BACKGROUND: Low values of high-sensitivity cardiac troponin (hs-cTn) and coronary artery calcium (CAC) scores of zero are associated with a low risk for atherosclerotic cardiovascular disease (ASCVD).
OBJECTIVES: The purpose of this study was to evaluate baseline hs-cTnT and CAC in relation to ASCVD.
METHODS: Baseline hs-cTnT (limit of detection [LoD] 3 ng/l) and CAC measurements were analyzed across participants age 45 to 84 years without clinical cardiovascular disease from the prospective MESA (Multi-Ethnic Study of Atherosclerosis) in relationship to incident ASCVD.
RESULTS: Among 6,749 participants, 1,002 ASCVD events occurred during a median follow-up of 15 years. Participants with detectable CAC (20.1 vs. 5.0 events per 1,000 person-years; adjusted hazard ratio [HR]: 2.35; 95% confidence interval [CI]: 2.0 to 2.76; p < 0.001) and detectable hs-cTnT (15.4 vs. 5.2 per 1,000 person-years; adjusted HR: 1.47; 95% CI: 1.21 to 1.77; p < 0.001) had higher rates of ASCVD than those with undetectable results. Individuals with undetectable hs-cTnT (32%) had similar risk for ASCVD as did those with a CAC of zero (50%) (5.2 vs. 5.0 per 1,000 person-years). Together, hs-cTnT and CAC (discordance 38%) resulted in the following ASCVD event rates: hs-cTnT < LoD/CAC = 0: 2.8 per 1,000 person-years (reference), hs-cTnT ≥ LoD/CAC = 0: 6.8 per 1,000 person-years (HR: 1.59; 95% CI: 1.17 to 2.16; p = 0.003), hs-cTnT < LoD/CAC > 0: 11.1 per 1,000 person-years (HR: 2.74; 95% CI: 1.96 to 3.83; p < 0.00001), and hs-cTnT ≥ LoD/CAC > 0: 22.6 per 1,000 person-years (HR: 3.50; 95% CI: 2.60 to 4.70; p < 0.00001).
CONCLUSIONS: An undetectable hs-cTnT identifies patients with a similar, low risk for ASCVD as those with a CAC score of zero. The increased risk among those with discordant results supports their conjoined use for risk prediction.
Sandoval Y, et al. Atherosclerotic Cardiovascular Disease Risk Stratification Based on Measurements of Troponin and Coronary Artery Calcium. J Am Coll Cardiol. 2020 Jul 28;76(4):357-370. doi: 10.1016/j.jacc.2020.05.057.