Abstract 19814: Patients with Rheumatoid Arthritis Have Elevated High-Sensitivity Cardiac Troponin-I Concentrations Independent of Cardiovascular Risk Factors and Inflammation
Background: Patients with rheumatoid arthritis (RA) have increased cardiovascular mortality and RA is an independent risk factor for heart failure (HF). Myocardial mass is reduced in RA and indolent myocyte loss may be an underlying mechanism for the development of HF. We hypothesized that high-sensitivity, cardiac-specific troponin-I (cTn-I) concentrations, a well-established indicator of myocardial injury, may be detectable before the development of clinical HF in RA.
Methods: We measured cTn-I concentrations, in blinded fashion, using a high-sensitivity immunoassay (Singulex), inflammatory markers and cardiovascular risk factors in 164 patients with RA and 90 controls without heart failure. cTn-I concentrations were compared in RA patients and controls with adjustment for: i) age, race and gender; ii) demographics plus cardiovascular risk factors; iii) demographics plus inflammation markers; iv) a full model that included all these variables and NTproBNP. In RA patients, we examined the relationship between coronary artery calcium score (CACS) measured by EBCT and cTn-I concentrations with adjustment for clinical characteristics.
Results: Median cTn-I concentrations were 49% higher in patients with RA (1.15 pg/mL [IQR 0.73-1.92] than controls (0.77 pg/mL [0.49-1.28](P<0.001). cTn-I concentrations remained statistically significantly higher in patients with RA than controls after adjustment for demographic characteristics (P=0.002), and additional adjustment for cardiovascular risk factors (P=0.004), inflammation (P=0.008), and the full model (P=0.03). In patients with RA, cTn-I concentrations were positively correlated with age, Framingham risk score (FRS), systolic blood pressure and CACS (all P values ≤0.001), but not with measures of inflammation or RA drug therapies. The relationship between cTn-I and CACS in RA was not statistically significant after adjustment for age, race, gender and FRS (P=0.79).
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.
- © 2010 by American Heart Association, Inc.