Elevated sST2 associates with cardiac involvement and declines after treatment in newly diagnosed patients with idiopathic inflammatory myopathies

Fig. 1. Serum sST2 levels in newly diagnosed and established IIM over time. A Serum levels of sST2 in patients with newly diagnosed IIM (n = 34) compared to IIM with established disease (n = 109) and healthy controls (n = 89). B Serum levels of sST2 in patients with newly diagnosed IIM (n = 34) at baseline and after 6, 12, and 24 months, as well as in comparison with healthy controls (n = 89). IIM: idiopathic inflammatory myopathies. * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001, ns = non-significant

Fig. 2. Baseline sST2 levels and inflammatory markers in IIM with and without CI versus RA. A Baseline sST2 levels in patients with newly diagnosed IIM and ongoing CI (n = 11) were significantly higher compared with those in patients with newly diagnosed IIM without ongoing CI (n = 23) and in patients with newly diagnosed RA (n = 32). B Among patients with established IIM, sST2 levels did not differ between those with (n = 14) and without (n = 95) previous clinical CI. C ESR levels did not differ among patients with newly diagnosed IIM with ongoing CI (n = 11), without ongoing CI (n = 23), and those with RA (n = 32). D CRP levels were significantly higher in patients with newly diagnosed RA (n = 32) compared with IIM patients with (n = 11)and without (n = 23) CI. CI: cardiac involvement, defined as the presence of myocarditis and/or pericarditis by cardiac magnetic resonance; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate; IIM: idiopathic inflammatory myopathies; RA: rheumatoid arthritis. * P < 0.05, *** P < 0.001, ns = non-significant

Fig. 3. Association of sST2 tertiles with cardiac and muscle involvement biomarkers in newly diagnosed IIM. A cTnI levels in patients with newly diagnosed IIM were significantly higher in the high sST2 tertile group compared with those in the low and middle tertile groups. B NT-proBNP levels in patients with newly diagnosed IIM were significantly higher in the high sST2 tertile group compared with those in the low and middle tertile groups. C CK levels did not differ among the tertile groups. Tertile 1 represents the lowest sST2 levels, tertile 2 represents intermediate levels, and tertile 3 represents the highest sST2 levels. CK: creatine kinase; cTnI: cardiac troponin I; IIM: idiopathic inflammatory myopathies; NT-proBNP: N-terminal pro–B-type natriuretic peptide. * P < 0.05, ** P < 0.01, *** P < 0.001, ns = non-significant