A small circulating miRNAs signature predicts mortality and adverse cardiovascular outcomes in chronic hemodialysis patients.

BACKGROUND: Chronic hemodialysis (HD) patients exhibit severe morpho-functional cardiac alterations, putting them at a high risk of death and adverse cardiovascular (CV) outcomes. Despite the fact that an unbalanced expression of various microRNAs (miRNAs) has been related to pathological cardiac remodeling and worse CV outcomes, scarce evidence exists on their role in this setting.

METHODS: We evaluated circulating levels of a selected miRNAs panel (30a-5p, 23a-3p, 451a and let7d-5p) in 74 chronic HD patients together with a thorough clinical and echocardiography assessment. Individuals were then prospectively followed (median 22 months). The primary endpoint was a composite of all-cause and CV mortality and non-fatal CV events.

RESULTS: Circulating levels of all miRNAs were lower in HD patients as compared with healthy controls and independently correlated to the severity of cardiac dysfunction. miRNA 30a-5p, 23a-3p and 451a expression was even lower in 30 subjects (40.5%) reaching the composite endpoint ( P  < .001), while no differences were reported for let7d-5p. The predictive value of these miRNAs was supported by univariate followed by multivariate Cox regression analyses [hazard ratio (HR) ranging from 0.943 to 0.995; P  = .05 to .02] while Kaplan-Meier analyses confirmed a faster progression to the endpoint in individuals displaying miRNA levels below an optimal receiver operating characteristic-derived cut-off value ( P ranging from .001 to <.0001; crude HRs 7.95 to 8.61).

CONCLUSIONS: Lower circulating levels of miRNA 30-5p, 23a-3p and 451a in HD patients may reflect cardiac abnormalities and predict a higher risk of worse clinical outcomes in the short mid-term. Future studies on larger HD populations are needed to generalize these findings.