Cardiovascular risk prediction by N-terminal pro brain natriuretic peptide and high sensitivity C-reactive protein is affected by age and sex

Triglyceride-glucose index improves risk prediction beyond traditional risk factors and hypertension mediated organ damage in healthy adults

BACKGROUND AND AIMS

Triglyceride-glucose (TyG) index, a surrogate measure of insulin resistance, is associated with hypertension mediated organ damage (HMOD) and cardiovascular disease. This study investigated the association between TyG index and major adverse cardiovascular events (MACE) and its interaction with traditional risk factors and HMOD.

METHODS AND RESULTS

Healthy subjects recruited from the general population were thoroughly examined and followed for MACE using nation-wide registries. Cox proportional hazard models were used to calculate the association between TyG index and MACE occurrence. Models were adjusted for Systematic Coronary Risk Evaluation (SCORE) risk factors, pulse wave velocity, left ventricular mass index, carotid atherosclerotic plaque status, and microalbuminuria. Continuous net reclassification and Harrell's Concordance index (C-index) were used to assess the added prognostic value of TyG index. During a follow-up period of mean 15.4 ± 4.7 years, MACE were observed in 332 (17%) of 1970 included participants. TyG index was associated with MACE; HR = 1.44 [95%CI:1.30-1.59] per standard deviation. After adjustment for traditional cardiovascular (CV) risk factors, HR was 1.16 [95%CI:1.03-1.31]. The association between TyG index and MACE remained significant after further adjustment for each HMOD component. However, this finding was evident only in subjects aged 41 or 51 years (HR = 1.39; 95%CI:1.15-1.69). Including TyG index in a risk model based on traditional CV risk factors improved C-index with 0.005 (P = 0.042).

CONCLUSION

In this population-based study of healthy middle-aged subjects, TyG index was associated with MACE independently of traditional CV risk factors and HMOD. TyG index may have a potential role in future risk prediction systems.

Association between antecedent blood pressure, hypertension-mediated organ damage and cardiovascular outcome

Purpose: The objective of this study was to test if combining antecedent systolic blood pressure (SBP) with traditional risk factors and hypertension-mediated organ damage (HMOD) improves risk stratification for subsequent cardiovascular disease.Materials and methods: 1910 subjects participated in this study. Antecedent SBP was defined as the average of measurements obtained in 1982 and in 1987. Current SBP was obtained in 1993. HMOD were examined in 1993. HMOD was defined as either atherosclerotic plaque(s), increased pulse wave velocity, increased urine albumin creatinine ratio (above the 90th percentile) or left ventricular hypertrophy. Major adverse cardiovascular events (MACE) including myocardial infarction, cerebrovascular disease, heart failure and arrhythmia were obtained from national registries.Results: Subjects were divided into two age categories: a middle-aged group (aged 41 or 51) and an older group (aged 61 or 71). From 1993 to 2010, 425 events were observed. In multivariable analysis with both current and antecedent SBP adjusted for traditional risk factors, current SBP was associated with each measure of HMOD whilst antecedent SBP was not significantly associated with urine albumin creatinine ratio in the older group, LVMI in the middle-aged group, or the presence of plaque in any of the age groups (all p > 0.15). When current and antecedent SBP were evaluated together, current SBP was not associated with MACE in the middle-aged subgroup [HR = 1.09 (0.96-1.22), p = 0.18] but remained associated with MACE in the older subgroup [HR = 1.21 (1.10-1.34), p < 0.01]. Contrariwise, antecedent SBP was only associated with MACE in the middle-aged subgroup [HR = 1.24 (1.04-1.48), p = 0.02]. Adding antecedent SBP to traditional risk factors did not improve the predictive accuracy of the survival model.Conclusion: In healthy non-medicated middle-aged subjects, antecedent SBP is associated with cardiovascular outcome independently of current BP, traditional risk factors and HMOD. However, improvement in risk stratification seems to be limited.

Impact of Age and Target-Organ Damage on Prognostic Value of 24-Hour Ambulatory Blood Pressure

Markers of target-organ damage and 24-hour ambulatory blood pressure (BP) measurement improve cardiovascular risk stratification. The prevalence of target-organ damage and raised BP increases with aging. The study aim was to evaluate the impact of age and target-organ damage on the prognostic value of ambulatory BP. Markers of target-organ damage and ambulatory BP were measured in 1408 healthy people aged 41 or 51 (middle-aged group), and 61 or 71 (older group) years. The primary outcome was cardiovascular events after 16 years of follow-up, with data obtained from national registries. The prognostic value of BP was evaluated with Cox regression models, adjusted for traditional risk factors and target-organ damage, including left ventricular mass, pulse wave velocity, carotid plaques, and urine albumin/creatinine ratio. A total of 323 events were observed. In comparison with traditional risk factors, adding systolic BP and presence of target-organ damage improved risk stratification by increasing concordance index from 0.711 to 0.728 ( P =0.01). In middle-aged subjects with target-organ damage, increment in pulse pressure (hazard ratio, 1.70; 95% confidence interval, 1.31–2.21; P <0.01) and increment in average real variability (hazard ratio, 1.29; 95% confidence interval, 1.05–1.59; P =0.02) were associated with a greater risk of cardiovascular disease compared with subjects without target-organ damage: hazard ratio, 1.04 (95% confidence interval, 0.74–1.46; P =0.81); P for interaction, 0.02; and hazard ratio, 0.89 (95% confidence interval, 0.69–1.14; P =0.36); P for interaction, 0.01. Target-organ damage may be a marker of individual susceptibility to the harmful effects of pulse pressure and BP variability on the cardiovascular system in middle-aged individuals.

Risk stratification and treatment effect of statins in secondary cardiovascular prevention in old age: Additive value of N-terminal pro-B-type natriuretic peptide

BACKGROUND

To date, no validated risk scores exist for prediction of recurrence risk or potential treatment effect for older people with a history of a cardiovascular event. Therefore, we assessed predictive values for recurrent cardiovascular disease of models with age and sex, traditional cardiovascular risk markers, and 'SMART risk score', all with and without addition of N-terminal pro-B-type natriuretic peptide (NT-proBNP). Treatment effect of pravastatin was assessed across low and high risk groups identified by the best performing models.

DESIGN AND METHODS

Post-hoc analysis in 2348 participants (age 70-82 years) with a history of cardiovascular disease within the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) study. Composite endpoint was a recurrent cardiovascular event/cardiovascular mortality.

RESULTS

The models with age and sex, traditional risk markers and SMART risk score had comparable predictive values (area under the curve (AUC) 0.58, 0.61 and 0.59, respectively). Addition of NT-proBNP to these models improved AUCs with 0.07 (p for difference ((pdiff)) = 0.003), 0.05 (pdiff = 0.009) and 0.06 (pdiff < 0.001), respectively. For the model with age, sex and NT-proBNP, the hazard ratio for the composite endpoint in pravastatin users compared with placebo was 0.67 (95% confidence interval 0.49-0.90) for those in the highest third of predicted risk and 0.91 (0.57-1.46) in the lowest third, number needed to treat 12 and 115 (pdiff = 0.038) respectively.

CONCLUSION

In secondary cardiovascular prevention in old age addition of NT-proBNP improves prediction of recurrent cardiovascular disease, cardiovascular mortality and treatment effect of pravastatin. A minimal model including age, sex and NT-proBNP predicts as accurately as complex risk models including NT-proBNP.

High-sensitivity C-reactive protein predicts adverse cardiovascular events in patients with Takayasu arteritis with coronary artery involvement

The study aimed to assess the association of high-sensitivity C-reactive protein (hsCRP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) to major adverse cardiovascular events (MACE) in Takayasu arteritis (TA) patients with coronary artery disease (CAD). Data on 60 TA patients with CAD and 60 age- and severity-matched patients with CAD hospitalized in Fuwai Hospital from 2005 to August 2014 were assessed. The clinical features, laboratory data, coronary angiographic findings, treatment, and follow-up outcomes were summarized retrospectively. MACE were defined as death from cardiac causes, myocardial infarction, nonfatal target vessel revascularization, or rehospitalization due to unstable or progressive angina. CAD patients had more atherogenic lipid and lipoprotein profiles such as lower levels of high-density lipoprotein cholesterol (HDL-C) (1.0 ± 0.2 vs. 1.3 ± 0.3 mmol/L, p = 0.01) and higher levels of low-density lipoprotein cholesterol (LDL-C) (2.5 ± 0.9 vs. 2.2 ± 1.1 mmol/L, p = 0.04) in contrast with TA-CAD patients. During a mean follow-up period of 3.2 years, 31 patients with Takayasu coronary arteritis reached the endpoint. Multivariate Cox proportional hazards model demonstrated that log(hsCRP) (HR = 5.3, 95 % CI = 1.1-27.8, p = 0.04) was a significant and independent predictor of MACE in patients with Takayasu coronary arteritis. Elevated baseline levels of hsCRP predict cardiovascular events, independent of other prognostic markers in TA-related CAD patients.

Association between albuminuria, atherosclerotic plaques, elevated pulse wave velocity, age, risk category and prognosis in apparently healthy individuals

METHOD

Two thousand and fifty-nine healthy individuals aged 41, 51, 61 and 71 years examined in 1993, were divided in age, SCORE and Framingham risk score (FRS) groups. Subclinical vascular damage (SVD) was defined as carotid-femoral pulse wave velocity (cfPWV) at least 12 m/s, carotid atherosclerotic plaques or albuminuria defined as urine albumin/creatinine ratio at least 90th percentile of 0.73/1.06 mg/mmol men/women. In 2006, the composite endpoint (CEP) of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke and hospitalization for ischemic heart disease was recorded (n = 229).

RESULTS

With increasing age, SCORE or FRS risk group, prevalence of cfPWV at least 12 m/s (5.2, 14.5, 35.3, 53.5% or 4.4, 15.6, 50.9, 66.1% or 4.0, 9.5, 32.1, 56.1%), atherosclerotic plaque (4.0, 19.0, 35.3, 53.5% or 3.5, 16.8, 43.7, 55.9%, or 6.6, 7.6, 9.8, 20.0%) and albuminuria (7.9, 8.7, 11.4, 20.6% or 7.9, 8.2, 16.6, 19.5% or 6.6, 7.6, 9.8, 20.0%) increased, all P < 0.001.CEP was associated with albuminuria in individuals aged 61 or 71 years, with moderate or very high SCORE or intermediate or high FRS (all P < 0.05), with atherosclerotic plaques in individuals aged 41, 51 or 61 years, with moderate SCORE or with high-intermediate or high FRS (all P < 0.01), and with cfPWV at least 12 m/s in individuals aged 51 years (P < 0.001) or high FRS (P < 0.05). Presence of at least one SVD was significantly associated with an increased risk in individuals aged 51 [hazard ratio 2.7 (1.6-4.8)] and 61 years [hazard ratio 2.7 (1.5-4.7)], moderate [hazard ratio 2.4 (1.6-3.7)] or high SCORE risk group [hazard ratio 2.3 (1.2-4.7)] and low-intermediate [hazard ratio 3.3 (1.5-7.0)], high-intermediate [hazard ratio 2.3 (1.5-3.5)] and high FRS risk group [hazard ratio 2.0 (1.4-3.0)].

CONCLUSION

SVD and especially atherosclerotic plaques or urine albumin/creatinine ratio (UACR) at least 0.73/1.06 mg/mmol (men/women) added prognostic information in individuals aged 51 or 61 years or with moderate or intermediate risk.

Prediction of clinical outcomes using B-type natriuretic peptides in the general population: a systematic review

The use of B-type natriuretic peptides to predict outcomes in general populations has been investigated in a number of primary studies. A previous systematic review considering natriuretic peptides in cardiovascular disease included a subgroup of general population studies, which suggested an association with a number of clinical outcomes. We electronically searched Medline, Embase, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL for English-language articles published between 1989 and mid-2012. We utilized trained reviewers and standardized forms to screen articles for inclusion and extract data from included articles. All included studies (n = 7) were summarized in narrative and tabular form. A general population was defined as one that was randomly selected from a community setting where no specific inclusion or exclusion criteria were specified. The seven included studies all used FDA approved assays for NT-proBNP. The range of clinical outcomes and heterogeneity did not allow for meta-analysis. The hazard ratios for predicting outcomes in the included studies ranged from 1.0 to 4.1 (all p values <0.05). The discrimination statistics reported in four studies all demonstrated statistically significant improvements in predicting outcomes. NT-proBNP is associated with heart failure, all-cause and cardiovascular mortality, and other combined cardiovascular events in a general unselected population. The discrimination statistics suggest modest improvements in risk stratification. No prospective studies exist to demonstrate the clinical utility of using B-type natriuretic peptides to predict clinical outcomes in a general population.

N-terminal pro-B-type natriuretic peptide and stroke risk: the reasons for geographic and racial differences in stroke cohort

BACKGROUND AND PURPOSE

Improved identification of those at risk of stroke might improve prevention. We evaluated the association of the cardiac function biomarker N-terminal pro-B-type natriuretic peptide (NT-proBNP) with stroke risk in the 30 239 black and white participants of the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort.

METHODS

During 5.4 years of follow-up after enrollment in 2003 to 2007, NT-proBNP was measured in baseline blood samples of 546 subjects with incident ischemic stroke and 956 without stroke.

RESULTS

NT-proBNP was higher with older age and in those with heart disease, kidney disease, atrial fibrillation, and lower low-density lipoprotein-cholesterol. Adjusting for age, race, sex, income, education, and traditional stroke risk factors, there was an increased risk of stroke across quartiles of NT-proBNP; participants with NT-proBNP in the top versus the bottom quartile had a hazard ratio of 2.9 (95% confidence interval, 1.9-4.5). There was no impact of added adjustment for kidney function and heart failure. Among pathogenetic stroke subtypes, the association was largest for cardioembolic stroke, with a hazard ratio of 9.1 (95% confidence interval, 2.9-29.2). Associations did not differ by age, sex, or race, or after excluding those with baseline heart failure or atrial fibrillation. Predicted stroke risk was more accurate in 27% of participants if NT-proBNP was considered after traditional stroke risk factors (P<0.001).

CONCLUSIONS

NT-proBNP was a major independent risk marker for stroke. Considering this and other data for stroke, coronary disease, and atrial fibrillation, the clinical use of NT-proBNP measurement in primary prevention settings should be considered.

Amino-terminal pro-B-type natriuretic peptide and high-sensitivity C-reactive protein but not cystatin C predict cardiovascular events in male patients with peripheral artery disease independently of ambulatory pulse pressure

BACKGROUND

Patients with peripheral arterial disease (PAD) are at high risk for cardiovascular (CV) events. We have previously shown that ambulatory pulse pressure (APP) predicts CV events in PAD patients. The biomarkers amino-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitivity C-reactive protein (hs-CRP), and cystatin C are related to a worse outcome in patients with CV disease, but their predictive values have not been studied in relation to APP.

METHODS

Blood samples and 24-hour measurements of ambulatory blood pressure were examined in 98 men referred for PAD evaluation during 1998-2001. Patients were followed for a median of 71 months. The outcome variable was CV events defined as either CV mortality or any hospitalization for myocardial infarction, stroke, or coronary revascularization. The predictive values of log(NT-proBNP), log(hs-CRP), and log(cystatin C) alone and together with APP were assessed by multivariable Cox regression. Area under the curve (AUC) and net reclassification improvement (NRI) were calculated compared with a model containing other significant risk factors.

RESULTS

During follow-up, 36 patients had at least 1 CV event. APP, log(NT-proBNP), and log(hs-CRP) all predicted CV events in univariable analysis, whereas log(cystatin C) did not. In multivariable analysis log(NT-proBNP) (hazard ratio (HR) = 1.62; 95% confidence interval (CI) = 1.05-2.51) and log(hs-CRP) (HR = 1.63; 95% CI = 1.19-2.24) predicted events independently of 24-hour PP. The combination of log(NT-proBNP), log(hs-CRP), and average day PP improved risk discrimination (AUC = 0.833 vs. 0.736; P < 0.05) and NRI (37%; P < 0.01) when added to other significant risk factors.

CONCLUSIONS

NT-proBNP and hs-CRP predict CV events independently of APP and the combination of hs-CRP, NT-proBNP, and day PP improves risk discrimination in PAD patients.

Plasma B-type natriuretic peptide in predicting outcomes of elective coronary artery bypass surgery

The risks of surgery and its clinical outcome are of great importance for both patients and physicians when choosing coronary artery bypass (CABG) surgery for coronary artery disease. The purpose of the current study was to clarify the relationship between serum B-type natriuretic peptide (BNP) and patient clinical outcome. Seventy-six eligible patients who underwent CABG were enrolled into the prospective study. Venous blood samples were drawn for serum BNP and N-terminal (NT)-proBNP levels measurement on preoperative Day 1, postoperative Day 1, and postoperative Day 7. Clinical end points were: (1) intensive care unit (ICU) stay longer than 4 days postoperatively and/or hospital stay longer than 13 days postoperatively; (2) major complications and poor outcomes. Patients who had prolonged ICU stay and hospitalization had significantly higher postoperative Day 1 BNP and postoperative Day 1 NT-proBNP level (p = 0.02 and 0.005, respectively). Age was significantly older in patients with prolonged ICU stay and hospitalization than those without prolonged ICU stay and hospitalization (p = 0.03). Serum creatinine level was also significantly increased in patients with prolonged ICU stay and hospitalization (p = 0.009). However, age was the only remaining factor that correlated with prolonged ICU stay and hospitalization in the multivariate logistic regression model. These results suggest that research using BNP and NT-proBNP for predicting ICU stay and hospitalization in patients who have undergone CABG must adjust risk factors to present a more appropriate estimation of its clinical outcome.

Can ambulatory blood pressure measurements substitute assessment of subclinical cardiovascular damage?

OBJECTIVE

We have previously demonstrated that markers of subclinical organ damage (SOD) improve cardiovascular risk prediction in healthy individuals. We wanted to investigate whether this additive effect of SOD was due to inaccurate blood pressure (BP) measurement or whether ambulatory BP (AMBP) added further to risk prediction.

METHODS

In a population cohort of 1385 Danish individuals free of cardiovascular disease and diabetes, we recorded traditional risk factors, AMBP and pulse wave velocity (PWV), urine albumin/creatinine ratio (UACR), left ventricular mass index (LVMI) and carotid atherosclerotic plaques at baseline. A composite cardiovascular endpoint (CEP) consisting of cardiovascular death and nonfatal myocardial infarction and stroke was recorded in national registries.

RESULTS

During a median follow-up of 12.8 years, a total of 119 CEPs occurred. In categorical analysis, presence of SOD as well as masked hypertension increased sensitivity of Systemic Coronary Risk Estimation from 73.9 to 89.1% (P < 0.001) and reduced specificity from 60.1 to 41.8% (P < 0.001). In continuous analysis, logUACR [hazard ratio = 1.20 (95% confidence interval [CI] 1.05-1.38), P = 0.009], atherosclerotic plaques [hazard ratio = 1.82 (95% CI 1.21-2.74), P = 0.004] and 24-h SBP [hazard ratio = 1.34 (95% CI 1.12-1.60), P = 0.002] but not logPWV or LVMI predicted CEP in a model with adjustments for age, sex, conventional BP, total cholesterol and smoking. Compared with a risk model using only traditional risk factors, adding PWV, UACR, plaques, LVMI and 24-h SBP increased C-index significantly from 0.76 to 0.79% and produced a net reclassification improvement of 23.3% (P = 0.001).

CONCLUSION

UACR and plaques predicted cardiovascular events independently of AMBP and improved risk prediction.

Developing and assessing cardiovascular biomarkers

Atherosclerosis is a slow process that over time can lead to fatal events. Early identification and prediction of future risk can allow for preventive strategies to be instituted. There is an increasing interest in utilizing novel biomarkers in cardiovascular disease screening and management. These novel biomarkers may help in cardiovascular disease risk assessment and treatment monitoring, and some may be treatment targets. To be useful for risk prediction, novel biomarkers need to show a significant association with cardiovascular disease events and bring additional value in risk stratification when added to known risk prediction models. Biomarkers used for treatment monitoring need to show that they can serve as good surrogates of cardiovascular disease status. In this article, we present 3 biomarkers that are currently approved by the U.S. Food and Drug Administration for use in cardiovascular disease management and risk assessment: C-reactive protein, lipoprotein-associated phospholipase A2, and myeloperoxidase. Other new biomarkers have also been shown recently to help in cardiovascular disease risk prediction and management. In this article, we will review 2 of these new biomarkers: cardiac troponin T measured by a highly sensitive assay and brain natriuretic peptide.

Association between arterial stiffness and pulmonary function in hypertensive patients

Arterial stiffness, assessed by cardio-ankle vascular index (CAVI), is clinically used to assess arteriosclerosis. Recently, pulmonary age, as determined by pulmonary function test, has been proposed by the Japanese Respiratory Society as a diagnostic measure for chronic obstructive pulmonary disease (COPD). This study aims to examine the association between CAVI and pulmonary function and to elucidate the correlation between vascular stiffness and pulmonary age in hypertensive patients. We enrolled a total of 45 hypertensive patients (70±9 years) who had been taking antihypertensive medications for at least 1 year. Pulmonary function was measured by the percentage of predicted forced vital capacity (FVC) and the ratio of forced expiratory volume in 1 s (FEV(1)) to FVC (FEV(1)/FVC ratio). Pulmonary age was determined by the equation proposed by the Japanese Respiratory Society. CAVI was measured at the same clinic visit. In the simple correlation analysis CAVI correlated with the FEV(1)/FVC ratio (r=-0.399, P=0.007) and pulmonary age (r=0.559, P<0.001). Multiple linear regression analysis revealed that CAVI was independently associated with FEV(1)/FVC ratio (β=-0.418, P=0.014) and pulmonary age (β=0.514, P=0.002). In addition, CAVI was significantly higher in patients with increased pulmonary age (9.4±1.4) than in those with normal pulmonary age (8.4±0.9) (P=0.011). The present study indicates that an increased CAVI is independently associated with reduced pulmonary function and increased pulmonary age. Hypertensive patients with high CAVI may need to be monitored for the progression of COPD.

Association between high-sensitivity C-reactive protein and left ventricular diastolic function assessed by echocardiography in patients with cardiovascular risk factors

High-sensitivity C-reactive protein (hsCRP) has been demonstrated to play a causal role in atherosclerosis and to predict cardiovascular events in the general population. On the other hand, left ventricular (LV) hypertrophy and diastolic dysfunction assessed by echocardiography can also predict cardiovascular events in patients with cardiovascular risk factors. However, there are few data regarding the relationships among hsCRP, LV hypertrophy, and diastolic function. We examined the relationships among hsCRP, LV hypertrophy, and diastolic function in 185 patients (65±11 years), who had no overt heart disease, but had cardiovascular risk factors, including hypertension, diabetes, and dyslipidemia. Echocardiography was performed to measure the left ventricular mass index (LVMI) as a parameter of LV hypertrophy. LV diastolic function was assessed by the ratio (E/A) of early (E) and late (A) diastolic transmitral flows, early diastolic mitral annular velocity (E'), and the ratio (E/E') of E to E' using Doppler echocardiography. The hsCRP was correlated with LVMI (r=0.228, p=0.002), E' (r=-0.276, p<0.001), and E/E' (r=0.419, p<0.001). The E/E' as a parameter of LV diastolic function showed the closest correlation to hsCRP. These results indicate that elevated hsCRP reflects LV diastolic dysfunction rather than LV hypertrophy. We therefore suggest that hsCRP may be a marker of subclinical LV diastolic dysfunction in patients with cardiovascular risk factors.

N-terminal pro B-type natriuretic peptide (NT pro-BNP) is a predictor of long-term survival in male patients of 75 years and older with high-grade asymptomatic internal carotid artery stenosis

BACKGROUND

Carotid endarterectomy (CEA) is commonly performed for asymptomatic high-grade internal carotid artery (ICA) stenosis to prevent stroke. However, despite advancing age of the society, for patients older than 75 years, there is no recommendation by the European guidelines for CEA, as this age group might not benefit from this intervention due to a limited life expectancy.

OBJECTIVE

We assessed N-terminal pro B-type natriuretic peptide (NT pro-BNP) as a predictive marker for long-term survival in this particular patient population in order to stratify patients for an improved surgical outcome.

METHODS

In a nonrandomized single-center clinical trial, we prospectively studied mortality rates of 205 consecutive patients (80 women, 125 men; mean age, 75 ± 10 years) with asymptomatic high-grade ICA stenosis in relation to preoperative plasma NT pro-BNP levels. We estimated cumulative survival over 5 years by Kaplan-Meier curves and established a proportional hazard-model by Cox regression.

RESULTS

In male patients, higher levels of preoperative NT pro-BNP levels were associated with a significantly increased long-term mortality. Those 75 years or older had the same survival rate as younger patients, if NT pro-BNP levels were low, making them thus eligible for CEA.

CONCLUSIONS

The results of our study suggest that preoperative plasma levels of NT pro-BNP are a valuable tool for the stratification of male patients. Male patients older than 75 years with low levels of NT pro-BNP should be referred for carotid revascularization, as they will most likely enjoy the benefit of surgery.

Interactions among gender, age, hypertension and C-reactive protein in coronary vasospasm

BACKGROUND

Coronary vasospasm (CVsp) has been reported to be an inflammatory disease, reflected by elevated high-sensitivity C-reactive protein (hs-CRP). We investigated the interactions among gender, age, hypertension and hs-CRP in patients with CVsp.

MATERIALS AND METHODS

We retrospectively examined 722 Taiwanese patients with or without CVsp during an 8-year period. None of the patients had obstructive coronary artery disease. Serum hs-CRP levels were examined in a subset of 375 patients to evaluate the interactions of hs-CRP with gender, age, smoking and hypertension in the development of CVsp.

RESULTS

In women, only the highest hs-CRP tertile (> 3 mg L⁻¹) was independently associated with CVsp. In men, age > 58 years and the highest hs-CRP tertile were independently associated with CVsp. In women, elevated risk was only demonstrated in patients ≤ 58 years of age with hs-CRP levels in the highest tertile. In men, a positively monotonic trend was demonstrated between hs-CRP levels and CVsp in those > 58 years of age. The odds ratios of CVsp in both women and men with hs-CRP in the highest tertile reduced from 6·01 to 1·48 and 6·35-2·69 respectively, if they had hypertension.

CONCLUSION

The relationship between hs-CRP and CVsp differed between men and women. Our findings that there is a non-threshold model in men and a threshold model in women provide evidence that more smokers in men (life-style) and age (induction time) contribute to the natural history of CVsp development. The negative effect of hypertension on CVsp suggests that the pathogenesis of CVsp differs from that of coronary atherosclerosis.

Risk prediction is improved by adding markers of subclinical organ damage to SCORE

AIMS

It is unclear whether subclinical vascular damage adds significantly to Systemic Coronary Risk Evaluation (SCORE) risk stratification in healthy subjects.

METHODS AND RESULTS

In a population-based sample of 1968 subjects without cardiovascular disease or diabetes not receiving any cardiovascular, anti-diabetic, or lipid-lowering treatment, aged 41, 51, 61, or 71 years, we measured traditional cardiovascular risk factors, left ventricular (LV) mass index, atherosclerotic plaques in the carotid arteries, carotid/femoral pulse wave velocity (PWV), and urine albumin/creatinine ratio (UACR) and followed them for a median of 12.8 years. Eighty-one subjects died because of cardiovascular causes. Risk of cardiovascular death was independently of SCORE associated with LV hypertrophy [hazard ratio (HR) 2.2 (95% CI 1.2-4.0)], plaques [HR 2.5 (1.6-4.0)], UACR > or = 90th percentile [HR 3.3 (1.8-5.9)], PWV > 12 m/s [HR 1.9 (1.1-3.3) for SCORE > or = 5% and 7.3 (3.2-16.1) for SCORE < 5%]. Restricting primary prevention to subjects with SCORE > or = 5% as well as subclinical organ damage, increased specificity of risk prediction from 75 to 81% (P < 0.002), but reduced sensitivity from 72 to 65% (P = 0.4). Broaden primary prevention from subjects with SCORE > or = 5% to include subjects with 1% < or = SCORE < 5% together with subclinical organ damage increased sensitivity from 72 to 89% (P = 0.006), but reduced specificity from 75 to 57% (P < 0.002) and positive predictive value from 11 to 8% (P = 0.07).

CONCLUSION

Subclinical organ damage predicted cardiovascular death independently of SCORE and the combination may improve risk prediction.

Utility of C-reactive protein for cardiovascular risk stratification across three age groups in subjects without existing cardiovascular diseases

The relative utility of conventional and novel risk factors in predicting cardiovascular disease (CVD) in relation to age remains unclear. We examined the discriminative ability of C-reactive protein (CRP) and Framingham risk score across young (35 to 50 years), middle (51 to 65 years), and older (> or =65 years) aged participants from the Scottish Health Surveys (n = 5,944, 44.5% men). CRP data and conventional risk factors were collected at baseline. During an average follow-up of 7.1 years, 308 CVD events (a composite of fatal and nonfatal events incorporating acute myocardial infarction, coronary artery bypass surgery, percutaneous coronary angioplasty, stroke, and heart failure) occurred. The log CRP/SD predicted the risk of CVD events in middle-age (hazard ratio 2.20, 95% confidence interval 1.34 to 3.61) and older (hazard ratio 1.85, 95% confidence interval 1.23 to 2.78) participants, after adjustment for the Framingham risk score. Using receiver operating characteristic (ROC) curves, the area under the curve for the Framingham risk factor model for predicting CVD events was greater in the younger (ROC 0.78) and middle-age (ROC 0.72) participants than in the older participants (ROC 0.59), although the discriminative ability was not substantially improved by adding the CRP data. In conclusion, our results have demonstrated the steadily decreasing predictive value of conventional risk factors with advancing age, although CRP has limited additive value for CVD risk stratification. Our results provide validation of the recently devised Framingham risk factor algorithm for use in primary care in participants <65 years old.

Is it time to change the definition of normal urinary albumin excretion?

This Practice Point commentary discusses a recent study by Forman et al. that examined the association between baseline urinary albumin:creatinine ratio and the risk of developing hypertension among 2,179 women in the first and second Nurses' Health Studies who did not have hypertension or diabetes at baseline and had normoalbuminuria by conventional definitions. The study showed that quartiles of albuminuria beyond the lowest quartile were increasingly predictive of subsequent hypertensive disease, even at levels well below what is conventionally considered to be the normal range. This commentary highlights the importance of evaluating albuminuria as an indicator of target organ damage and a risk factor for cardiovascular disease. Patients without hypertension, diabetes or other cardiovascular diseases who have albuminuria should be considered at risk of cardiovascular disease and should undergo intensive follow-up. In addition, although previous studies have indicated that cardiovascular risk increases exponentially with increasing levels of albuminuria, the definition of the threshold for albuminuria should be dependent on concomitant cardiovascular disease (i.e. lower levels of albuminuria should be considered pathologic if concomitant cardiovascular disease is not present).

Impact of the metabolic syndrome on the predictive values of new risk markers in the general population

Although the metabolic syndrome (MetS) is positively associated with high-sensitivity C-reactive protein (hsCRP), negatively associated with N-terminal pro-brain natriuretic peptide (Nt-proBNP) and inconsequently related to urine albumin/creatinine ratio (UACR) they are all associated with cardiovascular events. Therefore, we wanted to determine the influence of MetS on the predictive values of UACR, hsCRP and Nt-proBNP. On the basis of the definition of MetS by the International Diabetes Federation, a Danish population sample of 1983 apparently healthy subjects was divided into three groups: 530 subjects without any elements of MetS, 1093 subjects with some elements of MetS and 360 subjects with MetS. During the following 9.5 years the composite end point of cardiovascular death, non-fatal myocardial infarction or stroke (composite cardiovascular end point, CEP) occurred in 204 subjects. In Cox-regression analyses adjusting for age, gender and smoking, all three cardiovascular risk markers predicted CEP independently of MetS. Despite no significant interaction with MetS, high log(hsCRP) was associated with CEP primarily in subjects without any elements of MetS (hazard ratio (HR)=4.5 (1.5-14.0), P<0.01), log(Nt-proBNP) primarily in subjects with some elements of MetS (HR=3.0 (1.6-5.6), P<0.01), and logUACR independently of elements of MetS. Pre-specified gender-adjusted (men/women) cutoff values of hsCRP > or = 6.0/7.3 mg l(-1) predicted CEP in subjects without elements of MetS with positive and predictive values of 11.5 and 98%, respectively. UACR > or = 0.73/1.06 mg mmol(-1) predicted CEP in subjects with MetS with positive and predictive values of 23.5 and 93%, respectively. In apparently healthy subjects, high hsCRP was associated with CEP primarily in subjects without MetS, high Nt-proBNP in subjects with elements of MetS and UACR independently of MetS.