Troponin I levels in systemic sclerosis patients with myocardial involvement

Troponin I has been suggested as a more specific diagnostic biomarker for myocardial involvement in systemic sclerosis than the frequently used troponin T. The aim of this study is to evaluate the additive value of troponin I to detect myocardial involvement in systemic sclerosis. To this end, we evaluated the association between troponin I levels and myocardial involvement in systemic sclerosis patients. A cross-sectional observational study was performed, including 20 healthy controls and four groups of each 20 systemic sclerosis patients from the Leiden Combined Care in Systemic Sclerosis cohort: (1) patients with myocardial involvement, (2) patients with myositis, (3) patients with elevated troponin T and creatine kinase levels but without organ involvement, and (4) patients without any signs of organ involvement. Troponin I levels were measured using enzyme-linked immunosorbent assay. Troponin I levels were compared between the different groups using the Mann–Whitney U and Kruskal–Wallis tests. The mean age of the 80 included patients was 56 years; 61% of the study population was female. Troponin I levels were not significantly different between patients with and without myocardial involvement (2.7 (0.5–15.3) vs 1.2 (0.1–6.6) ng/L; p = 0.117). Systemic sclerosis patients were more often positive for troponin I than healthy controls (70.0% vs 30.0%; p = 0.001). Elevated troponin I was not of additional value to diagnose myocardial involvement in systemic sclerosis patients.