Background: The prevalence and determinants of cardiac troponin T (cTnT) elevation in the general population are unknown, and the significance of minimally increased cTnT remains controversial. Our objective was to determine the prevalence and determinants of cTnT elevation in a large, representative sample of the general population.
Methods and results: cTnT was measured from stored plasma samples in 3557 subjects of the Dallas Heart Study, a population-based sample. cTnT elevation (> or =0.01 microg/L) was correlated with clinical variables and cardiac MRI findings. The sample weight-adjusted prevalence of cTnT elevation in the general population was 0.7%. In univariable analyses, cTnT elevation was associated with older age, black race, male sex, coronary artery calcium by electron beam CT, a composite marker of congestive heart failure (CHF), left ventricular hypertrophy (LVH), diabetes mellitus (DM), and chronic kidney disease (CKD) (P<0.001 for each). Subjects with minimally increased (0.01 to 0.029 microg/L) and increased (> or =0.03 microg/L) cTnT had a similar prevalence of these characteristics. In multivariable logistic regression analysis, LVH, CHF, DM, and CKD were independently associated with cTnT elevation.
Conclusions: In the general population, cTnT elevation is rare in subjects without CHF, LVH, CKD, or DM, suggesting that the upper limit of normal for the immunoassay should be <0.01 microg/L. Even minimally increased cTnT may represent subclinical cardiac injury and have important clinical implications, a hypothesis that should be tested in longitudinal outcome studies.