High sensitivity-troponin I levels tied to CV risk

Elevated troponin I measured by a high-sensitivity assay correlated to risk for various CV outcomes and all-cause mortality, independent of traditional risk factors, according to findings published in Circulation.

The researchers also found that elevated troponin I was only moderately correlated with elevated troponin T, but both predicted CV risk, so they may serve as complements to each other.

Xiaoming Jia, MD, and colleagues sought to determine whether plasma troponin I measured by a high-sensitivity assay (hs-TnI; Architect Stat Troponin-I, Abbott) is associated with incident CVD and mortality in a community-based sample without prior CVD.

More sensitive assays

“Lowering the detection threshold of troponin assays has expanded the potential use of cardiac troponins from a diagnostic tool in the setting of acute coronary syndrome to a biomarker for risk stratification in individuals without known CVD,” Jia, a cardiovascular resident at Baylor College of Medicine, and colleagues wrote. “Detectable levels of cardiac troponins have been associated with increased incidence of CHD, HF and cardiovascular mortality in community-based studies.”

The researchers analyzed data from the ARIC study of participants without baseline CVD (n = 8,121; median age, 61-64 years) with a median follow-up period of approximately 15 years.

Cox proportional hazard models were used in determining associations between hs-TnI and incident CHD, ischemic stroke, atherosclerotic CVD, HF hospitalization, global CVD (defined as ASCVD and HF) and all-cause mortality, Jia and colleagues wrote. Risk prediction models were created to assess prediction improvement when hs-TnI was added to traditional risk factors used in the Pooled Cohort Equation.

In 85% of the study population, detectable hs-TnI levels were found, the researchers wrote.

Elevated hs-TnI, the highest quintile with hs-TnI at 3.8 ng/L or higher, was compared with low hs-TnI, the lowest quintile with hs-TnI at 1.3 ng/L or lower, in adjusted models.

Troponin and CV risk

Elevated hs-TnI was associated with greater incident CHD (HR = 2.2; 95% CI, 1.64-2.95) and ischemic stroke (HR = 2.99; 95% CI, 2.01-4.46) compared with low hs-TnI, Jia and colleagues. ASCVD (HR = 2.36; 95% CI, 1.86-3) and HF hospitalization (HR = 4.2; 95% CI 3.28-5.37) were also associated with elevated hs-TnI in comparison with low hs-TnI.

Jia and colleagues also noted elevated hs-TnI was associated with risk for global CVD (HR = 3.01; 95% CI, 2.5-3.63) and all-cause mortality (HR = 1.83; 95% CI, 1.56-2.14) compared with low hs-TnI.

Hs-TnI was more strongly associated with incident global CVD events in white adults compared with black adults and with incident CHD in women compared with men, according to the researchers.

High-sensitivity troponin T and hs-TnI were moderately correlated (r = 0.47) and were complementary in prediction of incident CVD events, with elevation of both troponins conferring the highest risk in comparison with elevation in either one alone, Jia and colleagues wrote.

When adding hs-TnI to the Pooled Cohort Equation model, risk prediction for ASCVD, HF and global CVD improved, the researchers wrote.

Future studies are needed to examine hs-TnI in other populations to determine potential race and sex differences in different age groups in order to create an algorithm to assess global CVD risk, Jia and colleagues wrote. – by Earl Holland Jr.

Disclosures: Jia reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.