Circulating MicroRNA-423-5p Serve As A Potential Diagnostic Biomaker Of In Elderly Patients With Deep-vein Thrombosis

Objective: This study was designed to investigate the diagnostic and predictive value of Plasma microRNA-423-5p(miR-423-5p)for deep vein thrombosis(DVT)in elderly patients with lower extremity fractures.Method: Prospectively collected 84 elderly patients with lower extremity fractures(? 65 years old)who under went surgical treatment of senile orthopedics in the Third Affiliated Hospital of He bei Medical University from April to August 2017.20 healthy volunteers matched by age and gender.Informed consent was signed for all patients and volunteers participating in the trial.All elderly patients with lower extremity fractures underwent deep venous color Doppler ultrasonography before and after surgery.The patients were divided into two groups according to the results of preoperative and postoperative ultrasonography: DVT group and no-DVT group(not occurred DVT during hospitalization).On the first day of the patient's admission,6 ml of fasting venous blood was taken from the patient 1 day before surgery,1 day after surgery and 7 days after surgery.After obtaining the plasma sample,the miRNA(miR-423-5p)most sensitive to DVT was first identified by microRNA sequencing.The levels of D-dimer and miR-423-5p in plasma were then determined by enzyme-linked fluorescence assay and real-time PCR(RT-PCR).The effects of age,hypertension,diabetes,trauma,surgery and DVT on the levels of D-dimer and miR-423-5p in plasma were analyzed by SPSS software.Result: Compared with the control group(con)and no DVT group,the Plasma miR-423-5p was significantly up-regulated on the first day of hospitalization in the DVT group(P < 0.05),and the fold changes were 15.47 and 2.37,respectively.In the no-DVT group,Plasma miR-423-5p expression was transiently up-regulated on the first day of admission and 1 day after surgery,but after trauma and surgery,we found that Plasma miR-423-5p expression level Presenting a down ward trend.During the perioperative period(on day 1 of admission,1 day before surgery,1 day after surgery and 7 days after surgery),the expression of Plasma miR-423-5p in DVT group was significantly higher than that in no-DVT group,and remained at a high level.Receiver Operating Characteristic(ROC)analysis showed that the area under the curve(AUC)of Plasma miR-423-5p and D-dimer was 0.663(95% CI: 0.545-0.781)and 0.491(95% CI: 0.364-0.617),respectively.Conclusion: Age,hypertension,diabetes and other factors have little effect on the expression of Plasma miR-423-5p in elderly patients with lower extremity fractures.Both trauma and surgical strikes can increase the expression level of Plasma miR-423-5p in elderly patients with lower extremity fractures,and the expression level of Plasma miR-423-5p will decrease after trauma and surgery.Only DVT patients can maintain Plasma miR-423-5p expression levels at a high level,and there is no downward trend during hospitalization.Plasma D-dimer has a lower diagnostic ability for DVT in elderly patients with lower extremity fractures.According to the characteristic curve(ROC)analysis,the diagnostic value of Plasma miR-423-5p for DVT in elderly patients with lower extremity fracture is higher than that of Plasma D-dimer.Therefore,we can conclude that Plasma miR-423-5p can be used as a novel non-invasive biomarker for DVT in elderly patients with lower extremity fractures.