Evaluating of prognostic value of biomarker and upper reference limit calculating

2020 ◽  
Vol 20 (2) ◽  
pp. 79-86
Author(s):  
Nikolay S. Bunenkov ◽  
Gulnara F. Bunenkova ◽  
Vladimir V. Komok ◽  
Oleg A. Grinenko ◽  
Alexander S. Nemkov
Keyword(s):  
Logistic Regression ◽  
Data Analysis ◽  
Prognostic Value ◽  
Troponin I ◽  
Clinical Laboratory ◽  
Artery Bypass ◽  
Youden Index ◽  
Reference Limit ◽  
Saint Petersburg ◽  
Upper Reference Limit

Objective: to develop algorithm of assessment of prognostic value of biomarker (troponin I) for predicting death after coronary artery bypass grafting. Materials and methods. Data collection was performed according to prospective non-randomized clinical trial AMIRI CABG in Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia between 20162019 years with 336 patients. There is database with clinical, laboratory and instrumental data. Statistics were calculated with SAS Enterprise Guide 6.1 software. Prognostic capability of biomarker for death were evaluated with logistic regression. Spline of relation between death and biomarker level were plotted using coefficient of logistic regression and intercept. Upper reference limit was calculated with Youden index. Results. There was developed algorithm to assess prognostic value of biomarker and its usefulness for clinical application and to define upper reference limit of biomarker. This algorithm could be useful for physicians and researchers for data analysis. Conclusion. Presented algorithm of data analysis allows to assess prognostic value of novel biomarker and its clinical usefulness.

Abstract 14870: Clinical Significance of Troponin Elevation in a Contemporary Hospitalized Population: Endotypes, Morbidity and In-hospital Mortality

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Michael Briscoe ◽  
Robert A Sykes ◽  
Thomas Krysztofiak ◽  
Kenneth Mangion ◽  
Oliver H Peck ◽  
...  
Keyword(s):  
Clinical Significance ◽  
Myocardial Injury ◽  
Troponin I ◽  
Coronary Revascularization ◽  
High Sensitivity ◽  
Hospitalized Patients ◽  
Troponin Elevation ◽  
Reference Limit ◽  
Upper Reference Limit

Introduction: Unplanned hospitalizations are commonly associated with a circulating troponin concentration >99 th percentile upper reference limit (URL). In order to better understand the clinical significance of troponin elevation, we evaluated outcomes in hospitalized patients according to cardiac endotype. Methods: We prospectively screened consecutive hospitalized patients with elevated high-sensitivity troponin-I (hs-TnI) concentrations (Abbott ARCHITECT troponin-I assay; sex-specific URL, 99 th centile: male: >34ng/L; female: >16ng/L) within a regional cardiac care network (population 650,000). A cardiology clinical team adjudicated individual patient records and assigned endotypes by consensus agreement according to the Fourth Universal Definition of Myocardial Infarction (MI). Endotypes were sub-classified into etiological category by inciting event(s). Characteristics and comorbidity were compared and outcomes recorded on virtual follow-up until June 2 nd 2020. Results: A total of 390 consecutive patients with ≥1 hs-TnI value >URL between March 1-April 15, 2020, were evaluated; 44 patients were excluded ( Duplicates: 2; Missing data: 41; Research patient: 1 ). Of 346 who qualified for inclusion, an index diagnosis of Type 1 MI (T1MI), T2MI and myocardial injury were assigned in 115 (33.2%), 79 (22.8%) and 152 (43.9%) patients, respectively. Compared with T1MI, patients with T2MI and myocardial injury had lower peak hs-TnI values (median [IQR]: 86 [250-697] vs 5020 [853-7774]ng/L; p< 0.01), lower estimated 10-year survival (40.2% vs 53.4%; p=0.002), less frequently underwent coronary revascularization (1.4% vs 45.2%; p<0.0005) and had longer inpatient stay (13.0 vs 6.1 days). Inpatient and overall mortality rates from admission to follow-up (median [range]: 71 [0-151] days) were higher among patients with T2MI and myocardial injury (19.9% vs 7.8%; p=0.004; and 26.0% vs 11.3%; Log rank (Mantel-Cox) X 2 = 1.927; p=0.003) independent of similar cardiovascular risk profiles. Conclusions: Despite lower peak circulating troponin concentrations, patients with T2MI and myocardial injury had higher inpatient mortality, lower estimated 10-year survival and longer in-hospital stay compared to those with T1MI.

Emergency department triage of patients with acute chest pain: definition of cardiac troponin I decisional value to manage patients without electrocardiographic evidence of ischemia

2004 ◽  
Vol 42 (5) ◽  
Author(s):  
Pascale Beyne ◽  
Erik Bouvier ◽  
Patrick Werner ◽  
Pierre Bourgoin ◽  
Damien Logeart ◽  
...  
Keyword(s):  
Chest Pain ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Acute Chest Pain ◽  
Final Diagnosis ◽  
Cardiac Troponin I ◽  
Reference Limit ◽  
Coronary Syndrome ◽  
Definition Of ◽  
Upper Reference Limit

AbstractThe aim of this study was to define the use of a new cardiac troponin I (cTnI) assay for emergency patients with chest pain and no specific electrocardiographic changes consistent with the presence of ischemia. Patients (n=106) admitted in Emergency/Cardiology Departments for chest pain and suspicion of acute coronary syndrome (ACS) were randomized into two diagnosis groups (ACS or non-ACS) by two independent cardiologists. cTnI measurements were performed at admission, and 6 hours and 12 hours later with a new generation assay (Access AccuTnI, Beckman Coulter). Using an upper reference limit of 0.04 μg/l, 27 patients had a cTnI elevation not related to the final diagnosis of ischemia; the positive predictive value (PPV) was 67% with specificity 48%. The decisional value was re-defined and set at 0.16 μg/l, a concentration corresponding to the 99th percentile of the non-ACS patient group. Precision (coefficient of variation) was 8% at this level, PPV 97% and specificity 98%. This new decisional value is now used in our institution and could be included in standard care guidelines to improve the management of patients presenting chest pain in emergency departments.

scholarly journals Improved detection of minor ischemic myocardial injury with measurement of serum cardiac troponin I

1997 ◽  
Vol 43 (11) ◽  
pp. 2047-2051 ◽  
Author(s):  
Fred S Apple ◽  
Alireza Falahati ◽  
Pamela R Paulsen ◽  
Elizabeth A Miller ◽  
Scott W Sharkey
Keyword(s):  
Cardiac Troponin ◽  
Myocardial Injury ◽  
Troponin I ◽  
Cardiac Troponin I ◽  
Clinical Sensitivity ◽  
Reference Limit ◽  
Normal Limits ◽  
Serial Serum ◽  
Upper Reference Limit ◽  
Serum Cardiac Troponin

Abstract This study compared the diagnostic accuracy of the measurement of serum cardiac troponin I (cTnI) with creatine kinase (CK) MB mass in patients with minor myocardial injury whose measured total CK activity did not exceed twice the upper reference limit (300 U/L for men; 200 U/L for women). Forty-eight consecutive patients presenting with chest pain and with in-hospital documentation of myocardial injury were enrolled. Electrocardiogram, echocardiogram, and serial serum CK-MB mass, cTnI, and total CK were measured over 36 h after admission. Peak total CK activity was within normal limits in 28 patients (58%). The mean (±SD) peak CK-MB mass and cTnI concentrations were: 16.4 (11.8) μg/L and 132 (13.0) μg/L; respectively. The peak biochemical marker index (defined as CK-MB or cTnI divided by its respective upper reference limit) was significantly (P &lt;0.05) higher for cTnI than for CK-MB from 7 to 36 h. The clinical sensitivity for detection of myocardial injury for cTnI was 100% [95% confidence interval (CI): 87.2% to 100%], compared with 81.8% (CI: 67.3% to 91.8%) for CK-MB. Thus, cTnI was more sensitive than CK-MB mass for detection of myocardial injury in patients with small increases of total CK.

Analytical evaluation of the new Beckman Coulter Access high sensitivity cardiac troponin I immunoassay

2017 ◽  
Vol 56 (1) ◽  
Author(s):  
Giuseppe Lippi ◽  
Anna Ferrari ◽  
Giorgio Gandini ◽  
Matteo Gelati ◽  
Claudia Lo Cascio ◽  
...  
Keyword(s):  
Cardiac Troponin ◽  
Troponin I ◽  
Limit Of Detection ◽  
High Sensitivity ◽  
Cardiac Troponin I ◽  
Analytical Performance ◽  
The Novel ◽  
Reference Limit ◽  
Automated Immunoassay ◽  
Upper Reference Limit

AbstractBackground:This study was aimed to evaluate the analytical performance of the novel chemiluminescent and fully-automated Beckman Coulter Access hsTnI high-sensitivity immunoassay for measurement of cardiac troponin I (cTnI).Methods:The study, using lithium heparin samples, included assessment of limit of blank (LOB), limit of detection (LOD), functional sensitivity, linearity, imprecision (within run, between-run and total), calculation of 99th percentile upper reference limit (URL) in 175 healthy blood donors (mean age, 36±12 years; 47% women) and comparison with two other commercial cTnI immunoassays.Results:The LOB, LOD and functional sensitivity of Access hsTnI were 0.14, 0.34 and 1.35 ng/L, respectively. The within-run, between-run and total imprecision was 2.2%–2.9%, 4.6%–5.4%, and 5.4%–6.1%, respectively. The linearity was excellent in the range of cTnI values between 0.95 and 4195 ng/L (r=1.00). The 99th percentile URL was 15.8 ng/L. Measurable cTnI values were found in 173/175 healthy subjects (98.9%). Good agreement of cTnI values was found with AccuTnI+3 (r=0.97; mean bias, −9.3%), whereas less satisfactory agreement was found with Siemens Dimension Vista cTnI (r=0.95; mean bias, −55%).Conclusions:The results of our evaluation of the Beckman Coulter Access hsTnI indicate that the analytical performance of this fully-automated immunoassay is excellent.

scholarly journals SAS Enterprise Guide 6.1 for physicians: correlation analysis

2020 ◽  
Vol 20 (1) ◽  
pp. 51-56
Author(s):  
Nikolay S. Bunenkov ◽  
Gulnara F. Bunenkova ◽  
Vladimir V. Komok ◽  
Oleg A. Grinenko ◽  
Alexander S. Nemkov
Keyword(s):  
Clinical Trial ◽  
Data Analysis ◽  
Correlation Analysis ◽  
Randomized Clinical Trial ◽  
Clinical Laboratory ◽  
Analysis Data ◽  
Saint Petersburg ◽  
Develop Algorithm ◽  
Efficient Data ◽  
Medical University

Objective: to develop algorithm of correlation analysis of prospective non-randomized clinical trial AMIRICABG (ClinicalTrials.gov Identifier: NCT03050489) data using SAS Enterprise Guide 6.1. Materials and methods. Data collection was performed according prospective non-randomized clinical trial AMIRICABG (ClinicalTrials.gov Identifier: NCT03050489) in Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia between 20162019 years with 336 patients. There is database with clinical, laboratory and instrumental data. Correlation analysis was performed with SAS Enterprise Guide 6.1. Results. There was developed algorithm of correlation analysis data of prospective non-randomized clinical trial AMIRICABG (ClinicalTrials.gov Identifier: NCT03050489). This algorithm could be useful for physicians and researchers for data analysis. Conclusion. Presented algorithm of correlation analysis could make easier and improve efficient data analysis with SAS Enterprise Guide 6.1.

scholarly journals Temporal Evolution of Serum Concentrations of High‐Sensitivity Cardiac Troponin During 1 Year After Acute Coronary Syndrome Admission

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Victor J. van den Berg ◽  
Rohit M. Oemrawsingh ◽  
Victor A. W. M. Umans ◽  
Isabella Kardys ◽  
Folkert W. Asselbergs ◽  
...  
Keyword(s):  
Acute Coronary Syndrome ◽  
Cardiac Troponin ◽  
Troponin I ◽  
Temporal Evolution ◽  
High Sensitivity ◽  
Interindividual Variation ◽  
Mixed Effect ◽  
Reference Limit ◽  
Coronary Syndrome ◽  
Upper Reference Limit

Background Detailed insights in temporal evolution of high‐sensitivity cardiac troponin following acute coronary syndrome (ACS) are currently missing. We aimed to describe and compare the post‐ACS kinetics of high‐sensitivity cardiac troponin I (hs‐cTnI) and high‐sensitivity cardiac troponin T (hs‐cTnT), and to determine their intra‐ and interindividual variation in clinically stable patients. Methods and Results We determined hs‐cTnI (Abbott) and hs‐cTnT (Roche) in 1507 repeated blood samples, derived from 191 patients with ACS (median, 8/patient) who remained free from adverse cardiac events during 1‐year follow‐up. Post‐ACS kinetics were studied by linear mixed‐effect models. Using the samples collected in the 6‐ to 12‐month post‐ACS time frame, patients were then considered to have chronic coronary syndrome. We determined (differences between) the average hs‐cTnI and average hs‐cTnT concentration, and the intra‐ and interindividual variation for both biomarkers. Compared with hs‐cTnT, hs‐cTnI peaked higher (median 3506 ng/L versus 494 ng/L; P <0.001) and was quicker below the biomarker‐specific upper reference limit (16 versus 19 days; P <0.001). In the post–6‐month samples, hs‐cTnI and hs‐cTnT showed modest correlation ( r spearman =0.60), whereas the average hs‐cTnT concentration was 5 times more likely to be above the upper reference limit than hs‐cTnI. The intraindividual variations of hs‐cTnI and hs‐cTnT were 14.0% and 18.1%, while the interindividual variations were 94.1% and 75.9%. Conclusions Hs‐cTnI peaked higher after ACS and was quicker below the upper reference limit. In the post–6‐month samples, hs‐cTnI and hs‐cTnT were clearly not interchangeable, and average hs‐cTnT concentrations were much more often above the upper reference limit than hs‐cTnI. For both markers, the within‐patient variation fell largely below beween‐patient variation. Registration URL: https://www.trialregister.nl ; unique identifiers: NTR1698 and NTR1106.

scholarly journals Prevalence and prognostic value of elevated troponins in patients hospitalised for coronavirus disease 2019: a systematic review and meta-analysis

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Bing-Cheng Zhao ◽  
Wei-Feng Liu ◽  
Shao-Hui Lei ◽  
Bo-Wei Zhou ◽  
Xiao Yang ◽  
...  
Keyword(s):  
Systematic Review ◽  
Prognostic Value ◽  
Meta Analysis ◽  
Multivariable Analysis ◽  
Significant Heterogeneity ◽  
Random Effects Models ◽  
Reference Limit ◽  
Risk Of Death ◽  
Upper Reference Limit ◽  
Meta Analyses

Abstract Background The clinical significance of cardiac troponin measurement in patients hospitalised for coronavirus disease 2019 (covid-19) is uncertain. We investigated the prevalence of elevated troponins in these patients and its prognostic value for predicting mortality. Methods Studies were identified by searching electronic databases and preprint servers. We included studies of hospitalised covid-19 patients that reported the frequency of troponin elevations above the upper reference limit and/or the association between troponins and mortality. Meta-analyses were performed using random-effects models. Results Fifty-one studies were included. Elevated troponins were found in 20.8% (95% confidence interval [CI] 16.8–25.0 %) of patients who received troponin test on hospital admission. Elevated troponins on admission were associated with a higher risk of subsequent death (risk ratio 2.68, 95% CI 2.08–3.46) after adjusting for confounders in multivariable analysis. The pooled sensitivity of elevated admission troponins for predicting death was 0.60 (95% CI 0.54–0.65), and the specificity was 0.83 (0.77–0.88). The post-test probability of death was about 42% for patients with elevated admission troponins and was about 9% for those with non-elevated troponins on admission. There was significant heterogeneity in the analyses, and many included studies were at risk of bias due to the lack of systematic troponin measurement and inadequate follow-up. Conclusion Elevated troponins were relatively common in patients hospitalised for covid-19. Troponin measurement on admission might help in risk stratification, especially in identifying patients at high risk of death when troponin levels are elevated. High-quality prospective studies are needed to validate these findings. Systematic review registration PROSPERO CRD42020176747

Discordance between results for serum troponin T and troponin I in renal disease

1995 ◽  
Vol 41 (2) ◽  
pp. 312-317 ◽  
Author(s):  
V Bhayana ◽  
T Gougoulias ◽  
S Cohoe ◽  
A R Henderson
Keyword(s):  
Renal Failure ◽  
Troponin I ◽  
Troponin T ◽  
Myocardial Damage ◽  
Light Chains ◽  
Reference Limit ◽  
Clinical Investigations ◽  
Total Creatine ◽  
Upper Reference Limit ◽  
Peak Value

Abstract Two patients were investigated for unexplained increases in troponin T. In the first patient, who had rhabdomyolysis and acute renal failure, troponin T reached a peak value of 13.50 micrograms/L (67.5-fold the upper reference limit). The second patient had chronic renal failure and the troponin T peak value was 2.85 micrograms/L (14.3-fold the upper reference limit). Clinical investigations indicated no evidence of myocardial damage. Serum or plasma specimens were analyzed for total creatine kinase (CK), CK-2 mass, CK-2 isoform ratio, myoglobin, troponin T, troponin I, and myosin light chains; all except troponin I were at above-normal concentrations. We also investigated six additional renal patients with above-normal troponin T; troponin I was slightly increased in only one of these six patients. Our findings demonstrate discordance between results for troponin T and troponin I in renal patients.

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