Cardiac troponin I measured with a very high sensitivity assay predicts subclinical carotid atherosclerosis: The Akershus Cardiac Examination 1950 Study.

AIMS Concentrations of cardiac troponin I (cTnI) are associated with incident ischemic stroke and predict the presence and severity of coronary atherosclerosis. Accordingly, we hypothesized that concentrations of cTnI measured with a very high sensitivity (hs-) assay would be associated with subclinical stages of carotid atherosclerosis in the general population. METHODS We measured hs-cTnI on the Singulex Clarity System in 1745 women and 1666 men participating in the prospective observational Akershus Cardiac Examination 1950 Study. All study participants were free from known coronary heart disease and underwent extensive cardiovascular phenotyping at baseline, including carotid ultrasound. We quantified carotid atherosclerosis by the carotid plaque score, carotid intima-media thickness (cIMT) and the presence of hypoechoic plaques. RESULTS Concentrations of hs-cTnI were measurable in 99.8% of study participants and were significantly associated with increased carotid plaque score (odds ratio for quartile 4 of hs-cTnI 1.60, 95% CI 1.23 to 2.09, p for trend < 0.001) and cIMT (odds ratio for quartile 4 of hs-cTnI 1.55, 95% CI 1.01 to 2.38, p for trend = 0.038), but not with the presence of hypoechoic plaques. hs-cTnI concentrations significantly improved reclassification and discrimination models in predicting carotid plaques when added to cardiovascular risk factors, no improvements were evident in predicting cIMT or hypoechoic plaques. CONCLUSION Concentrations of cTnI measured with a very high sensitivity assay are predictive of carotid atherosclerotic burden, a phenomenon likely attributable to common risk factors of subclinical myocardial injury, coronary and carotid atherosclerosis.