Growth differentiation factor 15: a biomarker searching for an indication

The diagnostic and prognostic value of growth differentiation factor-15 in systemic lupus erythematosus-associated pulmonary arterial hypertension

Growth-differentiation factor (GDF)-15 is a member of transforming growth factor-β-related cytokine and may respond to right ventricular overload. The objective of this article was to assess the diagnosis and prognostic value of GDF-15 in systemic lupus erythematosus-associated pulmonary arterial hypertension (SLE-PAH). Serum samples were obtained from 65 patients with SLE-PAH, 51 sex and age matched patients of SLE without PAH (SLE-non-PAH), and 32 healthy controls. Serum GDF-15 level was detected by enzyme-linked immunosorbent assay and the optimal cut-off point was determined by receiver operating characteristic curve. The primary end-point was death from any cause and the secondary end-point was target goal achievement (TGA). Cox regression analyses and Kaplan-Meier method were performed to identify the prognostic value of GDF-15. Serum GDF-15 levels were significantly higher in SLE-PAH patients (1112.14 ± 781.80 pg/mL) than SLE-non-PAH patients (810 ± 408 pg/mL) and healthy controls (442 ± 139 pg/mL) at baseline. The optimal cut-off value of GDF-15 in the diagnosis of SLE-PAH was 733 pg/mL (AUC = 0.84). In patients with SLE-PAH, GDF-15 level was associated with 6 min walking distance (ρ = -0.385, p = 0.017) and higher serum N terminal-pro brain natriuretic peptide (NT-proBNP) (ρ = 0.605, p < 0.001). Patients with GDF-15 > 733 pg/mL were more likely to death (adjusted hazard ratio [HR] = 4.01, 95% confidence intervals [CI]: 1.23-6.27, p = 0.041) and less likely to achieve treatment goal (adjusted HR = 0.57, 95% CI: 0.23-0.79, p = 0.028). In addition, patients with simultaneous elevation of GDF-15 and NT-proBNP showed lower proportion of TGA (p = 0.046). In conclusion, GDF-15 is a new and promising biomarker of development and prognosis in SLE-PAH. The combination of GDF-15 and NT-proBNP may provide more accurate prognostic information.