Prognostic Value Of Circulating Cell-Free DNA In Patients With Shock Admitted To Emergency Intensive Care Unit

ObjectiveThe aim of our research was to explore the clinical prognosis value of plasma cell-free DNA(cf-DNA) admission to EICU(Emergency Intensive Care Unit) with the diagnosis of shock. MethodsIt was a prospective observational study of 69 consecutive patients with shock of the First Affiliate Hospital of Anhui Medical University in the EICU. The cf- DNA was measured by real-time quantitative PCR assay for the β-globin gene in blood samples drawn at study admission and 24 h later, while the value of lactate at admission and 24 h post-admission were detected and the Acute Physiology and Chronic Health Evaluation II(APACHE II) scores within 24 hours among these patients were investigated. A control group consisted of 30 patients matched in age and gender were also included in the meantime. End point of the study was 28-d mortality rate. Patients with the diagnosis of shock were divided into two groups which included 40 survivors and 29 non-survivors. Clinical data including cf-DNA, blood lactate and APACHE II scores at 0h, 24 h after admission in survivors and non-survivors respectively. ResultsThe median cell-free DNA concentrations from patients serum were statistically significantly higher in patient died of shock at admission and 24 h post-admission(median, 1.91*10^6 pg/ml; interquartile range(IQR), 7.81*10^5 to 4.60*10^7, and 3.82*10^6 pg/m L, IQR: 1.66*10^6 to 9.27*10^6,respectively) than in patients survived shock(median 2.85*10^5 pg/m L, IQR 7.20*10^4 to 9.35*10^5; and 5.74*10^4 pg/m L, IQR 1.12*10^4 to 5.97*10^5, respectively, P < 0.05). Both the median cf-DNA levels of 0h and 24 h hours were also higher in patients than in controls(9.09*10^3 pg/m L, IQR: 4.77*10^3 to 8.97*10^4). Using receiver operating curve(ROC) analysis, the best cut-off values of cf-DNA at admission and 24 h later for predicting 28-day mortality were 8.11*10^5 pg/ml(sensitivity 75%, specificity 71.9%) and 1.39*10^6 pg/ml(sensitivity 80%, specificity 87.5%), based on the calculated areas under the curve(AUCs) of 0.822(95% confidence interval(CI), 0.707 to 0.937), 0.861(95% CI, 0.759 to 0.963), respectively. In logistic regression analysis, both cf-DNA at 24 h after admission and lactate at 24 h later were independently associated with 28-day mortality(P < 0.05). ConclusionsCirculating level of cf-DNA at 24 h after admission was significantly higher in patients died of shock in EICU than patients survived and the predictive power was higher than that of the lactate value at 24 h post-admission.