Troponin T is a strong marker of mortality in hospitalized patients

Develop ment and validation of a prognostic dynamic nomogram for in-hospital mortality in patients with Stanford type B aortic dissection

Background

This study aimed to identify the risk factors for in-hospital mortality in patients with Stanford type B aortic dissection (TBAD) and develop and validate a prognostic dynamic nomogram for in-hospital mortality in these patients.

Methods

This retrospective study involved patients with TBAD treated from April 2002 to December 2020 at the General Hospital of Northern Theater Command. The patients with TBAD were divided into survival and non-survival groups. The data were analyzed by univariate and multivariate logistic regression analyses. To identify independent risk factors for in-hospital mortality, multivariate logistic regression analysis, least absolute shrinkage, and selection operator regression were used. A prediction model was constructed using a nomogram based on these factors and validated using the original data set. To assess its discriminative ability, the area under the receiver operating characteristic curve (AUC) was calculated, and the calibration ability was tested using a calibration curve and the Hosmer-Lemeshow test. Clinical utility was evaluated using decision curve analysis (DCA) and clinical impact curves (CIC).

Results

Of the 978 included patients, 52 (5.3%) died in hospital. The following variables helped predict in-hospital mortality: pleural effusion, systolic blood pressure ≥160 mmHg, heart rate >100 bpm, anemia, ischemic cerebrovascular disease, abnormal cTnT level, and estimated glomerular filtration rate <60 ml/min. The prediction model demonstrated good discrimination [AUC = 0.894; 95% confidence interval (CI), 0.850-0.938]. The predicted probabilities of in-hospital death corresponded well to the actual prevalence rate [calibration curve: via 1,000 bootstrap resamples, a bootstrap-corrected Harrell's concordance index of 0.905 (95% CI, 0.865-0.945), and the Hosmer-Lemeshow test (χ² = 8.3334, P = 0.4016)]. DCA indicated that when the risk threshold was set between 0.04 and 0.88, the predictive model could achieve larger clinical net benefits than "no intervention" or "intervention for all" options. Moreover, CIC showed good predictive ability and clinical utility for the model.

Conclusion

We developed and validated prediction nomograms, including a simple bed nomogram and online dynamic nomogram, that could be used to identify patients with TBAD at higher risk of in-hospital mortality, thereby better enabling clinicians to provide individualized patient management and timely and effective interventions.

Coronavirus Disease 2019 (COVID-19) and its implications for cardiovascular care: expert document from the German Cardiac Society and the World Heart Federation

Coronavirus diseases 2019 (COVID-19) has become a worldwide pandemic affecting people at high risk and particularly at advanced age, cardiovascular and pulmonary disease. As cardiovascular patients are at high risk but also have dyspnea and fatigue as leading symptoms, prevention, diagnostics and treatment in these patients are important to provide adequate care for those with or without COVID-19 but most importantly when comorbid cardiovascular conditions are present. Severe COVID-19 with acute respiratory distress (ARDS) is challenging as patients with elevated myocardial markers such as troponin are at enhanced high risk for fatal outcomes. As angiotensin-converting enzyme 2 (ACE2) is regarded as the viral receptor for cell entry and as the Coronavirus is downregulating this enzyme, which provides cardiovascular and pulmonary protection, there is ongoing discussions on whether treatment with cardiovascular drugs, which upregulate the viral receptor ACE2 should be modified. As most of the COVID-19 patients have cardiovascular comorbidities like hypertension, diabetes, coronary artery disease and heart failure, which imposes a high risk on these patients, cardiovascular therapy should not be modified or even withdrawn. As cardiac injury is a common feature of COVID-19 associated ARDS and is linked with poor outcomes, swift diagnostic management and specialist care of cardiovascular patients in the area of COVID-19 is of particular importance and deserves special attention.

Comparison of prognostic values of high-sensitivity cardiac troponin T and N-terminal prohormone brain natriuretic peptide to assess mortality in elderly inpatients

BACKGROUND

Studies have shown that increases in low-level high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal prohormone brain natriuretic peptide (NT-proBNP) in the elderly population lead to high risk of adverse clinical outcomes, such as mortality. In this study, associations between the two biomarkers and long-term mortality in elderly patients hospitalized for medical conditions other than acute cardiovascular events were investigated. A comparison of the predictive value of hs-cTnT and NT-proBNP for all-cause mortality was conducted.

METHODS

A cohort of 715 elderly inpatients free of acute cardiovascular events was initially recruited. Based on tertiles of baseline hs-cTnT and NT-proBNP levels, the elderly were arranged into low, middle, and high groups. The mortality of each group was observed and the predictive values of hs-cTnT and NT-proBNP compared. Additionally, all-cause mortality was analyzed for hs-cTnT and NT-proBNP combined.

RESULTS

There were 135 (18.9%) all-cause mortality cases identified during follow-up (median 47 months). The upper tertile of hs-cTnT was significantly associated with an increased risk of mortality (HR 3.29, 95% CI 1.85-5.85), even after adjustment for potential confounders. However, there were no significant differences observed in mortality rates among the three NT-proBNP groups after adjustment for potential confounders (HR 1.77, 95% CI 0.83-3.17). Compared to NT-proBNP, hs-cTnT was a better predictor of mortality, as area under curves for hs-cTnT and NT-proBNP at 60 months were 0.712 (95% CI 0.616-0.809) and 0.585 (95% CI 0.483-0.6871), respectively. Also, the combination of the two cardiac biomarkers did not render a better predictive value for mortality than hs-cTnT alone.

CONCLUSION

Unlike hs-cTnT, baseline NT-proBNP levels failed to show an independent association with all-cause mortality in hospitalized elderly without acute cardiovascular events. hs-cTnT provided significant prognostic value for mortality in the study cohort.

Relationship between high-sensitivity cardiac troponin T and the prognosis of elderly inpatients with non-acute coronary syndromes

Objective

Low-level high-sensitivity cardiac troponin T (hs-cTnT) increases in elderly population. In this study, the relationship between hs-cTnT level and all-cause death of elderly inpatients with non-acute coronary syndrome (non-ACS) after discharge from the hospital was investigated.

Materials and methods

Non-ACS patients aged >65 years admitted in the General Practice Wards and Department of Geriatrics of Fuxing Hospital Affiliated to Capital Medical University were enrolled in the study. The patients were grouped according to the tertiles of hs-cTnT levels. Biochemical markers, hs-cTnT, and amino-terminal pro-brain natriuretic peptide were measured. The median follow-up period was 47 months, and all-cause deaths of the patients were observed.

Results

A total of 722 patients, including 473 males and 249 females, aged 65-98 (82.43±5.98) years were enrolled in the study. The level of hs-cTnT was found to be higher in males, and increased with age and comorbidities (P<0.01). Compared with low-level group, NT-proBNP level of patients in high-level group was higher, while hemoglobin (Hb), estimated glomerular filtration rate (eGFR), and left ventricular ejection fraction (LVEF) levels were lower (P<0.001). The mortality rate increased significantly with increased hs-cTnT levels (P<0.001). The total number of deaths was 136 (18.8%), and of these, 108 (79.4%) were noncardiac deaths. Risk of all-cause deaths in the highest hs-cTnT level group was 7.3 times higher than that of the lowest hs-cTnT level group (95% CI: 4.29-12.51, P<0.001). After adjusting for gender, age, comorbidities, NT-proBNP, Hb, eGFR, and LVEF, hs-cTnT level still affected the patient's survival time (HR: 3.01, 95% CI: 1.67-5.43, P<0.001).

Conclusion

These findings suggest that low-level hs-cTnT was increased in elderly inpatients without ACS. They further highlight that baseline hs-cTnT level was associated with increased risk of all-cause deaths among patients after their discharge, and most deaths were from non-cardiovascular diseases.

N-terminal pro-brain natriuretic peptide and associated factors in the general working population: a baseline survey of the Uranosaki cohort study

Few data on clinical characteristics associated with N-terminal pro-brain natriuretic peptide (NT-proBNP) or the clinical value of measuring NT-proBNP in the working population are available. The aim of the present study was to investigate the levels of NT-proBNP and their association with clinical variables in the Japanese general working population by using baseline data from the Uranosaki cohort study. In the study, the plasma concentration of NT-proBNP and some biomarkers were measured in addition to the standard health checkups at the workplace. Questionnaires regarding health-related quality of life (HR-QOL) were also completed. A total of 2140 participants were enrolled in the study. Plasma levels of NT-proBNP were positively associated with age, female sex, systolic blood pressure, pulse pressure, prevalent hypertension, smoking habit, high-density lipoprotein cholesterol (HDL-C), and prevalent proteinuria, and negatively associated with body mass index, lipid profiles except HDL-C, uric acid, renal function, and hemoglobin. Both the plasma concentration of high-molecular weight adiponectin and that of high-sensitivity troponin T were positively and independently associated with NT-proBNP. In addition, the HR-QOL score regarding sleep disorder was independently associated with NT-proBNP. Thus, we have obtained evidence that the plasma NT-proBNP is affected by several clinical variables in the general working population.

Prognostic Impact of Myocardial Injury Related to Various Cardiac and Noncardiac Conditions

BACKGROUND

Elevated cardiac troponins in clinical conditions other than myocardial infarction are well known. For such occurrences, the term "myocardial injury" has been proposed. The long-term outcome in patients with myocardial injury related to various cardiac and noncardiac clinical disorders is unknown.

METHODS

During January 2010 to January 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. Patients with cardiac troponin I values >30 ng/L and no evidence of myocardial ischemia were diagnosed as having myocardial injury. Patients were classified into 5 categories of plausible related conditions: cardiac ischemic, cardiac nonischemic, noncardiac, multifactorial, or indeterminate. Follow-up was a minimum of 3 years, with all-cause mortality as the single end-point.

RESULTS

A total of 3762 patients were considered, of whom 1089 (29%) had myocardial injury. The most common associated conditions were noncardiac (n = 346) or multifactorial (n = 359). Cardiac ischemic (n = 183) and cardiac nonischemic (n = 134) conditions occurred less frequently. After a median of 3.2 years, 645 patients (59%) had died. A multivariate Cox regression analysis showed no difference in mortality between patients with cardiac ischemic and cardiac nonischemic conditions (hazard ratio [HR] 0.75; 95% confidence interval [CI], 0.50-1.13; P = .2). Patients with noncardiac or multifactorial disorders, however, had significantly higher mortality than those with associated cardiac ischemic conditions (HR 1.39; 95% CI, 1.06-1.80; P = .02, and HR 1.94; 95% CI, 1.50-2.51; P <.001), respectively.

CONCLUSIONS

In patients with myocardial injury, the most common associated conditions were noncardiac or multifactorial. Of notice, these patients had significantly higher long-term mortality when compared with those with associated cardiac conditions.

Different Prognostic Significance of Cardiac Troponin at Presentation and Peak Cardiac Troponin in Patients with Non-ST Segment Elevation Myocardial Infarction

OBJECTIVES

Non-ST elevation myocardial infarction (NSTEMI) is one of the most common manifestations of acute coronary syndromes (ACS). We evaluated the prognostic role of cardiac troponin I (cTnI) at presentation and peak cardiac troponin I in patients with NSTEMI.

METHODS

We consecutively enrolled 215 subjects presenting with NSTEMI. Subjects were followed up for 1 year. cTnI at presentation and the peak value of cTnI were measured. The primary end point was defined as cardiovascular death, readmission to hospital with heart failure and new ACS.

RESULTS

The subjects who presented the primary end point (49 subjects) had significantly increased values of peak cTnI compared to subjects free of cardiovascular events [7.19 (2.97-21.32) vs. 4.09 (1.18-11.85) ng/l; p = 0.002]. Nevertheless, cTnI at presentation did not differ between subjects who presented the primary end point and those free of events (p = 0.39). Multivariate Cox regression analysis after adjustment for confounders revealed by the univariate analysis showed that for an increase in peak cTnI from 1 to 10 ng/l, there is a 60% anticipated increase in the relative risk to present the primary end point (p = 0.04).

CONCLUSION

These findings documented the different prognostic significance of cTnI at presentation and peak cTnI in patients presenting with NSTEMI, and highlighted the importance of monitoring the levels of cTnI in this high-risk population.

High-sensitivity cardiac troponin T: A biomarker for the early risk stratification of type-A acute aortic dissection?

BACKGROUND

High-sensitivity cardiac troponin is the most specific and sensitive biomarker of myocardial injury. However, no study has investigated whether the early concentration of high-sensitivity cardiac troponin is increased or is of value in predicting short-term prognosis in patients with type-A acute aortic dissection (AAD) in the emergency department.

AIMS

To measure the high-sensitivity cardiac troponin T (hs-TnT) concentration in patients with type-A AAD upon hospital admission, and to assess its value in predicting short-term prognosis.

METHODS

We enrolled consecutive patients with type-A AAD. Blood samples were collected on admission; hs-TnT concentrations were measured on the Elecsys 2010 system. High-sensitivity C-reactive protein (hs-CRP), D-dimer and other biochemical indicators were measured. Patients were divided into two groups according to hs-TnT concentration on admission (< or ≥0.014ng/mL).

RESULTS

More than half (61.2%) of the 103 included patients had an hs-TnT concentration ≥0.014ng/mL. hs-TnT concentrations were significantly higher in those who died compared with survivors (0.292±0.516 vs. 0.069±0.154ng/mL; P=0.003). Multivariable Cox regression analysis suggested that hs-TnT is an independent factor for predicting in-hospital mortality risk (odds ratio: 2.202, 95% confidence interval: 1.111-4.367; P=0.024). Kaplan-Meier curves revealed a significant increase in hospital mortality in the hs-TnT(+) group compared with the hs-TnT(-) group (P=0.021). When hs-TnT was ≥0.042ng/mL, the sensitivity and specificity in predicting hospital short-term mortality were 70.8% and 76.4%, respectively.

CONCLUSIONS

Our study suggests that hs-TnT concentration could be used as an early biomarker for the risk stratification of patients with type-A AAD in the emergency department; the relationship between hs-TnT concentration and long-term prognosis needs further investigation.

The formation and design of the TRIAGE study--baseline data on 6005 consecutive patients admitted to hospital from the emergency department

BACKGROUND

Patient crowding in emergency departments (ED) is a common challenge and associated with worsened outcome for the patients. Previous studies on biomarkers in the ED setting has focused on identification of high risk patients, and and the ability to use biomarkers to identify low-risk patients has only been sparsely examined. The broader aims of the TRIAGE study are to develop methods to identify low-risk patients appropriate for early ED discharge by combining information from a wide range of new inflammatory biomarkers and vital signs, the present baseline article aims to describe the formation of the TRIAGE database and characteristize the included patients.

METHODS

We included consecutive patients ≥ 17 years admitted to hospital after triage staging in the ED. Blood samples for a biobank were collected and plasma stored in a freezer (-80 °C). Triage was done by a trained nurse using the Danish Emergency Proces Triage (DEPT) which categorizes patients as green (not urgent), yellow (urgent), orange (emergent) or red (rescusitation). Presenting complaints, admission diagnoses, comorbidities, length of stay, and 'events' during admission (any of 20 predefined definitive treatments that necessitates in-hospital care), vital signs and routine laboratory tests taken in the ED were aslo included in the database.

RESULTS

Between September 5(th) 2013 and December 6(th) 2013, 6005 patients were included in the database and the biobank (94.1 % of all admissions). Of these, 1978 (32.9 %) were categorized as green, 2386 (39.7 %) yellow, 1616 (26.9 %) orange and 25 (0.4 %) red. Median age was 62 years (IQR 46-76), 49.8 % were male and median length of stay was 1 day (IQR 0-4). No events were found in 2658 (44.2 %) and 158 (2.6 %) were admitted to intensive or intermediate-intensive care unit and 219 (3.6 %) died within 30 days. A higher triage acuity level was associated with numerous events, including acute surgery, endovascular intervention, i.v. treatment, cardiac arrest, stroke, admission to intensive care, hospital transfer, and mortality within 30 days (p < 0.001).

CONCLUSION

The TRIAGE database has been completed and includes data and blood samples from 6005 unselected consecutive hospitalized patients. More than 40 % experienced no events and were therefore potentially unnecessary hospital admissions.

[Troponin elevation in ischemic stroke patients]

Cerebrovascular and cardiovascular diseases are major causes of death and disability worldwide. Ischemic stroke is a frequent complication in cardiac diseases and, vice versa, cardiac complications commonly cause early clinical worsening and death after stroke. In the emergency setting, cardiac biomarkers (preferably troponin, cTn) are measured frequently in patients presenting with acute ischemic stroke. The measurement of cTn is recommended by the guidelines for early management of patients with acute ischemic stroke from the American Heart Association. In case of pathologic cTn elevation, physicians are confronted with diagnostic and therapeutic uncertainties. Up-to-date recommendations on interpretation and consecutive actions remain ambiguous because cTn elevations may originate from causes other than acute coronary disease and because clinical signs and symptoms of acute coronary disease may be obscured by neurological deficits of the stroke. The application of modern, high-sensitive cTn assays that detect even minor cTn elevations has rather aggravated the dilemma of how to interpret this finding in patients with ischemic stroke.This article gives an overview on possible mechanisms of the frequently observed cTn elevation in ischemic stroke patients and offers help on interpretation and meaningful actions.

Hyponatraemia at hospital admission is a predictor of overall mortality

BACKGROUND

Hyponatraemia is a prognostic marker of increased mortality and morbidity in selected groups of hospitalised patients. The aim of the present study was to examine the prevalence and prognostic significance of hyponatraemia at hospital admission in an unselected population with a broad spectrum of medical and surgical diagnoses.

METHODS

Consecutive patients >40 years of age admitted to a general district hospital in Greater Copenhagen between 1 April 1998 and 31 March 1999. Median follow-up time was 5.16 years (range 0-4372 days). Plasma sodium measurements were available in 2960 patients, and hyponatraemia defined as P-Na(+) <137 mmol/L at hospital admission was present in 1105 (37.3 %) patients.

RESULTS

One-year mortality was higher for hyponatraemic patients than for normonatraemic patients: 27.5% versus 17.7%. Moreover, hyponatraemia was an independent predictor of short and long-term all-cause mortality after 1 year and after the entire observation period respectively: hazard ratio (HR) 1.6 (95 % confidence interval (CI) 1.4-1.9, P < 0.0001) and HR 1.4 (95 % CI 1.3-1.6, P < 0.0001). Patients with hyponatraemia had longer hospitalisations than patients with normonatraemia: 7.6 (±0.38) days vs 5.6 (±0.21) days, P < 0.001. There was no interaction between hyponatraemia at admission and any admission diagnoses (P > 0.05 for all interaction analyses).

CONCLUSION

Hyponatraemia is associated with increased all-cause mortality and longer admission length independently of diagnosis and clinical variables.

Retrospective Evaluation of Two Fast-track Strategies to Rule Out Acute Coronary Syndrome in a Real-life Chest Pain Population

BACKGROUND

The European Society of Cardiology (ESC) guideline on non-ST-elevation acute coronary syndrome (N-STE ACS) proposed a new ACS rule-out protocol.

OBJECTIVES

To evaluate this new tool, which uses diagnostic levels of high-sensitivity troponin T (hs-TnT; > 14 ng/L) in a slightly modified version and compare this to a recently proposed approach using undetectable levels of hs-TnT to rule out patients.

METHODS

There were 534 consecutive patients with suspected ACS included. Protocol 1: symptom duration, hs-TnT at 0 and 6-9 h, Global Registry of Acute Coronary Events (GRACE) score, and symptom status at 6-9 h. Protocol 2: a single blood sample of hs-TnT. The primary endpoint was a discharge diagnosis of ACS by blinded adjudication. Secondary endpoints were ACS re-admission < 30 days and 1-year mortality.

RESULTS

Protocol 1 classified 434/534 (81%) patients, with 27.9% being ruled out. All myocardial infarctions were correctly ruled in, but 15 cases of unstable angina were missed, resulting in a sensitivity and negative predictive value of 87.3% (79.6-92.5%) and 87.6% (80.4-92.9%), respectively. Protocol 2 ruled out 17.5% of the population, yielding a sensitivity and negative predictive value of 94.1% (88.2-97.6%) and 90.8% (81.9-96.2%), respectively. Both protocols correctly ruled in 2/3 patients with ACS re-admission < 30 days and 55/56 1-year fatalities.

CONCLUSION

The present study confirms the diagnostic value of a modified version of the ESC rule-out protocol (Protocol 1) in N-STE ACS patients, but also suggests that a simpler protocol using undetectable levels of hs-TnT (Protocol 2) could provide a similar or even superior sensitivity.

Pentraxin-3 level at admission is a strong predictor of short-term mortality in a community-based hospital setting

BACKGROUND

The pattern recognition molecule pentraxin-3 (PTX3) is a novel potential marker of prognosis, as elevated levels are associated with both disease severity and mortality in patients with a wide range of conditions. However, the usefulness of PTX3 as a prognostic biomarker in a general hospital setting is unknown.

PATIENTS AND METHODS

The study cohort consisted of 1326 unselected, consecutive patients (age >40 years) admitted to a community hospital in Copenhagen, Denmark. Patients were followed until death or for a median of 11.5 years after admission. The main outcome measure was all-cause mortality. Serum samples collected from patients at admission and from 192 healthy control subjects were quantified for PTX3 level by enzyme-linked immunosorbent assay.

RESULTS

PTX3 was elevated in patients (median 3.7 ng mL(-1) , range 0.5-209.8) compared with healthy nonhospitalized subjects (median 3.5 ng mL(-1) , range 0.0-8.3; P = 0.0003). Elevated PTX3 levels, defined as above the 95th percentile of the concentration in healthy subjects, were associated with increased overall mortality during the study (P < 0.0001). This increase in mortality was greatest in the short term, with an unadjusted hazard ratio (HR) of 6.4 [95% confidence interval (CI) 3.8-11.0] at 28 days after admission, compared to 1.7 (95% CI 1.4-2.0) at the end of follow-up. These results were still significant after adjustment for age, gender and glomerular filtration rate: adjusted HR of 5.0 (95% CI 2.9-8.8) and 1.4 (95% CI 1.2-1.8), respectively.

CONCLUSION

These results suggest that PTX3 could be a widely applicable marker of short-term mortality in hospitalized patients and may be useful in the initial risk stratification.

High-sensitivity cardiac troponin T in patients with intermittent claudication and its relation with cardiovascular events and all-cause mortality--the CAVASIC Study

BACKGROUND

Serum concentrations of high-sensitivity cardiac troponin T (hs-cTnT) are elevated in various diseases. The role of this marker in peripheral arterial disease (PAD) has not been fully investigated.

METHODS

Hs-cTnT was measured in the CAVASIC Study, a male cohort of 235 patients diagnosed with intermittent claudication and 249 age- and diabetes-matched controls. Patients with symptomatic PAD were prospectively followed for a median time of 7 years. The association of hs-cTnT with PAD, cardiovascular disease (CVD) at baseline as well as incident CVD and all-cause mortality during follow-up was analyzed.

RESULTS

Detectable hs-cTnT was associated with an 84% higher probability for symptomatic PAD at baseline: OR = 1.84, 95%CI 1.05-3.21, p = 0.03. Inclusion of ln-NT-proBNP or prevalent CVD abolished this association (both OR = 1.22, p = 0.52). However, detectable hs-cTnT was associated with prevalent CVD (n = 69) in PAD patients independent from ln-NT-proBNP: OR = 3.42, p = 0.001. In the adjusted Cox regression analysis detectable (HR = 2.15, p = 0.05) and especially hs-cTnT ≥ 14 ng/L (HR = 5.06, p < 0.001) were predictive for all-cause mortality (n = 39) independent from ln-NT-proBNP. Furthermore, hs-cTnT ≥ 14 ng/L was significantly associated with incident CVD (n = 66): HR = 3.15, 95%CI 1.26-7.89, p = 0.01.

CONCLUSIONS

This study in male patients with intermittent claudication and age- and diabetes-matched controls revealed hs-cTnT to be associated with PAD and prevalent CVD. The latter association was even significant after considering NT-proBNP. Prospectively, in PAD patients hs-cTnT was predictive for incident cardiovascular diseases and all-cause mortality. Thus, hs-cTnT could be a surrogate marker for cardiomyocyte damage also in symptomatic PAD patients.

High-sensitivity troponin as an outcome predictor in acute medical admissions

BACKGROUND

Troponin estimation is increasingly performed on emergency medical admissions. We report on a high-sensitivity troponin (hscTn) assay, introduced in January 2011, and its relevance to in-hospital mortality in such patients.

AIM

To evaluate the impact of hscTn results on in-hospital mortality and the value of incorporating troponin into a predictive score of in-hospital mortality.

METHODS

All patients admitted as general medical emergencies between January 2011 and October 2012 were studied. Patients admitted under other admitting services including cardiology were excluded. We examined outcomes using generalised estimating equations, an extension of generalised linear models that permitted adjustment for correlated observations (readmissions). Margins statistics used adjusted predictions to test for interactions of key predictors while controlling for other variables using computations of the average marginal effect.

RESULTS

A total of 11 132 admission episodes were recorded. The in-hospital mortality for patients with predefined cut-offs was 1.9% when no troponin assay was requested, 5.1% when the troponin result was below the 25 ng/L 'normal' cut-off, 9.7% for a troponin result ≥25 and <50 ng/L, 14.5% for a troponin result ≥50 and <100 ng/L, 34.4% for a troponin result ≥100 and <1000 ng/L, and 58.3% for a troponin result >1000 ng/L. The OR for an in-hospital death for troponin-positive patients was 2.02 (95% CI 1.84 to 2.21); when adjusted for other mortality predictors including illness severity, the OR remained significant at 2.83 (95% CI 2.20 to 3.64). The incorporation of troponin into a multivariate logistic predictive algorithm resulted in an area under the receiver operating characteristic curve to predict an in-hospital death of 0.87 (95% CI 0.85 to 0.88).

CONCLUSIONS

An increase in troponin carries prognostic information in acutely ill medical patients; the extent of the risk conferred justifies incorporation of this information into predictive algorithms for hospital mortality.

High sensitivity troponin T in acute medicine; more questions than answers?

BACKGROUND

Troponin testing in acute medicine is routine. The introduction of a high sensitivity assay (hs Tn T) has created uncertainty regarding the clinical significance of 'abnormal' troponin T levels. The previous assay could not detect troponin levels <30 ng/l.

AIMS AND METHODS

To characterize those with a hs Tn T ≥14 ng/l. Prospective cohort study of consecutive admissions to an acute medical unit.

RESULTS

Troponin was measured in 564 consecutive patients (∼50% of all admissions) over 1 month; was ≥14 ng/l in 224 (40%) of which 220 patients had demographic data for this analysis. Median (inter-quartile range) peak troponin was 47.5 ng/l (24-130) and 36% had a Tn T between 14 and 30 ng/l. Mean [standard deviation (SD)] age was 72 (12) years and 57% were male. Only 44 patients (20%) had an acute myocardial infarction, reflecting the increased sensitivity but reduced specificity of the assay. Prognosis was poor with 31% mortality at 1 year. Over a mean (SD) follow-up of 648 (61) days, there were 87 deaths (40%). Those with a primary non-cardiac diagnosis (n = 126) had poorer survival than those with a primary cardiac diagnosis (n = 94). Troponin elevation related to sepsis conferred a very poor prognosis with 24 deaths (70%) over the follow-up period.

CONCLUSION

Elevated hs Tn T is very common in acute medicine, but myocardial infarction as an explanation is uncommon. Overall, the prognosis is poor with a tendency to worse outcomes in those with a primary 'non-cardiac' diagnosis.