High-sensitivity troponins in dialysis patients: variation and prognostic value

Superiority of high sensitivity cardiac troponin I over NT-proBNP and adiponectin for 7-year mortality in stable patients receiving haemodialysis

Patients on haemodialysis (HD) have high mortality risk, and prognostic values of the major cardiovascular biomarkers cardiac troponin I (cTnI), N-terminal pro-brain natriuretic peptide (NT-proBNP), and adiponectin should be ascertained over longer follow-up periods using higher-sensitivity assays, which we undertook. In 221 HD patients, levels of high-sensitivity (hs)-cTnI, NT-proBNP, and adiponectin, were measured using high-sensitivity assays, and their associations with all-cause mortality (ACM) and cardiovascular mortality (CVM) were prospectively investigated for 7 years. Higher hs-cTnI and NT-proBNP levels were significant risk factors for ACM and CVM in the Kaplan-Meier analysis. Multivariate Cox proportional hazards analyses in a model including hs-cTnI and NT-proBNP identified log hs-cTnI, but not log NT-proBNP, as an independent risk factor for ACM (HR 2.12, P < 0.02) and CVM (HR 4.48, P < 0.0005). Stepwise analyses identified a high hs-cTnI tertile as a risk factor for ACM (HR 2.31, P < 0.01) and CVM (HR 6.70, P < 0.001). The addition of hs-cTnI to a model including age, CRP, DM, and NT-proBNP significantly improved the discrimination of ACM and CVM each over 7 years. Conclusively, hs-cTnI was superior to NT-proBNP and adiponectin in predicting ACM and CVM over 7 years in HD patients, suggesting the significance of baseline hs-cTnI measurements in long-term management.

Clinical Interpretation of Serum Troponin in the Era of High-Sensitivity Testing

Cardiac troponin (Tn) plays a central role in the evaluation of patients with angina presenting with acute coronary syndrome. The advent of high-sensitivity assays has improved the analytic sensitivity and precision of serum Tn measurement, but this advancement has come at the cost of poorer specificity. The role of clinical judgment is of heightened importance because, more so than ever, the interpretation of serum Tn elevation hinges on the careful integration of findings from electrocardiographic, echocardiographic, physical exam, interview, and other imaging and laboratory data to formulate a weighted differential diagnosis. A thorough understanding of the epidemiology, mechanisms, and prognostic implications of Tn elevations in each cardiac and non-cardiac etiology allows the clinician to better distinguish between presentations of myocardial ischemia and myocardial injury-an important discernment to make, as the treatment of acute coronary syndrome is vastly different from the workup and management of myocardial injury and should be directed at the underlying cause.

Exploring the relation between Interleukin-6 and high-sensitive cardiac troponin T in asymptomatic hemodialysis patient: A cross-sectional study

BACKGROUND

High-sensitive cardiac troponin T (h-cTnT), which serves as a marker for myocardial damage, has also been linked to adverse outcomes in asymptomatic hemodialysis patients. This study aims to explore the correlation between interleukin-6 (IL-6) and h-cTnT in asymptomatic hemodialysis patients to unravel the relationship between inflammation and cardiovascular risk.

METHODS

A cross-sectional study involving 81 patients was conducted from November 2022 to March 2023 at An-Najah National University Hospital in Palestine. We gathered clinical data, including comorbidities, and obtained blood samples for measuring IL-6 and h-cTnT levels. We performed statistical analyses, including correlation tests and linear regression, to assess the associations between these variables.

RESULTS

The study revealed a notable increase in both h-cTnT and IL-6 levels, and a significant correlation between the two (rho = 0.463, P<0.001) in asymptomatic hemodialysis patients. Likewise, h-cTnT levels displayed positive correlations with age (rho = 0.519, P<0.001) and negative correlations with albumin (rho = -0.297, p = 0.007) and transferrin saturation (rho = -0.227, P = 0.042). IL-6 levels exhibited correlations with age (rho = 0.422, P<0.001), albumin (rho = -0.389, P<0.001), iron (rho = -0.382, P<0.001), and transferrin saturation (rho = -0.362, P = 0.001). Notably, higher h-cTnT levels were associated with diabetes, hypertension, a history of coronary artery disease, cerebrovascular accidents, older age, and male gender.

CONCLUSION

This study underscores the significant association between the inflammatory marker IL-6 and h-cTnT in asymptomatic hemodialysis patients, suggesting that inflammation may play an essential role in the elevation of h-cTnT levels. This association may have implications for predicting cardiovascular events and guiding interventions to reduce cardiovascular disease morbidity and mortality in hemodialysis patients.

Utility of Cardiac Troponins in Patients With Chronic Kidney Disease

Cardiovascular disease is a major cause of death worldwide especially in patients with chronic kidney disease (CKD). Troponin T and troponin I are cardiac biomarkers used not only to diagnose acute myocardial infarction (AMI) but also to prognosticate cardiovascular and all-cause mortality. The diagnosis of AMI in the CKD population is challenging because of their elevated troponins at baseline. The development of high-sensitivity cardiac troponins shortens the time needed to rule in and rule out AMI in patients with normal renal function. While the sensitivity of high-sensitivity cardiac troponins is preserved in the CKD population, the specificity of these tests is compromised. Hence, diagnosing AMI in CKD remains problematic even with the introduction of high-sensitivity assays. The prognostic significance of troponins did not differ whether it is detected with standard or high-sensitivity assays. The elevation of both troponin T and troponin I in CKD patients remains strongly correlated with adverse cardiovascular and all-cause mortality, and the prognosis becomes poorer with advanced CKD stages. Interestingly, the degree of troponin elevation appears to be predictive of the rate of renal decline via unclear mechanisms though activation of the renin-angiotensin and other hormonal/oxidative stress systems remain suspect. In this review, we present the latest evidence of the use of cardiac troponins in both the diagnosis of AMI and the prognosis of cardiovascular and all-cause mortality. We also suggest strategies to improve on the diagnostic capability of these troponins in the CKD/end-stage kidney disease population.

Pathophysiological concepts and screening of cardiovascular disease in dialysis patients

Dialysis patients experience 10-20 times higher cardiovascular mortality than the general population. The high burden of both conventional and nontraditional risk factors attributable to loss of renal function can explain higher rates of cardiovascular disease (CVD) morbidity and death among dialysis patients. As renal function declines, uremic toxins accumulate in the blood and disrupt cell function, causing cardiovascular damage. Hemodialysis patients have many cardiovascular complications, including sudden cardiac death. Peritoneal dialysis puts dialysis patients with end-stage renal disease at increased risk of CVD complications and emergency hospitalization. The current standard of care in this population is based on observational data, which has a high potential for bias due to the paucity of dedicated randomized clinical trials. Furthermore, guidelines lack specific guidelines for these patients, often inferring them from non-dialysis patient trials. A crucial step in the prevention and treatment of CVD would be to gain better knowledge of the influence of these predisposing risk factors. This review highlights the current evidence regarding the influence of advanced chronic disease on the cardiovascular system in patients undergoing renal dialysis.

Prognostic value of cardiac troponin in dialysis patients with paroxysmal supraventricular tachycardia

A rise in cardiac troponin I (cTnI) is common in supraventricular tachycardia (SVT). While troponin elevation in SVT is thought to be a predictor of future adverse events in patients with prior coronary artery disease, the prognostic significance of cTnI in end-stage kidney disease (ESKD) patients with SVT are not known. We aimed to examine the prognostic significance of cTnI in ESKD patients presenting with SVT in the emergency department. This was a retrospective, multiple-center observational study utilizing regularly collected electronic medical records. We screened electronic medical records of all dialysis patients presenting to the emergency departments in 5 hospitals over 12 years with SVT. These patients were divided into whether cTnI was tested, and were further stratified into the cTnI-positive and cTnI-negative groups. The primary outcome of the study was the 3-year risk of major adverse cardiovascular events (MACE). Sixty-two patients were qualified for inclusion. Fifty-seven patients (91.9%) were tested for cTnI, and 5 patients were not. Patients with the cTnI test were older (P = .03) and had a longer length of hospital stay (P < .001). Forty-seven patients (82.5%) had a positive result, and 10 (17.5%) had a negative result. A history of hypertension (P = .013) and decreased left ventricular ejection fraction (P = .048) were the independent predictors of cTnI elevation. After a mean follow-up period of 20.6 ± 14.7 months, there were no differences in 3-year MACE between patients with or without elevated cTnI levels in Kaplan-Meier analysis (P = .34). A history of coronary artery disease was the only independent predictor of 3-year MACE (P = .017). Through the subgroup analysis, a history of coronary artery disease (HR 2.73; CI 1.01-7.41; P = .049) remained an independent risk factor for 3-year MACE in patients with elevated cTnI levels. A large proportion (82.5%) of troponin elevation was observed in ESKD patients with SVT, but it had a poor correlation with MACE.

Prognostic values of high sensitivity cardiac troponin T and I for long-term mortality in hemodialysis patients

Previous studies using contemporary cardiac troponin (cTn) assays have shown conflicting results in predictability of mortality and major adverse cardiovascular events (MACEs) in hemodialysis patients. We aimed to evaluate the prognostic values of high-sensitivity cTnT (hs-cTnT) and hs-cTnI for long-term mortality and MACEs in asymptomatic chronic hemodialysis patients. 198 asymptomatic patients undergoing regular hemodialysis (age 62.4 ± 14.8 years) were enrolled. Pre-dialysis hs-cTnT and hs-cTnI levels were measured. The study outcomes were long-term all-cause mortality and MACEs. Median values of hs-cTnT and hs-cTnI were 61.1 ng/L (IQR 36.6–102.0) and 18.4 ng/L (IQR 9.5–36.6), respectively. During a median follow-up of 13.5 months, 30 (15.1%) patients developed MACEs, and 20 (10.1%) patients died. The patients in highest quartile of hs-cTnT level (≥ 102 ng/L) had increased risk of long-term mortality (HR 3.34; 95%CI 1.39–8.04, P = 0.005). However, hs-cTnI levels above highest quartile (≥ 36 ng/L) was not significantly associated with increased risk of all-cause mortality. Nevertheless, elevated level of hs-cTnT and hs-cTnI was associated with increased risk of MACEs. We demonstrated that higher level of hs-cTnT, but not hs-cTnI, was associated with increased risk of long-term mortality. Nevertheless, higher level of hs-cTnT and hs-cTnI both were associated with greater risk of long-term MACEs.

Do age-adjusted sex-specific cut-off values improve the agreement between high sensitivity cardiac troponins I and T? A retrospective study

BACKGROUND

Many reports noted a disagreement between High sensitivity cardiac Troponin (hs-cTn) assays on the diagnosis of Acute Coronary Syndrome (ACS).

METHODS

We conducted a retrospective study aiming to assess the agreement between hs-cTn T (Roche) and hs-cTn I (Abbott) in patients presenting with a suspected ACS to the emergency department at Hotel-Dieu hospital between September 2017 and October 2019 using overall, sex-specific, and age-adjusted sex-specific cut-off values. This was measured using Cohen's Kappa. We explored whether renal function, circadian rhythm, age and sex influenced the discordance. And we analyzed the trend of agreement between baseline and repeated measurements.

RESULTS

4856 patients who had simultaneous hs-cTn I and T values were retained for the analysis. 53.5% had a hs-cTn T above the overall 99th percentile, compared to 19.9% for hs-cTn I. The numbers were significantly reduced when applying age-adjusted sex-specific 99th percentile. A disagreement was seen in 34% of cases using overall 99th percentile. Using sex-specific cut off values did not impact this discordance; however, age-adjusted sex-specific cut-off values reduced the percentage of discrepancies to 15.8%. The decreased renal function had a negative effect on the agreement while the circadian rhythm had minimal effect. This initial discordance was carried forward into repeated measurements.

CONCLUSION

The disagreement between hs-cTn T and I assays could be imputed to the choice of cut-off values. The use of age-adjusted sex specific 99th percentile reduced majorly these discordances. Further studies are needed in order to evaluate their clinical utility in patients presenting with ACS.