Prognostic Value of Elevated Cardiac Troponin I Levels in Pre-dialysis Chronic Kidney Disease Patients without Cardiac Symptoms

Abstract

Introductory Concepts: Elevation of cardiac troponin I may be a marker of increased risk of cardiovascular outcomes such as left ventricular hypertrophy, congestive heart failure, ischemic heart disease and reduced survival in asymptomatic CKD patients. Aim: To measure serum cardiac troponin I concentration in pre-dialysis chronic kidney disease (CKD) patients who do not have any acute symptoms of cardiac disease and determine its relationship with cardiovascular risk factors. Methodology: Cross-sectional study conducted from January 2014 to December 2015. Blood pressure, serum cardiac troponin I, HDL-cholesterol, total cholesterol, triglyceride, fasting plasma glucose, urine and serum albumin, urine and serum creatinine concentrations were measured in 83 diagnosed chronic kidney disease patients attending the renal clinic and 83 age- and sex-matched healthy control subjects. Body mass index (BMI), estimated glomerular filtration rate (eGFR), urinary albumin-creatinine ratio (UACR) and LDL-cholesterol were calculated.  Results: CKD patients had higher cardiac troponin I, higher blood pressure, higher serum creatinine, higher UACR, higher triglyceride, lower serum albumin, lower HDL and lower eGFR than controls. Twenty-two (26.5%) patients, but no controls, had elevated cardiac troponin I.  Patients with high cardiac troponin I levels had a higher prevalence of diabetes mellitus and obesity but similar prevalence of other cardiovascular risk factors compared to patients with normal cardiac troponin I levels. Cardiac troponin I levels increased progressively with reduced renal function and the highest elevations were observed among patients in CKD stages 4 and 5. Conclusion: Elevated cardiac troponin I was associated with higher prevalence of diabetes and obesity but reduced eGFR among pre-dialysis CKD patients. Further research is required to determine the effect of reduced GFR and uremia on the diagnostic and prognostic efficiency of cardiac troponins, particularly in end-stage renal disease patients.