Clinical implications of circulating follistatin-like protein-1 in hemodialysis patients

Follistatin-like protein-1 (FSTL-1) is secreted glycoprotein, which regulates cardiovascular, immune and skeletal system. However, the clinical significance of circulating FSTL-1 levels remains unclear in hemodialysis patients. A total 376 hemodialysis patients were prospectively enrolled from June 2016 to March 2020. Plasma FSTL-1 level, inflammatory biomarkers, physical performance, and echocardiographic findings at baseline were examined. The primary endpoint was defined as a composite of incident CV events and death. Plasma FSTL-1 levels were positively correlated with TNF-α and MCP-1. Handgrip strength showed weak positive correlation in male patients only. In multivariate linear regression analysis, FSTL-1 level was negatively associated with left ventricular ejection fraction (β = −0.36; p = 0.011). Both cumulative event rate of the composite of CV event and death, and cumulative event rate of CV events were significantly greater in FSTL-1 tertile 3. In Cox regression analysis, FSTL-1 tertile 3 was associated with a 1.80-fold risk for the composite of CV events and death(95% confidence interval (CI), 1.06–3.08), and a 2.29-fold risk for CV events (95% CI, 1.15–4.54) after adjustment for multiple variables. In conclusion, high circulating FSTL-1 levels independently predict the composite of CV events and death, and FSTL-1 level was independently associated with left ventricular systolic dysfunction.