Comparison of Inflammatory Biomarkers in Outpatients With Prior Myocardial Infarction

Inflammatory biomarkers have been proposed for use in the risk stratification of patients with acute myocardial infarction (AMI). We examined the value of inflammatory biomarkers over clinical features for predicting cardiovascular (CV) events in stable outpatients with MI. We enrolled 430 post-MI patients and measured their levels of high-sensitivity C reactive protein (hs-CRP), growth differentiation factor-15 (GDF-15), and the interleukin-1 receptor family member called ST2 (ST2), one month after AMI. Patients were prospectively followed for 3 years. In our study cohort (mean age, 66 ± 12 years; left ventricular ejection fraction, 55 ± 13%), CV events were observed in 39 patients (9.1%). Kaplan- Meier analysis revealed that patients with high levels of GDF-15 (≥ 1221.0 ng/L) showed poorer prognoses than those with low levels of GDF-15 (< 1221.0 ng/L) (20.4% versus 3.6%, P < 0.001); hs-CRP and ST2 did not show a similar correlation with prognoses. GDF-15 remained associated with CV events after adjusting for age, chronic kidney disease, and B-type natriuretic peptide (hazard ratio, 1.001; 95% confidence interval, 1.000 - 1.001; P = 0.046). GDF-15 provided an incremental predictive value for CV events over clinical features (incremental value in global χ(2) = 43.81, P < 0.001). In outpatients with prior MI, GDF-15 was an independent indicator of CV events, unlike hs-CRP and ST2. GDF15 provided an incremental prognostic value over clinical features.