by William S. Bradham, Aihua Bian, Annette Oeser, Tebeb Gebretsadik, Ayumi Shintani, Joseph Solus, Joel Estis, Quynh Anh Lu, John Todd, Paolo Raggi, C. Michael Stein
We examined the hypothesis that cardiac-specific troponin-I (cTn-I), a biomarker of myocardial injury, is elevated in patients with rheumatoid arthritis (RA). Background
RA patients have an increased incidence of heart failure (HF). Chronic myocardial injury in RA may be a mechanism for the development of HF. Methods
We compared cTn-I concentrations measured by high-sensitivity immunoassay in 164 patients with RA and 90 controls, excluding prior or active heart failure. We examined the relationship between cTn-I concentrations and cardiovascular risk factors, inflammation, and coronary artery calcium score (CACS), a measure of coronary atherosclerosis. Results
cTn-I concentrations were 49% higher in patients with RA (median 1.15 pg/mL [IQR 0.73–1.92] than controls (0.77 pg/mL [0.49–1.28](P<0.001). The difference remained statistically significant after adjustment for demographic characteristics (P?=?0.002), further adjustment for cardiovascular (CV) risk factors (P?=?0.004), inflammatory markers (P?=?0.008), and in a comprehensive model of CV risk factors and inflammatory markers (P?=?0.03). In patients with RA, cTn-I concentrations were positively correlated with age (rho?=?0.359), Framingham risk score (FRS) (rho?=?0.366), and systolic blood pressure (rho?=?0.248 (all P values =0.001)), but not with measures of inflammation or RA drug therapies. cTn-I was significantly correlated with CACS in RA in univariate analysis, but not after adjustment for age, race, sex and FRS (P?=?0.79). Further model adjustments for renal function and coronary artery disease confirmed the significance of the findings. Conclusion
High-sensitivity cTn-I concentrations are elevated in patients with RA without heart failure, independent of cardiovascular risk profile and inflammatory markers. Elevated troponin concentrations in RA may indicate subclinical, indolent myocardial injury.