Blood levels of copeptin on admission predict outcomes in out-of-hospital cardiac arrest survivors treated with therapeutic hypothermia

Risk assessment of sepsis through measurement of proAVP (copeptin): a secondary analysis of the TRIAGE study

OBJECTIVE

Systemic infections and sepsis lead to strong activation of the vasopressin system, which is pivotal for stimulation of the endocrine stress response and, in addition, has vasoconstrictive and immunomodulatory effects. Our aim was to assess the significance of the vasopressor system through measurement of C-terminal proAVP (copeptin) regarding mortality prediction in a large prospective cohort of patients with systemic infection.

DESIGN AND METHODS

This secondary analysis of the observational cohort TRIAGE study included consecutive, adult, medical patients with an initial diagnosis of infection seeking emergency department care. We used multivariable regression analysis to assess associations of copeptin levels in addition to the Sequential Organ Failure Assessment (SOFA) score with 30-day mortality. Discrimination was assessed by calculation of the area under the curve (AUC).

RESULTS

Overall, 45 of 609 (7.4%) patients with infection died within 30 days. Non-survivors had a marked upregulation of the vasopressin system with a more than four-fold increase in admission copeptin levels compared to non-survivors (199.9 ± 204.7 vs 46.6 ± 77.2 pmol/L). In a statistical model, copeptin was significantly associated with mortality (adjusted odds ratio of 1.04, 95% CI 1.01 to 1.07, P = 0.002). Regarding discrimination, copeptin alone showed an AUC of 0.82, while adding copeptin to the SOFA score significantly improved its prognostic ability (AUC 0.83 vs 0.86, P = 0.027).

CONCLUSION

Activation of the vasopressin system mirrored by an increase in copeptin levels provided significant information regarding mortality risk and improved the SOFA score for prediction of sepsis mortality.

Copeptin as a Prognostic Marker in Prolonged Targeted Temperature Management After Out-of-Hospital Cardiac Arrest

The aim was to investigate blood concentrations of copeptin and the prognostication in 24 versus 48 hours of targeted temperature management (TTM) in patients resuscitated after out-of-hospital cardiac arrest. This is an exploratory biomarker substudy of the trial entitled; "Targeted temperature management for 48 vs 24 hours and neurologic outcome after out-of-hospital-cardiac-arrest: A randomized clinical trial." Patients were randomized to target temperature of 33°C ± 1°C for 24 (TTM24) or 48 (TTM48) hours. The primary outcome was copeptin concentrations compared with TTM at admission, 24, 48, and 72 hours (t24, t48, and t72) after reaching target temperature. Secondary outcomes were the association between copeptin and cerebral performance category (CPC) score after 6 months, and copeptin level between cerebral or noncerebral causes of death. Blood samples from 117 patients were analyzed from two Scandinavian sites. No significant differences in copeptin concentrations were found between TTM24 versus TTM48 at admission 211.3 μg/L (148-276.6) versus 179.8 μg/L (127-232.6) (p = 0.45), t24: 23.3 μg/L (16.5-30.2) versus 18.6 μg/L (13.3-23.9) (p = 0.25), t48: 28.8 μg/L (20.6-36.9) versus 19.7 μg/L (14.3-25.1) (p = 0.06), and t72: 23.3 μg/L (13.8-26.8) versus 31.6 μg/L (22-41.2) (p = 0.05). Copeptin concentrations were significantly higher in poor neurological outcome group at t24, t48, and t72 (p < 0.01), but not at admission (p = 0.19). The prognostic ability of copeptin (area under the receiver operating characteristic curve) was at admission: 0.59 (95% confidence intervals: 0.46-0.72), t24: 0.74 (0.63-0.86), t48: 0.8 (0.7-0.9), and t72: 0.76 (0.65-0.87). Copeptin levels were not significantly different in noncerebral compared with cerebral causes at admission: p = 0.41, t24: p = 0.52, t48: p = 0.15, and t72: p = 0.38. There were no differences in the level of copeptin in TTM24 versus TTM48. Blood concentrations of copeptin were associated with CPC at 6 months, and no association between levels of copeptin and cerebral versus noncerebral causes of death was observed.

Copeptin as a marker of outcome after cardiac arrest: a sub-study of the TTM trial

Background

Arginine vasopressin has complex actions in critically ill patients, involving vasoregulatory status, plasma volume, and cortisol levels. Copeptin, a surrogate marker for arginine vasopressin, has shown promising prognostic features in small observational studies and is used clinically for early rule out of acute coronary syndrome. The objective of this study was to explore the association between early measurements of copeptin, circulatory status, and short-term survival after out-of-hospital cardiac arrest.

Methods

Serial blood samples were collected at 24, 48, and 72 h as part of the target temperature management at 33 °C versus 36 °C after cardiac arrest trial, an international multicenter randomized trial where unconscious survivors after out-of-hospital cardiac arrest were allocated to an intervention of 33 or 36 °C for 24 h. Primary outcome was 30-day survival with secondary endpoints circulatory cause of death and cardiovascular deterioration composite; in addition, we examined the correlation with extended the cardiovascular sequential organ failure assessment (eCvSOFA) score.

Results

Six hundred ninety patients were included in the analyses, of whom 203 (30.3%) developed cardiovascular deterioration within 24 h, and 273 (39.6%) died within 30 days. Copeptin measured at 24 h was found to be independently associated with 30-day survival, hazard ratio 1.17 [1.06–1.28], p = 0.001; circulatory cause of death, odds ratio 1.03 [1.01–1.04], p = 0.001; and cardiovascular deterioration composite, odds ratio of 1.05 [1.02–1.08], p < 0.001. Copeptin at 24 h was correlated with eCvSOFA score with rho 0.19 [0.12–0.27], p < 0.001.

Conclusion

Copeptin is an independent marker of severity of the post cardiac arrest syndrome, partially related to circulatory failure.

Trial registration

Clinical Trials, NCT01020916. Registered November 26, 2009.

Prognostic Impact of Serum Albumin Concentration for Neurologically Favorable Outcome in Patients Treated with Targeted Temperature Management After Out-of-Hospital Cardiac Arrest: A Multicenter Prospective Study

To assess whether serum albumin concentration measured upon hospital arrival was useful as an early prognostic biomarker for neurologically favorable outcome in out-of-hospital cardiac arrest (OHCA) patients treated with target temperature management (TTM). This prospective, multicenter observational study (The CRITICAL Study) carried out between July 1, 2012 and December 31, 2014 in Osaka Prefecture, Japan involving 13 critical care medical centers (CCMCs) and one non-CCMC with an emergency department. This study included patients ≥18 years of age who underwent an OHCA, for whom resuscitation was attempted by Emergency Medical Services personnel and were then transported to participating institutions, and who were then treated with TTM. Based on the serum albumin concentration upon hospital arrival, involved patients were divided into four quartiles (Q1-Q4) defined as Q1 (<3.0 g/dL), Q2 (≥3.0, <3.4 g/dL), Q3 (≥3.4, <3.8 g/dL), and Q4 (≥3.8 g/dL). The primary outcome of this study was 1-month survival with neurologically favorable outcome defined by cerebral performance category 1 or 2. During the study period, a total of 327 were eligible for our analysis. The overall proportion of neurologically favorable outcome was 33.0% (108/327). The Q4 group had the highest proportion of neurologically favorable outcome (52.5% [48/91]), followed by Q3 (34.5% [30/87]), Q2 (27.3% [21/77]), and Q1 (12.5% [9/72]). The multivariable logistic regression analysis demonstrated that the proportion of neurologically favorable outcome was significantly higher in the Q4 group than that in the Q1 group (adjusted odds ratio 10.39; 95% confidence interval 3.36-32.17). The adjusted proportion of neurologically favorable outcome increased in a stepwise fashion across increasing quartiles (p < 0.001). In this study, higher serum albumin concentration upon hospital arrival had a positive association with neurologically favorable outcome after OHCA in a dose-dependent manner.

Prognostic utility of neuroinjury biomarkers in post out-of-hospital cardiac arrest (OHCA) patient management

Despite aggressive intervention, patients who survive an out-of-hospital cardiac arrest (OHCA) generally have very poor prognoses, with nationwide survival rates of approximately 10-20%. Approximately 90% of survivors will have moderate to severe neurological injury ranging from moderate cognitive impairment to brain death. Currently, few early prognostic indicators are considered reliable enough to support patients' families and clinicians' in their decisions regarding medical futility. Blood biomarkers of neurological injury after OHCA may be of prognostic value in these cases. When most bodily tissues are oxygen-deprived, cellular metabolism switches from aerobic to anaerobic respiration. Neurons are a notable exception, however, being dependent solely upon aerobic respiration. Thus, after several minutes without circulating oxygen, neurons sustain irreversible damage, and certain measurable biomarkers are released into the circulation. Prior studies have demonstrated value in blood biomarkers in prediction of survival and neurologic impairment after OHCA. We hypothesize that understanding peptide biomarker kinetics in the early return of spontaneous circulation (ROSC) period, especially in the setting of refractory cardiac arrest, may assist clinicians in determining prognosis earlier in acute resuscitation. Specifically, during and after immediate resuscitation and return of ROSC, clinicians and families face a series of important questions regarding patient prognosis, futility of care and allocation of scarce resources such as the early initiation of extracorporeal cardiopulmonary resuscitation (ECPR). The ability to provide early prognostic information in this setting is highly valuable. Currently available, as well as potential biomarkers that could be good candidates in prognostication of neurological outcomes after OHCA or in the setting of refractory cardiac arrest will be reviewed and discussed.

Biomarkers from distinct biological pathways improve early risk stratification in medical emergency patients: the multinational, prospective, observational TRIAGE study

INTRODUCTION

Early risk stratification in the emergency department (ED) is vital to reduce time to effective treatment in high-risk patients and to improve patient flow. Yet, there is a lack of investigations evaluating the incremental usefulness of multiple biomarkers measured upon admission from distinct biological pathways for predicting fatal outcome and high initial treatment urgency in unselected ED patients in a multicenter and multinational setting.

METHOD

We included consecutive, adult, medical patients seeking ED care into this observational, cohort study in Switzerland, France and the USA. We recorded initial clinical parameters and batch-measured prognostic biomarkers of inflammation (pro-adrenomedullin [ProADM]), stress (copeptin) and infection (procalcitonin).

RESULTS

During a 30-day follow-up, 331 of 7132 (4.6 %) participants reached the primary endpoint of death within 30 days. In logistic regression models adjusted for conventional risk factors available at ED admission, all three biomarkers strongly predicted the risk of death (AUC 0.83, 0.78 and 0.75), ICU admission (AUC 0.67, 0.69 and 0.62) and high initial triage priority (0.67, 0.66 and 0.58). For the prediction of death, ProADM significantly improved regression models including (a) clinical information available at ED admission (AUC increase from 0.79 to 0.84), (b) full clinical information at ED discharge (AUC increase from 0.85 to 0.88), and (c) triage information (AUC increase from 0.67 to 0.83) (p <0.01 for each comparison). Similarly, ProADM also improved clinical models for prediction of ICU admission and high initial treatment urgency. Results were robust in regard to predefined patient subgroups by center, main diagnosis, presenting symptoms, age and gender.

CONCLUSIONS

Combination of clinical information with results of blood biomarkers measured upon ED admission allows early and more adequate risk stratification in individual unselected medical ED patients. A randomized trial is needed to answer the question whether biomarker-guided initial patient triage reduces time to initial treatment of high-risk patients in the ED and thereby improves patient flow and clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01768494 . Registered January 9, 2013.

Copeptin as a biomarker in heart failure

Increased neurohormonal activation is a key feature of heart failure (HF). Copeptin is a surrogate marker for proarginine vasopressin and the prognostic value of copeptin has been reported for multiple disease states of both nonvascular and cardiovascular etiology. Elevated plasma copeptin in HF has been associated with adverse outcomes such as increased mortality, risk of hospitalization and correlates with the severity of HF. Copeptin may add prognostic information to already established predictors such as clinical variables and natriuretic peptides in HF. In addition, copeptin has been found to be a superior marker when compared with BNP and NT-proBNP in HF patients discharged after hospitalization caused by HF or myocardial infarction (MI). The optimal use of copeptin in HF remains unresolved and future appropriately sized and randomized trials must determine the role of copeptin in HF as a marker of adverse outcomes, risk stratification or as a target in biomarker-guided therapy with arginine vasopressin-antagonists in individualized patient treatment and everyday clinical practice.

Copeptin testing in acute myocardial infarction: ready for routine use?

Suspected acute myocardial infarction is one of the leading causes of admission to emergency departments. In the last decade, biomarkers revolutionized the management of patients with suspected acute coronary syndromes. Besides their pivotal assistance in timely diagnosis, biomarkers provide additional information for risk stratification. Cardiac troponins I and T are the most sensitive and specific markers of acute myocardial injury. Nonetheless, in order to overcome the remaining limitations of these markers, novel candidate biomarkers sensitive to early stage of disease are being extensively investigated. Among them, copeptin, a stable peptide derived from the precursor of vasopressin, emerged as a promising biomarker for the evaluation of suspected acute myocardial infarction. In this review, we summarize the currently available evidence for the usefulness of copeptin in the diagnosis and risk stratification of patients with suspected acute myocardial infarction in comparison with routine biomarkers.

Copeptin levels are associated with organ dysfunction and death in the intensive care unit after out-of-hospital cardiac arrest

Introduction

We studied associations of the stress hormones copeptin and cortisol with outcome and organ dysfunction after out-of-hospital cardiac arrest (OHCA).

Methods

Plasma was obtained after consent from next of kin in the FINNRESUSCI study conducted in 21 Finnish intensive care units (ICUs) between 2010 and 2011. We measured plasma copeptin (pmol/L) and free cortisol (nmol/L) on ICU admission (245 patients) and at 48 hours (additional 33 patients). Organ dysfunction was categorised with 24-hour Sequential Organ Failure Assessment (SOFA) scores. Twelve-month neurological outcome (available in 276 patients) was classified with cerebral performance categories (CPC) and dichotomised into good (CPC 1 or 2) or poor (CPC 3 to 5). Data are presented as medians and interquartile ranges (IQRs). A Mann–Whitney U test, multiple linear and logistic regression tests with odds ratios (ORs) 95% confidence intervals (CIs) and beta (B) values, repeated measure analysis of variance, and receiver operating characteristic curves with area under the curve (AUC) were performed.

Results

Patients with a poor 12-month outcome had higher levels of admission copeptin (89, IQR 41 to 193 versus 51, IQR 29 to 111 pmol/L, P = 0.0014) and cortisol (728, IQR 522 to 1,017 versus 576, IQR 355 to 850 nmol/L, P = 0.0013). Copeptin levels fell between admission and 48 hours (P <0.001), independently of outcome (P = 0.847). Cortisol levels did not change between admission and 48 hours (P = 0.313), independently of outcome (P = 0.221). The AUC for predicting long-term outcome was weak for copeptin (0.62, 95% CI 0.55 to 0.69) and cortisol (0.62, 95% CI 0.54 to 0.69). With logistic regression, admission copeptin (standard deviation (SD) increase OR 1.4, 95% CI 1.03 to 1.98) and cortisol (SD increase OR 1.5, 95% CI 1.1 to 2.0) predicted ICU mortality but not 12-month outcome. Admission factors correlating with SOFA were shockable rhythm (B −1.3, 95% CI −2.2 to −0.5), adrenaline use (B 1.1, 95% CI 0.2 to 2.0), therapeutic hypothermia (B 1.3 95% CI 0.4-2.2), and copeptin (B 0.04, 95% CI 0.02 to 0.07).

Conclusions

Admission copeptin and free cortisol were not of prognostic value regarding 12-month neurological outcome after OHCA. Higher admission copeptin and cortisol were associated with ICU death, and copeptin predicted subsequent organ dysfunction.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0831-y) contains supplementary material, which is available to authorized users.

Risk stratification in emergency patients by copeptin

BACKGROUND

Rapid risk stratification is a core task in emergency medicine. Identifying patients at high and low risk shortly after admission could help clinical decision-making regarding treatment, level of observation, allocation of resources and post discharge follow-up. The purpose of the present study was to determine short-, mid- and long-term mortality by plasma measurement of copeptin in unselected admitted patients.

METHOD

Consecutive patients >40-years-old admitted to an inner-city hospital were included. Within the first 24 hours after admission, a structured medical interview was conducted and self-reported medical history was recorded. All patients underwent a clinical examination, an echocardiographic evaluation and collection of blood for later measurement of risk markers.

RESULTS

Plasma for copeptin measurement was available from 1,320 patients (average age 70.5 years, 59.4% women). Median follow-up time was 11.5 years (range 11.0 to 12.0 years). Copeptin was elevated (that is, above the 97.5 percentile in healthy individuals).Mortality within the first week was 2.7% (17/627) for patients with elevated copeptin (above the 97.5 percentile, that is, >11.3 pmol/L) compared to 0.1% (1/693) for patients with normal copeptin concentrations (that is, ≤11.3 pmol/L) (P <0.01). Three-month mortality was 14.5% (91/627) for patients with elevated copeptin compared to 3.2% (22/693) for patients with normal copeptin. Similar figures for one-year mortality and for the entire observation period were 27.6% (173/627) versus 8.7% (60/693) and 82.9% (520/527) versus 57.5% (398/693) (P <0.01 for both), respectively.Using multivariable Cox regression analyses shows that elevated copeptin was significantly and independently related to short-, mid- and long-term mortality. Adjusted hazard ratios were 2.4 for three-month mortality, 1.9 for one-year mortality and 1.4 for mortality in the entire observation period.

CONCLUSIONS

In patients admitted to an inner-city hospital, copeptin was strongly associated with short-, mid- and long-term mortality. The results suggest that rapid copeptin measurement could be a useful tool for both disposition in an emergency department and for mid- and long-term risk assessment.

CT-proAVP (copeptin), MR-proANP and Peroxiredoxin 4 after cardiac arrest: release profiles and correlation to outcome

BACKGROUND

Further characterization of the post-cardiac arrest syndrome (PCAS) is essential to better understand the mechanisms resulting in injury and death. We investigated serial serum concentrations of the stress hormone c-terminal provasopressin (CT-proAVP or copeptin), the cardiac biomarker MR-proANP and a biomarker of oxidation injury, Peroxiredoxin 4 (Prx4) in patients treated with mild hypothermia (MHT) after cardiac arrest, and studied their association to the PCAS and long-term outcome.

METHODS

Serum samples from cardiac arrest patients were collected serially: at admission, 2, 6, 12, 24, 36, 48 and 72 h after cardiac arrest. CT-proAVP, MR-proANP and Prx4 concentrations were determined and tested for association with two surrogate markers of PCAS (time to return of spontaneous circulation and circulation-SOFA score) and with cerebral performance category (CPC) at 6 months. Good outcome was defined as CPC 1 to 2.

RESULTS

Eighty-four patients were included. CT-proAVP, MR-proANP and Prx4 were early biomarkers with maximum concentrations soon after cardiac arrest and with a significant discriminatory ability between good and poor long-term outcome at most time points. CT-proAVP predicted a poor outcome with the highest accuracy, followed by MR-proANP and Prx4 (area under the receiving operating characteristics curve at 12 h of 0.85, 0.77 and 0.76 respectively). CT-proAVP and MR-proANP showed best correlation to the PCAS.

CONCLUSION

In 84 resuscitated patients receiving MHT after cardiac arrest, there is a significant difference in concentrations of CT-proAVP, MR-proANP and Prx4 between patients with good and poor outcome. CT-proAVP and MR-proANP have a significant correlation to surrogate markers of the PCAS.

How to assess prognosis after cardiac arrest and therapeutic hypothermia

The prognosis of patients who are admitted in a comatose state following successful resuscitation after cardiac arrest remains uncertain. Although the introduction of therapeutic hypothermia (TH) and improvements in post-resuscitation care have significantly increased the number of patients who are discharged home with minimal brain damage, short-term assessment of neurological outcome remains a challenge. The need for early and accurate prognostic predictors is crucial, especially since sedation and TH may alter the neurological examination and delay the recovery of motor response for several days. The development of additional tools, including electrophysiological examinations (electroencephalography and somatosensory evoked potentials), neuroimaging and chemical biomarkers, may help to evaluate the extent of brain injury in these patients. Given the extensive literature existing on this topic and the confounding effects of TH on the strength of these tools in outcome prognostication after cardiac arrest, the aim of this narrative review is to provide a practical approach to post-anoxic brain injury when TH is used. We also discuss when and how these tools could be combined with the neurological examination in a multimodal approach to improve outcome prediction in this population.