Midregional Proadrenomedullin for Prediction of Cardiovascular Events in Coronary Artery Disease: Results from the AtheroGene Study

Mid-Regional Proadrenomedullin Levels in Primary Immunodeficiencies Complicated with Pulmonary Manifestations

The development of lower respiratory complications in children with primary immunodeficiencies characterized by recurrent infections significantly contributes to morbidity and mortality. This is clinically more important and specific in the evaluation of prognosis. The inflammatory response that develops throughout the clinical process can cause the release of several biomarkers. This study aimed to evaluate the inflammatory biomarker "mid-regional pro-adrenomedullin (MR-proADM)" levels by distribution of lower respiratory tract complications. Plasma MR-proADM levels were measured in children with (n = 52) and without (n = 103) lower respiratory tract complications. The complicated group was also evaluated as "infective and non-infective" groups. The median MR-proADM levels were higher in the complicated cases (p = 0.175). It was 205.5 (73.4- 562.6) ng/L in the infective group while it was 96.1 (26.1-43.3) ng/L in the non-infective group and the difference between the two groups was statistically significant (p = 0.003). The predictive value of MR-proADM (AUC = 0.749, p = 0.003) was statistically significant compared to CRP (AUC = 0.330, p = 0.040) and SAA (AUC = 0.261, p = 0.004) in the infective group. This study evidences that the MR-proADM levels are higher in PID cases with infective pulmonary complications. Among other markers, MR-proADM appears to be a particularly good predictive inflammation marker for these children.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12291-022-01061-9.

Emerging biomarkers for the detection of cardiovascular diseases

Background

The prevalence of cardiovascular disease (CVD) has been continuously increasing, and this trend is projected to continue. CVD is rapidly becoming a significant public health issue. Every year there is a spike in hospital cases of CVD, a critical health concern in lower- and middle-income countries. Based on identification of novel biomarkers, it would be necessary to study and evaluate the diagnostic requirements or CVD to expedite early detection.

Main body

The literature review was written using a wide range of sources, such as well-known medical journals, electronic databases, manuscripts, texts, and other writings from the university library. After that, we analysed the specific markers of CVD and compiled a systematic review. A growing body of clinical research aims to identify people who are at risk for cardiovascular disease by looking for biomolecules. A small number of biomarkers have been shown to be useful and reliable in medicine. Biomarkers can be used for a variety of clinical applications, such as predicting heart disease risk, diagnosing disease, or predicting outcomes. As a result of the ability for a single molecule to act as a biomarker, its usefulness in medicine is expected to increase significantly.

Conclusions

Based on assessing the current trends in the application of CVD markers, we discussed and described the requirements for the application of CVD biomarkers in coronary heart disease, cerebrovascular disease, rheumatic heart disease, and other cardiovascular illnesses. Furthermore, the current review focuses on biomarkers for CVD and the procedures that should be considered to establish the comprehensive nature of the expression of biomarkers for cardiovascular illness.

Plasma Adrenomedullin, Allelic Variations in the ADM Gene, and Risk for Lower-Limb Amputation in People With Type 2 Diabetes

OBJECTIVE

Patients with diabetes have an increased risk for lower-limb amputation (LLA), but biomarkers to assess risk of LLA are lacking. Adrenomedullin (ADM) is a vasodilator peptide that also plays a role in fluid and electrolyte homeostasis in the kidney, increasing natriuresis and diuresis. ADM was shown to be associated with cardiovascular and renal events in diabetes, but it was not investigated in terms of LLA risk. We investigated the hypothesis that ADM is associated with LLA in people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We studied 4,375 participants in the DIABHYCAR and SURDIAGENE cohorts (men, 68%; mean 66 years of age; mean duration of diabetes 12 years; and median follow-up 5.3 years). Plasma midregional proadrenomedullin (MR-proADM; a surrogate for ADM) was measured by immunofluorescence. Five single nucleotide polymorphisms (SNPs) in the ADM gene region were genotyped.

RESULTS

LLA requirement during follow-up by increasing tertiles of plasma MR-proADM distribution was 1.0% (tertile 1 [T1]), 2.3% (T2), and 4.4% (T3) (P < 0.0001). In Cox multivariate analysis, the adjusted hazard ratio (95% CI) for LLA was 4.40 (2.30-8.88) (P < 0.0001) for T3 versus T1. Moreover, MR-proADM significantly improved indices for risk stratification of LLA. Four SNPs were associated with plasma MR-proADM concentration at baseline and with LLA during follow-up. Alleles associated with higher MR-proADM were associated with increased LLA risk.

CONCLUSIONS

We observed associations of plasma MR-proADM with LLA and of ADM SNPs with plasma MR-proADM and with LLA in people with type 2 diabetes. This pattern of Mendelian randomization supports the causality of the association of ADM with LLA.

Association between MR-proADM concentration and treatment intensity of antihypertensive agents in chronic kidney disease patients with insufficient blood pressure control

Response to antihypertensive drugs in patients with chronic kidney disease (CKD) has great interindividual variability. Adrenomedullin (ADM) is produced abundantly in hypertension, but clearance is very rapid. Mid-regional proADM (MR-proADM) produced from an ADM precursor is considered a surrogate biomarker for quantification of ADM. We investigated the association of MR-proADM with antihypertensive resistance in CKD patients with poor blood pressure (BP) control. This cross-sectional study analyzed 33 CKD patients with poor BP control defined as failure to achieve target BP despite at least two classes of antihypertensive drugs. Treatment intensity score was calculated to facilitate comparability of antihypertensive regimens across subjects taking different drugs. Plasma MR-proADM concentration was measured using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Plasma MR-proADM concentration correlated with estimated glomerular filtration rate (eGFR) (r =  - 0.777, p < 0.001). Treatment intensity score correlated positively with plasma MR-proADM concentration (r = 0.355, p = 0.043), and the correlation was further enhanced after correction by weight (r = 0.538, p = 0.001). Single and multiple regression analysis identified MR-proADM concentration (p = 0.005) as independently associated with weight-corrected treatment intensity score. MR-proADM may be useful as a biomarker to determine the therapeutic intensity of antihypertensive drugs in CKD patients with poor BP control.

Mid-regional pro-adrenomedullin is a novel biomarker for arterial stiffness as the criterion for vascular failure in a cross-sectional study

We investigated the potential of mid-regional pro-adrenomedullin (MR-proADM) for use as a novel biomarker for arterial stiffness as the criterion for vascular failure and cardiometabolic disease (obesity, hypertension, dyslipidemia, diabetes, and metabolic syndrome) compared with high-sensitivity C-reactive protein (hsCRP). Overall, 2169 individuals (702 men and 1467 women) were enrolled. Multiple regression analysis was performed to assess the association of MR-proADM and hsCRP with brachial-ankle pulse wave velocity (baPWV), adjusting for other variables. The diagnostic performance (accuracy) of MR-proADM with regard to the index of vascular failure was tested with the help of receiver operating characteristic curve analysis in the models. MR-proADM was significantly higher in participants with vascular failure, as defined by baPWV and/or its risk factors (obesity, hypertension, dyslipidemia, diabetes, and metabolic syndrome), than in control groups. Independent of cardiovascular risk factors (age, drinking, smoking, body mass index, systolic blood pressure, lipid and glycol metabolism), MR-proADM was significantly associated with baPWV, and MR-proADM showed higher areas under the curve of baPWV than hsCRP showed. MR-proADM is more suitable for the diagnosis of higher arterial stiffness as the criterion for vascular failure than hsCRP. Because vascular assessment is important to mitigate the most significant modifiable cardiovascular risk factors, MR-proADM may be useful as a novel biomarker on routine blood examination.

Mortality in cardiogenic shock is stronger associated to clinical factors than contemporary biomarkers reflecting neurohormonal stress and inflammatory activation

PURPOSE

To validate the IABP-SHOCK II risk score in a Danish cohort and assess the association between the IABP-SHOCK II risk score and admission concentration of biomarkers reflecting neurohormonal - (Copeptin, Pro-atrial natriuretic peptide (proANP), Mid-regional pro-adrenomedullin (MRproADM)) and inflammatory (ST2) activation in patients with CS complicating ST segment elevation myocardial infarction (STEMI).

METHODS

A total of 137 consecutive patients admitted with STEMI and CS at two tertiary heart centres were stratified according to the IABP-SHOCK II risk score (0-2; 3/4; 5-9), and had blood sampled upon admission.

RESULTS

Plasma concentrations of Copeptin (median (pmol/L) score 0-2: 313; score 3/4: 682; score 5-9: 632 p < 0.0001), proANP (pmol/L) (1459; 2225; 2876 p = 0.0009) and MRproADM (nmol/L) (0.86; 1.2; 1.4 p = 0.04) were significantly associated with the risk score, whereas ST2 (ng/mL) was not (44; 60; 45 p = 0.23). The IABP-SHOCK II risk score predicted 30-day mortality (score 0-2: 22%; score 4/3: 51%; score 5-9: 72%, area under the curve (AUC): 0.73, plogrank < 0.0001), while the tested biomarkers did not (AUC: 0.51<plogrank < 0.57).

CONCLUSION

Plasma concentrations of Copeptin, MRproADM and proANP were associated with the IABP-SHOCK II risk score in STEMI patients admitted with CS. The risk score predicted 30-day mortality, with no improvement in prediction when concentrations of the assessed biomarkers were added.

Multimarker Approach to Identify Patients with Coronary Artery Disease at High Risk for Subsequent Cardiac Adverse Events: The Multi-Biomarker Study

In our prospective non-randomized, single-center cohort study (n = 161), we have evaluated a multimarker approach including S100 calcium binding protein A12 (S100A1), interleukin 1 like-receptor-4 (IL1R4), adrenomedullin, copeptin, neutrophil gelatinase-associated lipocalin (NGAL), soluble urokinase plasminogen activator receptor (suPAR), and ischemia modified albumin (IMA) in prediction of subsequent cardiac adverse events (AE) during 1-year follow-up in patients with coronary artery disease. The primary endpoint was to assess the combined discriminatory predictive value of the selected 7 biomarkers in prediction of AE (myocardial infarction, coronary revascularization, death, stroke, and hospitalization) by canonical discriminant function analysis. The main secondary endpoints were the levels of the 7 biomarkers in the groups with/without AE; comparison of the calculated discriminant score of the biomarkers with traditional logistic regression and C-statistics. The canonical correlation coefficient was 0.642, with a Wilk’s lambda value of 0.78 and p < 0.001. By using the calculated discriminant equation with the weighted mean discriminant score (centroid), the sensitivity and specificity of our model were 79.4% and 74.3% in prediction of AE. These values were higher than that of the calculated C-statistics if traditional risk factors with/without biomarkers were used for AE prediction. In conclusion, canonical discriminant analysis of the multimarker approach is able to define the risk threshold at the individual patient level for personalized medicine.

Copeptin, myeloperoxidase and pro-adrenomedullin for acute coronary syndrome in patients with chronic kidney disease

Objectives:

Copeptin, myeloperoxidase and pro-adrenomedullin have emerged as potential biomarkers for diagnosis and prognosis of acute coronary syndrome (ACS). However, their applicability in patients with chronic kidney disease (CKD) remains unknown as these patients were excluded from previous studies. Our objective was to determine the superior novel cardiac marker to predict 30-day and six-month adverse cardiac events (ACEs) defined as cardiac-related death, myocardial infarction and ventricular fibrillation.

Methods:

A prospective observational study was carried out. Patients were included if they presented to the emergency department with symptoms suggestive of ACS and had CKD as defined as a serum creatinine of more than 130 µmol/l. Copeptin, myeloperoxidase and pro-adrenomedulin assays were performed. Occurrence of ACE was traced from review of the patients’ case records and the registry of deaths.

Results:

A total of 724 patients were recruited: 60.6% were male and 68.6% were Chinese. The median age was 67 years. Among those recruited, 88.3% had CKD stages 4 and 5, with 33.5% on dialysis. The rates of ACE at 30 days and six months were 15.1% and 21.7%, respectively. All readings of the three biomarkers were not significantly different in patients with ACE compared with those without both at 30 days and six months. The areas under the curve for copeptin, myeloperoxidase and pro-adrenomedullin were 0.53, 0.50 and 0.45, respectively ( p > 0.05).

Conclusions:

The poor performance of the biomarkers may be attributable to lack of specificity for ACS, as elevated levels could be from other causes in CKD patients. Routine testing cannot be recommended.

Plasma midregional proadrenomedullin (MR-proADM) concentrations and their biological determinants in a reference population

BACKGROUND

Midregional proadrenomedullin (MR-proADM) is emerging as a prognostic biomarker for detecting the failure of multiple organs. Establishment of scientifically robust reference intervals facilitates interpretation of laboratory test results. The objectives of this study were (i) to establish reliable reference intervals for plasma MR-proADM using a commercially available automated fluoroimmunoassay in apparently healthy individuals, and (ii) to identify biological determinants of MR-proADM concentrations.

METHODS

A total of 506 questionnaire-identified apparently healthy adults were enrolled in a single-center, cross-sectional study. A final reference group (n=172) was selected after exclusion of obese individuals, those with increased values of laboratory biomarkers indicating asymptomatic myocardial injury or dysfunction, ongoing inflammation, diabetes, dyslipidemia and renal dysfunction and outliers.

RESULTS

The 2.5th and 97.5th percentile intervals for MR-proADM values in the reference group (90% confidence interval) were 0.21 (0.19-0.23) and 0.57 (0.55-0.59) nmol/L, respectively. Although older age, higher values of HbA1c, C-reactive protein, B-type natriuretic peptide and body mass index, together with a history of smoking and a decreased estimated glomerular filtration rate were significantly associated with increasing concentrations of MR-proADM in both univariate and multivariate analyses, magnitudes of these relationships were modest and did not substantially influence MR-proADM reference intervals. Sex-dependent difference in MR-proADM reference intervals was not detected [0.19 (0.16-0.22)-0.56 (0.54-0.60) nmol/L in females vs. 0.22 (0.20-0.25)-0.58 (0.57-0.63) nmol/L in males].

CONCLUSIONS

Our study successfully established robust reference intervals for MR-proADM concentrations in plasma. Considering the negligible influence of potential biological determinants on plasma MR-proADM, we recommend the adoption of single reference intervals for adult population as a whole.

Prognostic value of plasma MR-proADM vs NT-proBNP for heart failure in people with type 2 diabetes: the SURDIAGENE prospective study

AIMS/HYPOTHESIS

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is the gold standard prognostic biomarker for diagnosis and occurrence of heart failure. Here, we compared its prognostic value for the occurrence of congestive heart failure with that of plasma mid-region pro-adrenomedullin (MR-proADM), a surrogate for adrenomedullin, a vasoactive peptide with vasodilator and natriuretic properties, in people with type 2 diabetes.

METHODS

Plasma MR-proADM concentration was measured in baseline samples of a hospital-based cohort of consecutively recruited participants with type 2 diabetes. Our primary endpoint was heart failure requiring hospitalisation.

RESULTS

We included 1438 participants (age 65 ± 11 years; 604 women and 834 men). Hospitalisation for heart failure occurred during follow-up (median 64 months) in 206 participants; the incidence rate of heart failure was 2.5 (95% CI 2.2, 2.9) per 100 person-years. Plasma concentrations of MR-proADM and NT-proBNP were significantly associated with heart failure in a Cox multivariable analysis model when adjusted for age, diabetes duration, history of coronary heart disease, proteinuria and baseline eGFR (_adjHR [95%CI] 1.83 [1.51, 2.21] and 2.20 [1.86, 2.61], respectively, per 1 SD log₁₀ increment, both p < 0.001). MR-proADM contributed significant supplementary information to the prognosis of heart failure when we considered the clinical risk factors (integrated discrimination improvement [IDI, mean ± SEM] 0.021 ± 0.007, p = 0.001) (Table 3). Inclusion of NT-proBNP in the multivariable model including MR-proADM contributed significant complementary information on prediction of heart failure (IDI [mean ± SEM] 0.028 ± 0.008, p < 0.001). By contrast, MR-proADM did not contribute supplementary information on prediction of heart failure in a model including NT-proBNP (IDI [mean ± SEM] 0.003 ± 0.003, p = 0.27), with similar results for heart failure with reduced ejection fraction and preserved ejection fraction.

CONCLUSIONS/INTERPRETATION

MR-proADM is a prognostic biomarker for heart failure in people with type 2 diabetes but gives no significant complementary information on prediction of heart failure compared with NT-proBNP.

Midregional pro-atrial natriuretic peptide is a superior biomarker to N-terminal pro-B-type natriuretic peptide in the diagnosis of heart failure patients with preserved ejection fraction

OBJECTIVES

To explore that if mid-regional sequence of pro-A-type natriuretic peptide (MR-proANP) may have a good value of diagnosis in heart failure with preserved ejection fraction (HFpEF) compared with N-terminal pro-B-type natriuretic peptide (NT-proBNP).

METHODS

Participants with cardiovascular disease who were enrolled in this study were divided into the nonheart failure (non-HF) group (n = 75), HFpEF group (n = 65), and HF with reduced ejection fraction (HFrEF) group (n = 50). The MR-proANP and NT-proBNP levels in plasma from all patients were measured by enzyme-linked immunosorbent assay.

RESULTS

The plasma levels of MR-proANP and NT-proBNP in HFpEF and HFrEF groups were higher than those in non-HF group (P < .05). MR-proANP levels were significantly different (P < .05) in different New York Heart Association class patients with HFpEF. In the diagnostic analysis area under the curve of MR-proANP (0.844) was higher than that of NT-proBNP (0.518, P < .001). The left atrial volume index in the HFrEF group was higher than HFpEF group (P < .05); however, both of these groups had a higher index than non-HF group (P < .05).

CONCLUSION

Results indicated that MR-proANP may be more sensitive and specific than NT-proBNP in diagnosing HFpEF. It may be used as a potential diagnostic biomarker in patients with HFpEF.

MR-proADM as a Prognostic Marker in Patients With ST-Segment-Elevation Myocardial Infarction-DANAMI-3 (a Danish Study of Optimal Acute Treatment of Patients With STEMI) Substudy

Background

Midregional proadrenomedullin (MR‐proADM) has demonstrated prognostic potential after myocardial infarction (MI). Yet, the prognostic value of MR‐proADM at admission has not been examined in patients with ST‐segment–elevation MI (STEMI).

Methods and Results

The aim of this substudy, DANAMI‐3 (The Danish Study of Optimal Acute Treatment of Patients with ST‐segment–elevation myocardial infarction), was to examine the associations of admission concentrations of MR‐proADM with short‐ and long‐term mortality and hospital admission for heart failure in patients with ST‐segment–elevation myocardial infarction. Outcomes were assessed using Cox proportional hazard models and area under the curve using receiver operating characteristics. In total, 1122 patients were included. The median concentration of MR‐proADM was 0.64 nmol/L (25th–75th percentiles, 0.53–0.79). Within 30 days 23 patients (2.0%) died and during a 3‐year follow‐up 80 (7.1%) died and 38 (3.4%) were admitted for heart failure. A doubling of MR‐proADM was, in adjusted models, associated with an increased risk of 30‐day mortality (hazard ratio, 2.67; 95% confidence interval, 1.01–7.11; P=0.049), long‐term mortality (hazard ratio, 3.23; 95% confidence interval, 1.97–5.29; P<0.0001), and heart failure (hazard ratio, 2.71; 95% confidence interval, 1.32–5.58; P=0.007). For 30‐day and 3‐year mortality, the area under the curve for MR‐proADM was 0.77 and 0.78, respectively. For 3‐year mortality, area under the curve (0.84) of the adjusted model marginally changed (0.85; P=0.02) after addition of MR‐proADM.

Conclusions

Elevation of admission MR‐proADM was associated with long‐term mortality and heart failure, whereas the association with short‐term mortality was borderline significant. MR‐proADM may be a marker of prognosis after ST‐segment–elevation myocardial infarction but does not seem to add substantial prognostic information to established clinical models.

Clinical Trial Registration

URL: http://www.ClinicalTrials.gov/. Unique identifiers: NCT01435408 and NCT01960933.

Preoperative Midregional Pro-Adrenomedullin and High-Sensitivity Troponin T Predict Perioperative Cardiovascular Events in Noncardiac Surgery

OBJECTIVE

We evaluated the utility of preoperative midregional (MR) pro-adrenomedullin (proADM) and cardiac troponin T (TnT) for improved detection of patients at high risk for perioperative cardiac events and mortality after major noncardiac surgery.

SUBJECTS AND METHODS

This prospective, single-center, observational study enrolled 79 patients undergoing major noncardiac surgery. After initial clinical assessment (clinical history, physical examination, echocardiogram, blood tests, and chest X-ray), MR-proADM and high-sensitivity TnT (hsTnT) were measured within 48 h prior to surgery by immunoluminometric and electrochemiluminescence immunoassay. Patients were followed by the consulting physician until discharge or up to 14 days in the hospital after surgery. Perioperative cardiac events included myocardial infarction and development or aggravation of congestive heart failure. Data were compared between patients who developed target events and event-free patients.

RESULTS

Within 14 days of monitoring, 14 patients (17.72%) developed target events: 9 (11.39%) died and 5 (6.33%) developed cardiovascular events. The average age of the patients was 71.29 ± 6.62 years (range: 55-87). Sex, age, and hsTnT did not significantly differ between groups. MR- proADM concentration was higher in deceased patients (p = 0.01). The upper quartile of MR-proADM was associated with a fatal outcome (66.7 vs. 20.0%, p < 0.01) and with cardiovascular events (64.3 vs. 16.9%, p < 0.01). MR-proADM above the cutoff value (≥0.85) was associated with a fatal outcome (88.9 vs. 20.0%, p < 0.01) and cardiovascular events (71.4 vs. 28.6%, p < 0.01); this association was not observed for hsTnT.

CONCLUSION

Preoperative measurement of MR-proADM provides useful information for perioperative cardiac events in high-risk patients scheduled for noncardiac surgery.

Pro-Adrenomedullin predicts 10-year all-cause mortality in community-dwelling patients: a prospective cohort study

Background

Several studies found mid-regional pro-adrenomedullin (ProADM), the prohormone of the cardiovascular protein adrenomedullin, to be strongly associated with short-term mortality, mostly in the inpatient setting. We evaluated associations of ProADM levels with 10-year mortality in community-dwelling primary care patients with respiratory tract infections.

Methods

This is a post-hoc analysis using clinical and biomarker data of 134 primary care patients with respiratory tract infections. ProADM was measured on admission and after 7 days in batch-analysis. 10-year follow-up data was collected by GP, patient and relative tracing through phone interviews. We calculated Cox regression models and area under the receiver operating characteristics curves to assess associations of ProADM with 10-year all-cause mortality.

Results

During the 10-year follow-up 6% of included patients died. Median baseline ProADM blood levels (nmol/l) were significantly higher in non-survivors compared to survivors (0.5, IQR 0.4–1.3; vs. 0.2, IQR 0.1–0.5; p = 0.02) and showed a significant association with 10-year all-cause mortality in an age-adjusted cox regression model (HR: 2.5, 95%-CI: 1.0–6.1, p = 0.04). ProADM levels on day 7 showed similar results.

Conclusions

This posthoc analysis found an association of elevated ProADM blood levels and 10-year all-cause mortality in a primary care cohort with respiratory tract infections. Due to the methodological limitations including incomplete data regarding follow-up information and biomarker measurement, this study warrants validation in future larger studies.

Trial registration

Current Controlled Trials, SRCTN73182671

Prognostic value of human mature adrenomedullin in patients with acute myocardial infarction

Adrenomedullin (ADM) correlates with adverse cardiovascular outcomes in patients with acute myocardial infarction (AMI) and in patients with heart failure. Measurement of human mature ADM (mADM) has been difficult, and recent studies have used its surrogate - the mid-regional pro-ADM (MRproADM). Our objective was to determine whether mADM measured by a novel sandwich immunoassay, using the anti-C-terminal and an anti-mid-regional monoclonal antibody, was prognostic of 30-day, 90-day, 1-year, and 2-year major adverse cardiovascular events (MACEs) in 1111 consecutive patients who have suffered an AMI. We also compared it with the effect of MRproADM in the same patient population. A total of 311 (27.0%) patients experienced the primary endpoint at 2 years follow-up. The median (inter-quartile range) of mADM was significantly higher in patients who experienced a 2-year MACE [60.90 (44.00-86.97)] pg/ml, compared to event-free survivors [49.59 (36.20-68.15)] pg/ml (P < 0.001). mADM, taken as 1 SD of the continuous variable, was predictive of MACEs in multivariate analysis, with hazard ratios [95% confidence intervals (CIs)] at 90 days [1.28 (1.01-1.62)], 1 year [1.31 (1.08-1.59)], and 2 years [1.42 (1.07-1.64)]. It was also independently predictive of death at 1-year [1.52 (1.12-2.05)] and 2-year [1.42 (1.07-1.89)] follow-up. mADM was a better predictor of these outcomes than MRproADM, apart from death at 90 days, and combined death and heart failure hospitalization at 1 and 2 years, respectively. Human mADM can be reliably measured and predicts MACE events at medium-term follow-up, and confirms the paradigm of risk stratification using MRproADM - a surrogate for the active hormone. The relationship between mADM and MACE appears to be a continuum.

Candidate biomarkers in heart failure with reduced and preserved ejection fraction

CONTEXT

Patients presenting with heart failure symptoms are categorized into heart failure (HF) with reduced and preserved ejection fraction.

OBJECTIVE

Aim is to investigate the additional use of candidate biomarkers to characterize patients with either sub-type of HF.

METHODS

Literature search was conducted in the electronic databases MEDLINE and Cochrane Central Register of Controlled Trials from inception through November 2014.

RESULTS

The results of 47 diseased and general population cohorts were included.

CONCLUSION

Current studies could outline the additional use of candidate biomarkers especially GDF-15, MR-proADM and high-sensitive determined troponin, although major outcome studies are still missing.

Inflammation biomarkers and mortality prediction in patients with type 2 diabetes (ZODIAC-27)

BACKGROUND

C-reactive protein (CRP), procalcitonin (PCT) and pro-adrenomedullin (MR-proADM) are inflammation markers associated with long-term mortality risk. We compared the associations and predictive capacities of CRP, PCT and MR-proADM with cardiovascular and all-cause mortality in patients with type 2 diabetes.

METHODS

This study included primary care treated patients with type 2 diabetes participating in the ZODIAC cohort study. A total of 1005 out of 1688 patients (60%) had complete baseline variables. Baseline CRP, PCT and MR-proADM were assessed in relation to cardiovascular and all-cause mortality with Cox proportional hazard analyses. Hazard Ratios (HR) were adjusted for age, gender, BMI, smoking, systolic blood pressure, cholesterol-HDL ratio, duration of diabetes, HbA1c, history of cardiovascular diseases, albumin-creatinine ratio and creatinine. Risk prediction capabilities were assessed with Harrell's C statistics and proportion of explained variance (R(2)).

RESULTS

After a median follow-up of 11 years, 472 (47%) of 1005 patients had died. The likelihood ratio test showed that CRP and MR-proADM significantly improved prediction in cardiovascular mortality [HRs 1.20 (95%CI 1.09-1.33) and 1.56 (95%CI 1.06-2.30)] and in all-cause mortality [HRs 1.10 (95%CI: 1.03-1.18) and 1.31 (95%CI 1.02-1.69)]. Harrell's C values and R(2) measures showed slightly improved discrimination for cardiovascular mortality in patients without macrovascular disease (C: 0.80 to 0.81; R(2): 0.50 to 0.52) and MR-proADM (C: 0.80 to 0.82; R(2): 0.50 to 0.52).

CONCLUSIONS

CRP and MR-proADM, but not PCT, were independently associated with cardiovascular and all-cause mortality. In patients without macrovascular diseases, CRP and MR-proADM slightly improved discrimination, in absolute sense, of patients at risk for cardiovascular mortality.

Association of metabolic complications with plasma mid-regional pro-adrenomedullin level in stable kidney transplant recipients

BACKGROUND

Recently, increased plasma mid-regional pro-adrenomedullin (MR-proADM) concentrations have been demonstrated in patients with chronic renal failure. In this study, we attempted to identify significant clinical factors associated with MR-proADM concentration in stable kidney transplant recipients.

METHODS

Forty-seven Japanese kidney transplant recipients who underwent transplantation >180days prior to the study were analyzed. To facilitate comparability of anti-hypertensive regimens across recipients taking different drugs, we calculated the treatment intensity score of anti-hypertensive drugs in each recipient. Morning blood samples were collected and plasma MR-proADM concentrations were measured using an enzyme immunoassay.

RESULTS

Multiple regression analysis identified treatment intensity score for anti-hypertensive drugs, serum albumin, creatinine clearance and use of lipid-lowering agents as significant independent factors associated with plasma MR-proADM concentration. Adjusted coefficient of determination for this model was 0.46.

CONCLUSION

Apart from indicating lowered renal function, plasma MR-proADM concentration may be a useful biomarker for metabolic disorders, especially hypertension and hyperlipidemia, in stable kidney transplant patients.

The prognostic blood biomarker proadrenomedullin for outcome prediction in patients with chronic obstructive pulmonary disease (COPD): a qualitative clinical review

Plasma proadrenomedullin (ProADM) is a blood biomarker that may aid in multidimensional risk assessment of patients with chronic obstructive pulmonary disease (COPD). Co-secreted 1:1 with adrenomedullin (ADM), ProADM is a less biologically active, more chemically stable surrogate for this pluripotent regulatory peptide, which due to biological and ex vivo physical characteristics is difficult to reliably directly quantify. Upregulated by hypoxia, inflammatory cytokines, bacterial products, and shear stress and expressed widely in pulmonary cells and ubiquitously throughout the body, ADM exerts or mediates vasodilatory, natriuretic, diuretic, antioxidative, anti-inflammatory, antimicrobial, and metabolic effects. Observational data from four separate studies totaling 1366 patients suggest that as a single factor, ProADM is a significant independent, and accurate, long-term all-cause mortality predictor in COPD. This body of work also suggests that combined with different groups of demographic/clinical variables, ProADM provides significant incremental long-term mortality prediction power relative to the groups of variables alone. Additionally, the literature contains indications that ProADM may be a global cardiopulmonary stress marker, potentially supplying prognostic information when cardiopulmonary exercise testing results such as 6-min walk distance are unavailable due to time or other resource constraints or to a patient's advanced disease. Prospective, randomized, controlled interventional studies are needed to demonstrate whether ProADM use in risk-based guidance of site-of-care, monitoring, and treatment decisions improves clinical, quality-of-life, or pharmacoeconomic outcomes in patients with COPD.

Plasma Adrenomedullin and Allelic Variation in the ADM Gene and Kidney Disease in People With Type 2 Diabetes

Production of adrenomedullin (ADM), a vasodilator peptide, increases in response to ischemia and hypoxia in the vascular wall and the kidney. This may be an adaptive response providing protection against organ damage. We investigated the hypothesis that ADM has a nephroprotective effect in two prospective cohorts of patients with type 2 diabetes recruited in France. The highest tertile of plasma MR-proADM (a surrogate for ADM) concentration at baseline was associated with the risk of renal outcomes (doubling of plasma creatinine concentration and/or progression to end-stage renal disease) during follow-up in both cohorts. Four SNPs in the ADM gene region were associated with plasma MR-proADM concentration at baseline and with eGFR during follow-up in both cohorts. The alleles associated with lower eGFR were also associated with lower plasma MR-proADM level. In conclusion, plasma MR-proADM concentration was associated with renal outcome in patients with type 2 diabetes. Our data suggest that the ADM gene modulates the genetic susceptibility to nephropathy progression. Results are consistent with the hypothesis of a reactive rise of ADM in diabetic nephropathy, blunted in risk alleles carriers, and with a nephroprotective effect of ADM. A possible therapeutic effect of ADM receptor agonists in diabetic renal disease would be worth investigating.

Prognostic significance of adrenomedullin in patients with heart failure and with myocardial infarction

We undertook this systematic review to determine the prognostic significance of adrenomedullin (ADM) in patients with heart failure and acute myocardial infarction (AMI). Given the difficulty in measuring mature ADM, its surrogate, midregional proadrenomedullin (MRproADM) has been used in most studies. Systematic search of original published studies through MEDLINE and the Cochrane Collaboration databases restricted to reports in English from January 1, 1993, to June 30, 2014, in humans was undertaken. Heterogeneity of studies prohibited a meta-analysis. In patients with heart failure, the area under the curve for prediction of mortality by MRproADM ranged from 0.68 to 0.81 (95% confidence intervals [CI] 0.63 to 0.91) across studies. One nmol/l increase in MRproADM was associated with hazard ratios (HRs) ranging from 1.77 to 2.79 (95% CI 1.29 to 5.95) for death in patients with heart failure. In patients with AMI, the area under the curve for MRproADM predicting MACE ranged from 0.64 to 0.80 (CI 0.51 to 0.87) across studies and death 0.79 to 0.84 (CI 0.73 to 0.90). One nmol/l increase in MRproADM was associated with HR for MACE ranging from 1.78 to 4.10 (CI 1.20 to 10.12), whereas log10 of MRproADM had HRs of 3.63 to 9.75 (CI 1.48 to 26.16) for MACE and 4.86 to 16.68 (CI 4.56 to 60.99) for death across studies in patients with AMI. In conclusion, adrenomedullin is an independent predictor of death in patients with heart failure and of MACE and death in patients who have suffered an AMI. Quantification of this peptide might contribute to improved risk stratification in settings of heart failure and myocardial infarction.

Adrenomedullin and arterial stiffness: integrative approach combining monocyte ADM expression, plasma MR-Pro-ADM, and genome-wide association study

BACKGROUND

Adrenomedullin (ADM) is a circulating vasoactive peptide involved in vascular homeostasis and endothelial function. Single nucleotide polymorphisms of the ADM gene are associated with blood pressure variability, and elevated levels of plasma midregional proadrenomedullin (MR-pro-ADM) are associated with cardiovascular diseases.

METHODS AND RESULTS

We investigated the sources of variability of ADM gene expression and plasma MR-pro-ADM concentrations in the general population, and their relationship with markers of atherosclerosis. MR-pro-ADM levels were assessed in 4155 individuals who underwent evaluation of carotid intima-media thickness and arterial rigidity (reflection index and stiffness index). In a subsample of 1372 individuals, ADM gene expression was assessed as part of a transcriptomic study of circulating monocytes. Nongenetic factors explained 45.8% and 7.5% of MR-pro-ADM and ADM expression variability, respectively. ADM expression correlated with plasma C-reactive protein, interleukin-receptor 1A, and myeloperoxidase, whereas MR-pro-ADM levels correlated with C-terminal proendothelin-1, creatinine, and N-terminal pro-B-type natriuretic peptide. Genome-wide association study of ADM expression and MR-pro-ADM levels both identified a single locus encompassing the ADM gene. ADM expression was associated with 1 single nucleotide polymorphism rs11042717 (P=2.36×10(-12)), whereas MR-pro-ADM was associated with 2 single nucleotide polymorphisms with additive effects, rs2957692 (P=1.54×10(-13)) and rs2957717 (P=4.24×10(-8)). Reflection index was independently associated with rs11042717 (P<10(-4)) and ADM expression (P=0.0002) but not with MR-pro-ADM. Weaker associations were observed for stiffness index. Intima-media thickness was not related to ADM single nucleotide polymorphisms or expression.

CONCLUSIONS

These results support an involvement of the ADM gene in the modulation of peripheral vascular tone.

Predictive value of midregional pro-adrenomedullin compared to natriuretic peptides for incident cardiovascular disease and heart failure in the population-based FINRISK 1997 cohort

INTRODUCTION

To examine whether midregional pro-adrenomedullin (MR-proADM) plasma concentrations predict incident cardiovascular outcomes in the general population. Natriuretic peptides (N-terminal pro-brain natriuretic peptide (NT-proBNP), B-type natriuretic peptide (BNP), and midregional pro-atrial natriuretic peptide (MR-proANP)) were analyzed for comparison.

MATERIAL AND METHODS

MR-proADM plasma concentrations and those of the natriuretic peptides were determined in 8444 individuals of the FINRISK 1997 cohort. Patients were followed for 14 years (median). Cox regression analyses, discrimination, and reclassification analyses adjusting for Framingham risk factors were performed to evaluate the additional benefit from MR-proADM.

RESULTS

MR-proADM concentrations significantly predicted all-cause death (hazard ratio highest quintile versus lowest 1.18, 95% confidence interval 1.08-1.28), stroke (1.20, 1.05-1.38), major adverse cardiac events (MACE) (1.27, 1.17-1.37), and heart failure (1.67, 1.49-1.87). MR-proADM remained associated with MACE, death, and heart failure even after additional adjustment for NT-proBNP and C-reactive protein. Adding MR-proADM to the Framingham risk factors significantly improved discrimination (P < 0.001 for C-statistics and integrated discrimination improvement) and risk reclassification for heart failure (net reclassification improvement 12.12%, P < 0.001).

CONCLUSIONS

In a healthy general population sample of the FINRISK 1997 cohort MR-proADM significantly predicted all-cause death, MACE, and especially heart failure even beyond NT- proBNP. It also improved risk reclassification for heart failure.

Serum copeptin and midregion proadrenomedullin (MR-proADM) after an ultramarathon

BACKGROUND

Although it is widely acknowledged that physical activity confers several health benefits, it remains uncertain whether strenuous and physically demanding exercise might determine biological effects that might turn to be ultimately unfavorable for health. Copeptin and midregion proadrenomedullin (MR-proADM) are emerging cardiovascular and stress biomarkers, but little is known about the influence of strenuous physical exercise on their concentrations.

METHODS

The present study was performed to investigate the variation of copeptin and MRproADM, along with that of serum creatinine and estimated glomerular filtration rate before and after a 60 km ultramarathon in 16 healthy Caucasian males.

RESULTS

The serum concentrations of both copeptin and MR-proADM remarkably increased after the 60 km run, by 6.4 times (interquartile range (IQR), 2.710.4) and 2.3 times (IQR, 1.8-2.6), respectively. A highly significant correlation was observed between the increase of creatinine and MR-proADM, but not between serum creatinine and copeptin. The percentage of subjects exhibiting values above the upper limit of the reference range in male was 0% for both copeptin and MR-proADM before the ultramarathon, but increased to respectively 81 and 63% postexercise.

CONCLUSION

The evidence that an ultramarathon causes a substantial increase of copeptin and MR-proADM raises doubts as to whether exhaustive exercise might be considered globally beneficial or even safe, especially in unfit or/and untrained population.

Association of multiple biomarkers and classical risk factors with early carotid atherosclerosis: results from the Gutenberg Health Study

BACKGROUND

In the Gutenberg Health Study, a random sample of the population was scanned with vascular ultrasound for early atherosclerosis. A continuous classical risk marker model (waist circumference, HbA1c, LDL/HDL ratio, pack years and pulse pressure) was compared to a model of modern biomarkers (C-reactive protein, troponin I, N-terminal pro B-type natriuretic peptide, copeptin, mid-regional pro-adrenomedullin, and asymmetric dimethylarginine) with regard to the ability of ruling out abnormal intima-media thickness (IMT), respectively, carotid plaques.

METHODS

Data of the first consecutive 5,000 participants (aged 35-74 years; 2,540 men, 2,460 women) were analyzed. IMT was measured at both common carotid arteries using an edge detection system. Plaques were defined as protrusion of ≥1.5 mm in common, internal and external carotid artery.

RESULTS

For classical risk factors, in comparison to a model of six modern biomarkers, regarding the variable (a) IMT>0.85 mm negative and positive predictive value (NPV and PPV) were 0.98 and 0.16 for both the classical risk factor model and the biomarker model. The second variable (b) presence of plaque could be ruled out with an NPV of 0.84 and identified with a PPV of 0.61 for classical risk factors, and 0.84 and 0.58 for biomarkers, respectively. Values were calculated using logistic regression analysis.

CONCLUSION

Classical risk factors allow ruling out pathologic IMT and presence of carotid plaques in a population of primary prevention in a reliable way. Modern biomarkers performed almost equally well but did not provide further information.

Midregional proadrenomedullin and its change predicts recurrent major coronary events and heart failure in stable coronary heart disease patients: the LIPID study

BACKGROUND

Biomarkers may contribute to risk stratification in coronary heart disease (CHD). We examined whether plasma midregional proadrenomedullin (MR-proADM) concentration at baseline and its change over one year predicts long-term outcomes in stable CHD patients.

METHODS

The LIPID study randomised patients 3-36 months after an acute coronary syndrome with total cholesterol 4.0-7.0 mmol/L (155-271 mg/dL), to placebo or pravastatin 40 mg. Follow-up was 6.0 years. MR-proADM plasma concentrations at baseline and one year later were determined in 7863 and 6658 patients, respectively. These were categorised into quartiles to perform Cox regression analysis, adjusting for baseline parameters.

RESULTS

Baseline MR-proADM concentrations predicted major CHD events (non-fatal myocardial infarction or CHD death; hazard ratio (HR) 1.52, 1.26-1.84 for Q4-Q1), CHD death (HR 2.21, 1.67-2.92), heart failure (HR 2.30, 1.78-2.97) and all-cause mortality (HR 1.82, 1.49-2.23). Associations were still significant after adjustment for baseline B-type natriuretic peptide (BNP) concentration. Increase in MR-proADM after one year was associated with increased risk of subsequent CHD events (HR 1.34, 1.08-1.66), non-fatal myocardial infarction (HR 1.50, 1.12-2.03), heart failure (HR 1.78, 1.37-2.30) and all-cause mortality (HR 1.31, 1.04-1.64). Associations with heart failure and all-cause mortality remained significant after adjusting for baseline and change in BNP concentration. Change in MR-proADM moderately improved risk reclassification for major CHD events (net reclassification improvement (NRI) 3.48%) but strongly improved risk reclassification for heart failure (NRI 5.60%).

CONCLUSIONS

Baseline and change in MR-proADM concentrations over one year are associated with risk of major clinical events, even after adjustment for BNP concentrations.

Midregional fragment of proadrenomedullin, new-onset albuminuria, and cardiovascular and all-cause mortality in patients with type 2 diabetes (ZODIAC-30)

OBJECTIVE

The midregional fragment of proadrenomedullin (MR-proADM) is a marker of endothelial dysfunction and has been associated with a variety of diseases. Our aim was to investigate whether MR-proADM is associated with new-onset albuminuria and cardiovascular (CV) and all-cause mortality in patients with type 2 diabetes treated in primary care.

RESEARCH DESIGN AND METHODS

Patients with type 2 diabetes participating in the observational Zwolle Outpatient Diabetes Project Integrating Available Care (ZODIAC) study were included. Cox regression analyses were used to assess the relation of baseline MR-proADM with new-onset albuminuria and CV and all-cause mortality. Risk prediction capabilities of MR-proADM for new-onset albuminuria and CV and all-cause mortality were assessed with Harrell's C and the integrated discrimination improvement.

RESULTS

In 1,243 patients (mean age 67 [±12] years), the median follow-up was 5.6 years (interquartile range 3.1-10.1); 388 (31%) patients died, with 168 (12%) CV deaths. Log2 MR-proADM was associated with CV (hazard ratio 1.96 [95% CI 1.27-3.01]) and all-cause mortality (1.78 [1.34-2.36]) after adjusting for age, sex, BMI, smoking, systolic blood pressure, cholesterol-to-HDL ratio, duration of diabetes, HbA1c, ACE inhibitor/angiotensin receptor blocker, history of CV diseases, log serum creatinine, and log albumin-to-creatinine ratio. MR-proADM slightly improved mortality risk prediction. The age- and sex-adjusted, but not multivariate-adjusted, MR-proADM levels were associated with new-onset albuminuria.

CONCLUSIONS

MR-proADM was associated with CV and all-cause mortality in patients with type 2 diabetes after a median follow-up of 5.6 years. There was no independent relationship with new-onset albuminuria. In the availability of an extensive set of risk factors, there was little added effect of MR-proADM in risk prediction of CV and all-cause mortality.

Effects of acute exercise and xanthine oxidase inhibition on novel cardiovascular biomarkers

Several sports have been associated with a postexercise increase of cardiac, liver, and skeletal muscle biomarkers of injury. Exhaustive or acute physical exercise causes an increased generation of reactive oxygen species, resulting in cellular injury. Thus, exercise and training may trigger pathophysiological changes in serum concentrations of a variety of biomarkers. In this study, we aimed to evaluate the variation of novel biomarkers of stress and cardiovascular disease such as copeptin, midregional part of proadrenomedullin (MR-proADM), growth differentiation factor 15 (GDF15), soluble vascular endothelial growth factor receptor, and placental growth factor along with uric acid before and after acute high-intensity exercise and allopurinol administration. We also assessed whether allopurinol administration may affect the circulating levels of these biomarkers by inhibition of XO activity. This is a double-blind, placebo-controlled study in which 12 professional football players were divided into 2 experimental groups. An oral dose of 300 mg of allopurinol was administered to one group of six participants 4 hours before a match of the Spanish Football League, whereas the other 6 participants received placebo (cellulose). Venous blood samples were obtained before the match (baseline) and twelve hours afterwards (post-match). Serum MR-proADM levels increased significantly in the placebo group, whereas serum GDF15 levels increased significantly in both the placebo and allopurinol group after the match. No differences in the other parameters tested were found after the match in any experimental group. The trend toward postexercise increase of serum MR-proADM and GDF15 levels shows that the metabolism of these proteins is clearly imbalanced after exercise, which thereby represents a potential source of biological variability in their clinical assessment.

Increased plasma levels of intermedin and brain natriuretic peptide associated with severity of coronary stenosis in acute coronary syndrome

Intermedin (IMD) is a newly discovered peptide with increased levels in plasma and cardiac tissue in mice with ischemia/reperfusion. Continuous administration of low dose IMD markedly elevated the mRNA abundance of myocardial BNP in rats. Plasma BNP levels may reflect the severity of degree of coronary stenosis in patients with acute coronary syndrome (ACS). However, the role of circulating IMD in coronary heart disease remains unclear. We aimed to examine the plasma content of IMD and brain natriuretic peptide (BNP) and its clinical significance in patients with ACS. We collected plasma samples from 41 patients with ACS and 31 controls and measured IMD and BNP levels by radioimmunoassay. The severity of coronary artery stenosis for patients with ACS was measured by coronary angiography. Plasma IMD and BNP levels were markedly higher in ACS patients than that in controls (P<0.05). The increased plasma IMD and BNP were positively correlated with degree of coronary stenosis in ACS patients (r=0.263 and r=0.238, respectively, both P<0.05). In addition, plasma levels of IMD were positively correlated with BNP levels.

Association of MR-proadrenomedullin with cardiovascular risk factors and subclinical cardiovascular disease

AIMS AND BACKGROUND

Midregional proadrenomedullin (MR-proADM) is a protein, which exerts various effects on the cardiovascular system. Recent studies underscored its prognostic implications in patients with acute dyspnea and cardiovascular diseases. Therefore, we aimed to determine the distribution of MR-proADM in the general population and to reveal potential associations of MR-proADM with cardiovascular risk factors and measures of subclinical cardiovascular disease.

METHODS AND RESULTS

MR-proADM plasma concentrations were determined in individuals of the population-based cohort of the Gutenberg Health Study (N = 5000) using a commercially available fluoroimmunoassay. Individuals were enrolled between April 2007 and October 2008. Subclinical cardiovascular disease was assessed using echocardiographic and functional measures of myocardial and vascular function. The mean age of the study population was 55.5 ± 10.9 years. In the overall population we determined a median MR-proADM plasma concentration of 0.44 nmol/L in men and women. MR-proADM concentrations were elevated in individuals with hypertension, diabetes, dyslipidemia, known cardiovascular disease, heart failure, peripheral artery disease, atrial fibrillation, and history of myocardial infarction and stroke. In men, we observed a positive association of MR-proADM with reduced ejection fraction, intraventricular septal diameter, wall thickness, and echocardiographic measures of diastolic dysfunction.

CONCLUSIONS

In this study, we present age-dependent reference values for MR-proADM in a representative population sample. Elevated MR-proADM plasma concentrations were strongly associated with classical cardiovascular risk factors and manifest cardiovascular diseases. Furthermore, we revealed a gender-specific association with echocardiographic measures of hypertension. MR-proADM seems to be a promising prognostic biomarker for subclinical and manifest cardiovascular disease.

Rapid response team-triggered procalcitonin measurement predicts infectious intensive care unit transfers*

OBJECTIVE

Determine if procalcitonin at the time of initial rapid response team activation identifies patients who are likely to need subsequent intensive care unit transfer.

DESIGN

Prospective observational cohort study.

SETTING

Urban, tertiary care hospital with rapid response team activation through an electronic modified early warning score.

PATIENTS

One hundred nineteen oncology and 100 consecutive non-oncology patients after initial rapid response team visit precipitated by an elevated electronic modified early warning score were recruited. Rapid response team activations by request of nursing or for other reasons were not studied. Five oncology patients seen by a rapid response team for complications of interleukin-2 therapeutic infusions were subsequently excluded.

INTERVENTIONS

Residual serum from the next ordered clinical test (within 12 hrs) was retrieved, frozen, and stored for procalcitonin determination. A second sample 12-24 hrs after the initial specimen was also retrieved if available and if the patient had not yet been transferred to the intensive care unit.

MEASUREMENTS AND MAIN RESULTS

Seventy-three patients (33%) were transferred to the intensive care unit. Rapid response team activations that did not result in intensive care unit transfer had significantly lower procalcitonin levels (median 0.28 ng/mL [interquartile range 0.09-1.24]) than those that resulted in intensive care unit transfer (median 0.51 ng/mL [interquartile range 0.11-1.97], p = .0001) but the area under the receiver operating curve was only 0.656. The change in procalcitonin level in patients with intensive care unit transfers was very heterogeneous but was significantly increased compared to the change in patients not transferred to the intensive care unit. Procalcitonin levels for intensive care unit transfers for probable or definite infection were 2.28 ng/mL [interquartile range 0.68-8.05], and were significantly greater than rapid response team visits that did not result in transfer (p = .0001). The difference between infectious and noninfectious intensive care unit transfers (0.95 ng/mL [interquartile range 0.26-1.89]) was also significant (p = .03). The procalcitonin levels of patients with noninfectious intensive care unit transfers were also different than the levels of patients who never transferred (p = .04).

CONCLUSIONS

Preliminary results suggest procalcitonin levels in patients at the time of initial visit by a rapid response team correlate with the need for subsequent intensive care unit transfer, particularly for infectious reasons.

New directions in cardiovascular risk assessment: the role of secondary risk stratification markers

Cardiovascular disease (CVD) risk screening is performed by multivariate methods relying on calculators derived from the Framingham study, other epidemiological studies or primary care records. However, it only identifies 70% of individuals at risk for CVD events and there has been interest in adding other risk factors to improve its predictive capacity. The addition of a family history of premature CVD is well established and there is evidence for adding lipoprotein (a) in some populations and possibly C-reactive protein may be suitable for general use in CVD risk assessment. Most new biochemical and imaging markers have been assessed in the context of improving risk classification in intermediate-risk groups rather than in the general population. There is evidence that N-terminal pro-B-type natriuretic peptide and coronary artery calcium score add significantly to risk prediction. The data for carotid intima-media thickness, ankle-brachial index are less strong and high sensitivity troponins look promising, but have had only limited data to date. Large scale meta-analyses ideally of pooled primary patient data will be required to determine the best additional markers to add to conventional risk prediction and in what groups to apply them.