic plaques.

CONCLUSIONS

Increased local and systemic CRP-related MMP activation might provide a link between inflammation and plaque vulnerability.

Endocrine markers of severity and prognosis in critical illness

The cellular processes that unfold in critical illness involve a variety of circulating substances, that may provide clinically relevant insight into the severity and outcome. Among hormonal markers, cortisol, several thyroid-related substances, as well as natriuretic peptides are discussed in this review. Glucose and lipids constitute metabolic markers, the identification and treatment of the former has been of particular importance. Among immune markers, both proinflammatory and anti-inflammatory cytokines, such as interleukin-6, contribute essential prognostic information. Finally, the complement and coagulation pathways also provide unique insight into this complex and heterogeneous process.

Early Inflammation and Risk of Long-Term Development of Heart Failure and Mortality in Survivors of Acute Myocardial Infarction

OBJECTIVES

We aimed to study the relationship between C-reactive-protein (CRP), obtained within 12 to 24 h of symptoms onset, and long-term risk of death and heart failure (HF) in survivors of acute myocardial infarction (MI).

BACKGROUND

A robust inflammatory response is an integral component of the response to tissue injury during MI. The magnitude of the early inflammatory response to ischemic injury might be an important determinant of long-term outcome.

METHODS

We prospectively studied 1,044 patients admitted with acute MI and discharged from hospital in stable condition.

RESULTS

During a median follow-up of 23 months (range, 6 to 42 months), 113 patients died and 112 developed HF. In a multivariable Cox regression model adjusting for clinical variables and predischarge ejection fraction, compared with patients in the first CRP quartile, the adjusted hazard ratios (HRs) for death progressively increased with higher quartiles of CRP (second quartile 1.4 [95% confidence interval (CI) 0.6 to 2.9]; third quartile 2.3 [95% CI 1.2 to 4.6]; fourth quartile 3.0 [95% CI 1.5 to 5.7]; for trend, p = 0.0002). Compared with patients in the first CRP quartile, the adjusted HRs for HF were: second quartile, 1.1 (95% CI 0.5 to 2.3); third quartile, 1.9 (95% CI 1.0 to 3.6); and fourth quartile, 2.1 (95% CI 1.2 to 3.9) (for trend, p = 0.005).

CONCLUSIONS

C-reactive-protein is a marker of long-term development of HF and mortality in patients with acute MI and provides prognostic information beyond that provided by conventional risk factors and the degree of left ventricular systolic dysfunction.

What does minor elevation of C-reactive protein signify?

Reports of the predictive value of minor elevation of serum C-reactive protein (CRP) levels (between 3 and 10 mg/L) for atherosclerotic events have generated considerable interest, as well as a degree of controversy and confusion. CRP concentrations in this range are found in about one third of the American population. To better understand the mechanisms underlying minor elevation of CRP, we have surveyed its reported associations with a variety of states and conditions. It has become clear that even minimal environmental irritants and inflammatory stimuli elicit a minor CRP response. Minor CRP elevation has been found associated with a number of genetic polymorphisms, with membership in different demographic and socioeconomic groups, with a variety of dietary patterns and with many medical conditions that are not apparently inflammatory. Finally, minor CRP elevation bears negative prognostic implications for many conditions, particularly age-related diseases, and predicts mortality in both diseased and apparently healthy individuals. In sum, minor CRP elevation is associated with a great many diverse conditions, some of which are, or may prove to be, causal. Many of these reported associations imply a mild degree of tissue stress or injury, suggesting the hypothesis that the presence of distressed cells, rather than a resulting inflammatory response, is commonly the stimulus for CRP production.

Effect of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on high-sensitivity C-reactive protein levels

Cardiovascular disease is the leading cause of death among adults in the United States, in Europe, and in much of Asia. Despite advances in primary prevention of coronary artery disease, including early detection and treatment of dyslipidemia, one half of all myocardial infarctions and strokes occur in patients with normal serum cholesterol levels. Observations like this prompt the search for new risk factors and improved identification of individuals at high risk. One proposed risk factor is an elevated level of C-reactive protein (CRP), a marker of inflammation independent of other risk factors. The CRP assay is desirable in terms of standardization and cost. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are indicated for the treatment of dyslipidemias, but data support their protective role against cardiovascular disease beyond their effects on lipids. Statins directly affect inflammatory markers, and nearly 2 dozen randomized studies have demonstrated statins' effects on CRP. Because information regarding the role of CRP in cardiovascular disease is compelling but sometimes contradictory and because the need to reduce CRP levels is unclear, the American Heart Association and the Centers for Disease Control and Prevention presented a panel statement on the topic. Ongoing trials will assist in determining the need to reduce CRP levels to lower cardiovascular risk. An understanding of these issues is important for improving the prediction of cardiovascular risk and for intervening to reduce this risk.

FcγRIIB Mediates C-Reactive Protein Inhibition of Endothelial NO Synthase

C-reactive protein (CRP) is an acute-phase reactant that is positively correlated with cardiovascular disease risk and endothelial dysfunction. Whether CRP has direct actions on endothelium and the mechanisms underlying such actions are unknown. Here we show in cultured endothelium that CRP prevents endothelial NO synthase (eNOS) activation by diverse agonists, resulting in the promotion of monocyte adhesion. CRP antagonism of eNOS occurs nongenomically and is attributable to blunted eNOS phosphorylation at Ser1179. Okadaic acid or knockdown of PP2A by short-interference RNA reverses CRP antagonism of eNOS, indicating a key role for the phosphatase. Aggregated IgG, the known ligand for Fcγ receptors, causes parallel okadaic acid–sensitive loss of eNOS function, FcγRIIB expression is demonstrable in endothelium, and heterologous expression studies reveal that CRP antagonism of eNOS requires FcγRIIB. In FcγRIIB +/+ mice, CRP blunts acetylcholine-induced increases in carotid artery vascular conductance; in contrast, CRP enhances acetylcholine responses in FcγRIIB −/− mice. Thus FcγRIIB mediates CRP inhibition of eNOS via PP2A, providing a mechanistic link between CRP and endothelial dysfunction.

Early prognostic usefulness of C-reactive protein added to the Thrombolysis In Myocardial Infarction risk score in acute coronary syndromes

The aim of the present study was to evaluate whether an elevated plasma C-reactive protein (CRP) level provides any additional prognostic information to the validated Thrombolysis In Myocardial Infarction (TIMI) risk score in patients with acute coronary syndromes. For this purpose, 1,846 consecutive patients with either acute ST-segment elevation myocardial infarction (STEMI; 861 patients) or non-ST-segment elevation acute coronary syndrome (NSTEACS; 985 patients) were included. The incidence of 30-day death and 14-day composite of death, myocardial infarction (or repeat myocardial infarction) and recurrent ischemia was the prespecified primary end point in the STEMI and NSTEACS cohorts, respectively. The incidence of the primary end point was 9.8% and 23.6% in the STEMI and NSTEACS cohorts, respectively. A significantly increased risk of the primary end point was present with an increase in the STEMI and NSTEACS TIMI risk score (p(trend) < 0.001 for the 2 groups). A plasma CRP value of > or = 5 and > or = 3 mg/L (defined by receiver-operating characteristic analysis) was associated with a significantly increased risk of the primary end point in the STEMI and NSTEACS cohorts, respectively (p < 0.001 for the 2 cohorts), and it was true throughout the subgroups of STEMI and NSTEACS TIMI risk scores. In conclusion, an elevated plasma CRP level appears to be a marker that adds prognostic information to the validated STEMI and NSTEACS TIMI risk score. The plasma CRP and TIMI risk score may be used together for enhanced risk stratification in the setting of acute coronary syndromes.

C-reactive protein in patients with acute coronary syndrome: correlation with diagnosis, myocardial damage, ejection fraction and angiographic findings

BACKGROUND

C-reactive protein (CRP) plasmatic levels increase in patients with acute coronary syndromes (ACS). Correlations between CRP levels, myocardial functional damage and cardiomyocyte lysis remain to be defined.

METHODS

192 consecutive patients with acute coronary syndromes (64.97 +/- 11.08 mean age, 71.35% male gender) were included in the study; 138 patients (71.87%) were discharged with an acute myocardial infarction (AMI) diagnosis (28 with non Q-wave AMI) and 54 with an unstable angina (UA) diagnosis (28.13%). In all patients CRP, CK, LDH, CK-MB and troponin I plasmatic concentrations were evaluated every 6 h for 48 h and every 24 h for the following 2 days from the onset of symptoms. Ejection fraction was estimated by bidimensional echocardiography and extension of myocardial lysis by cardiac enzymes plasmatic release. 92 patients (67 with AMI, 25 with UA) underwent coronary-angiography. Incidence of adverse cardiac events was recorded in a 6 months follow up.

RESULTS

Mean CRP levels in Q-wave MI showed a statistically significant increase in the different blood samples with baseline. Mean CRP levels of the three groups were not statistically different at baseline and after 6, 12, and 18 h. Q-wave AMI CRP levels showed a statistically significant difference as against non Q-wave AMI at 36 (p < 0.05), 48 (p < 0.05) and 72 h (p < 0.05) and UA at 24 (p < 0.01), 30 (p < 0.01), 48 (p < 0.0001), 72 (p = 0.0001) and 96 h (p = 0.0003); non Q-wave AMI CPR levels showed a statistically significant difference as against UA at 48 h (p < 0.01). CRP peak mean levels were significantly different when comparing Q-wave AMI patients with UA patients (8.21 +/- 7.85 vs. 2.75 +/- 3.33 mg/dl, p < 0.001). In patients with Q-wave AMI there was a correlation between CRP peak concentrations and CK (r = 0.264, p = 0.008) and LDH (r = 0.32, p = 0.001), while correlation with CK-MB peak concentrations was not statistically significant (r = 0.196, p = 0.051). In the same patient group, there was also a correlation between CRP plasmatic concentrations and troponin I plasmatic concentrations from the 30th to 96th h after the onset of symptoms (r = 0.38-0.53, p < 0.05). No correlation was found between CRP levels and ejection fraction and angio-coronarography findings (number of stenotic vessels, culprit lesions, ruptured plaques). Peak CRP levels were associated in a 6 months follow up with an increased incidence of major adverse cardiac events (MACEs) in patients with Q-wave AMI (HR 1.1649, 95% C.I. 1.0197-1.3307, p < 0.05).

CONCLUSIONS

CRP plasmatic concentrations showed a different release curve in patients with Q-wave AMI in comparison with patients with non Q-wave AMI and with patients with UA. CRP peak concentrations did not correlate with ejection fraction and angiographic findings, but correlate with incidence of MACE. The increase in CRP levels during Q-wave MI seems to be linked to the extension of myocardial damage rather than pre-existing inflammation.

Acute myocardial infarction in young patients: nutritional status and biochemical factors

PURPOSE

The aim of this study was to establish whether nutritional status and biochemical factors, C-reactive protein (CRP), serum amyloid A (SAA) protein, serum iron (Fe) and fibrinogen at admission were different in patients with acute myocardial infarction (AMI) at a young age (<40 years) vs. those with AMI at an older age (>60 years). We also investigated whether during the stay in the hospital, the increase in acute-phase reactants was different in young vs. older subjects, and if dyslipidemic aspects were different between the two groups.

METHODS

The study population consisted of 40 patients, all males with a mean age of 36.7+/-1.16 years, admitted to our facility with AMI. The control group included 40 patients, all males, mean age of 66.3+/-4.24 years, with AMI. CRP, SAA, Fe and fibrinogen were determined at admission to the hospital and daily for 7 days in the two groups of patients.

RESULTS

In young patients the median value of the highest levels were 6.2 mg/l (range 0.7-27.30) for CRP, 13.22 mg/l (range 0.7-130) for SAA, 420 mg/dl (range 76-840) for fibrinogen and 49.1 gamma/ml (range 14-102) for Fe levels. In the older patients, the median value of the highest levels were 5.9 mg/l (range 0.6-28.30) for CRP, 12.12 mg/l (range 0.9-280) for SAA, 480 mg/dl (range 60-780) for fibrinogen and 47.1 gamma/ml (range 12-94) for Fe levels.

CONCLUSIONS

In the present study, acute-phase reactants were quantitatively similar in young and old patients. On the contrary, nutritional status, homocysteine, LDL and triglycerides are significantly higher in young patients than in old patients.

High-sensitivity serum C-reactive protein levels in subjects with or without myocardial infarction or periodontitis

BACKGROUND

Serum high-sensitivity C-reactive protein (hsC-rp) is a non-specific marker of inflammation. Elevated hsC-rp levels are found in subjects with cardiovascular diseases (CVDs). Periodontitis may influence hsC-rp levels.

OBJECTIVES

To assess periodontal status and hsC-rp serum levels in consecutive subjects hospitalized and diagnosed with acute myocardial infarction (AMI) (n=85) and in a group of carefully matched subjects (gender, age social, ethnic, and smoking habits) without clinical evidence of CVD (n=63).

METHODS

hsC-rp levels, other routine serum values, and clinical periodontal conditions were studied.

RESULTS

Subjects with AMI had higher hsC-rp levels than control subjects (p<0.001, Mann-Whitney U-test). The odds that subjects in the control group with periodontitis (30% or more sites with>4.0 mm loss of alveolar bone) had serum hsC-rp>1.8 mg/l was 1.5 (95% CI: 1.1-7.3, p<0.05). Stepwise linear regression analysis failed to include periodontal parameters in an explanatory model to hsC-rp values. Only the serum leucocyte (white blood cell (WBC)) counts were explanatory to hsC-rp values (beta standard coefficient=0.45, t=3.2, p<0.001). Serum WBC counts were significantly higher in control subjects with periodontitis (p<0.03) but not in subjects in the AMI group (p<0.57).

CONCLUSIONS

(1) As expected, elevated serum hsC-rp concentration and serum WBC counts are associated with acute coronary heart disease. (2) Elevated serum hsC-rp values are associated with radiographically defined periodontitis in subjects with no evidence of CVD. (3) Periodontal parameters are not explanatory to elevated serum hsC-rp values if serum WBC and low-density lipoprotein counts are included in the regression model.

Inflammation, insulin resistance, and glucose intolerance in acute myocardial infarction patients without a previous diagnosis of diabetes mellitus

We examined the prevalence of impaired glucose metabolism and its association with inflammation and insulin resistance (IR) in acute myocardial infarction (AMI) patients without a previous diagnosis of diabetes. This prospective study enrolled 52 AMI patients, and 75-g oral glucose tolerance testing was performed on 30 patients at discharge and again 3 months later. We also measured serum adiponectin, high sensitive C-reactive protein, and IL-6 on both occasions. Data were compared with those of 30 type 2 diabetic patients without a history of AMI. Forty percent and 36.7% of AMI patients had impaired glucose tolerance (IGT) at discharge and at 3 months, respectively. The corresponding proportions for newly diagnosed diabetes are 33.0% and 30.0%. At discharge, AMI patients with IGT or diabetes showed higher high sensitive C-reactive protein and IL-6 levels compared with AMI patients with normal glucose tolerance or control type 2 diabetic patients. Furthermore, AMI patients with IGT or diabetes exhibited higher IR and lower serum adiponectin levels than AMI patients with normal glucose tolerance at 3 months after discharge. Previously undiagnosed diabetes and IGT are common in Korean patients with AMI. These glycometabolic abnormalities are associated with inflammation, IR, and serum adiponectin levels.

CDC/AHA Workshop on Markers of Inflammation and Cardiovascular Disease

Inflammation is a recognized key component of acute coronary syndromes. Such pathogenetic achievement has led to the use of inflammatory cells and proteins as prognostic markers in these syndromes. A number of markers have been proposed, including proinflammatory cytokines such as interleukin-6, interleukin-1RA, and tumor necrosis factor-α, adhesion molecules such as intracellular adhesion molecule-1 and vascular adhesion molecule-1 and markers of cell activation. Although all are of scientific interest, the clinical use of these markers is limited by their high cost, low availability, and unfavorable biological profile. Conversely, common markers of inflammation such as C-reactive protein (CRP), the prototypic acute phase protein, and to a lesser extent fibrinogen, have been proven to be reliable and important markers of risk in ischemic heart disease. CRP, in particular, has been found to be associated with short- and long-term prognosis in acute coronary syndromes, including ST-elevation myocardial infarction, and in stable angina, and to predict the risk of restenosis and major events, including death, after revascularization procedures. CRP has been consistently found to be independent from other risk factors and to have an incremental value beyond the common risk factors and biochemical markers of risk, including troponin. Whether CRP also should be used as a guide to therapy is still a matter of discussion that deserves further, properly designed studies.

Should C-reactive protein be added to metabolic syndrome and to assessment of global cardiovascular risk?

Of novel risk factors for cardiovascular disease currently under investigation, high-sensitivity C-reactive protein (hsCRP) is the most promising. To date, more than 20 prospective epidemiologic studies have demonstrated that hsCRP independently predicts vascular risk, 6 cohort studies have confirmed that hsCRP evaluation adds prognostic information beyond that available from the Framingham Risk Score, and 8 cohort studies have demonstrated additive prognostic value at all levels of metabolic syndrome or in the prediction of type 2 diabetes. In contrast to several other biomarkers that also reflect biological aspects of inflammation, hypofibrinolysis, and insulin resistance, hsCRP measurement is inexpensive, standardized, widely available, and has a decade-to-decade variation similar to that of cholesterol. Given the consistency of prognostic data for hsCRP and the practicality of its use in outpatient clinical settings, we believe the time has come for a careful consideration of adding hsCRP as a clinical criterion for metabolic syndrome and for the creation of an hsCRP-modified coronary risk score useful for global risk prediction in both men and women. Toward this end, we believe experts in the fields of epidemiology, prevention, vascular biology, and clinical cardiology should be convened to begin discussing the merits of this proposal.

White Blood Cell Count and C-reactive Protein Predict Short-term Prognosis in Acute Myocardial Infarction

An elevated white blood cell (WBC) count and C-reactive protein (CRP) concentration are associated with acute myocardial infarction (AMI) and long-term mortality in patients with coronary artery disease. Their relationship with short-term prognosis following AMI is less clear, however. We investigated the relationship between WBC count and CRP concentration, obtained at the time of admission, and the development of subsequent ischaemic coronary events (SICE) within 30 days of AMI in 177 patients. After adjustment for confounding factors, CRP concentration was found to be a strong independent predictor for SICE within 30 days in patients with AMI. WBC count was not found to be an independent predictor, but there was a strong correlation between high WBC counts and the onset of SICE within 30 days in patients with AMI. We conclude that CRP concentration and WBC count could be used to predict the short-term prognosis of patients with AMI.