Correlation Analysis On Neutrophil-lymphocyte Ratio And Mean Platelet Volume To Platelet Count Ratio With Prognosis In Patients With Acute Aortic Dissection

Background and objectiveAcute aortic dissection（AAD）is a life-threatening cardiovascular disease.In this disease,neutrophil-lymphocyte ratio（NLR）and mean platelet volume and platelet ratio（MPV/PLT）can be considered as prognostic indicators.This study is closely associated with the various cardiovascular disease outcomes in clinic.This study investigated the association between NLR and MPV/PLT and the prognosis of AAD patients within 24 hours after admission,and investigated whether NLR and MPV/PLT may contribute to the risk assessment of the prognosis of AAD patients.Materials and methodsFor patients diagnosed with acute aortic dissection（AAD）at the Department of Cardiovascular Surgery,Second Affiliated Hospital of Zhengzhou University from November 2015 to October 2017,according to the inclusion and exclusion criteria,88AAD patients were included in this study.Aortic CTA and/or magnetic resonance imaging（MRI）,combined with clinical signs and symptoms of the patient,were diagnosed and divided into a death group（n=29）and a survival group（n=59）based on the patient’s outcome at discharge.Collect patients’baseline data,laboratory indicators,surgical data,complications,follow-up and etc.The Statistical Package for the Social Sciences（SPSS）22.0 software and GraphPad Prism7.0 were used for all the statistical analyses.Data were calculated as frequencies and percentages for categorical variables and as mean+SD or median with interquartile range(25^th-75^thh percentile)for continuous variables.Comparisons between groups were made using chi-square tests or Fisher’s exact test for categorical variables,independent-samples Student t-tests for normally distributed continuous variables,and Mann-Whitney U tests when the distribution was skewed.Receiver operating characteristic（ROC）analyses were used to detect the cut-off value of NLR and MPV/PLT in prediction of in-hospital mortality in patients（Figure）.Acute aortic dissection patients were divided into high-NLR count and low-NLR count ratio or high-MPV/platelet count and low-MPV/platelet count groups based on the cut-off value.Cox regression analysis was used to examine the association between NLR or MPV/PLT and mortality.Potential prognostic factors were entered into univariate models of mortality.Significant factors in univariate analysis were then entered into a reverse stepwise multivariate model to test for independence.Differences in survival curves obtained using Kaplan-Meier analysis were compared using the log-rank test.Results1.A total of 88 patients with acute aortic dissection were included in the final analysis.In-hospital mortality rate was found to be 32.95%（29 of 88 patients）.Patients were divided into 2 groups as patients dying in the hospital（Group 1）and those discharged alive（Group 2）.The NLR and MPV/PLT was higher in the deceased compared to the surviving patients[median 12.16（6.94-18.65）vs.median 8.62（5.45-11.80）,P=0.027 and median 8.69（5.36-10.19）vs.median 5.73（4.18-6.91）,P=0.002]2.Receiver operating characteristic analysis revealed that a NLR measurement using a cut-off point of 11.82,NLR predicts mortality with a sensitivity of 55.2%and specificity of 6.3%.The area under the curve for this relationship is 0.645 and the95%CI is 0.514-0.777;P=0.027.ROC analysis revealed that a MPV/PLT using a cut-off point of 6.95,admission MPV/PLT predicts mortality with a sensitivity of65.5%and specificity of 78.0%.The area under the curve for this relationship is0.702 and the 95%CI is 0.577-0.826;P=0.002.According to the optimal cut-off point,the patients were divided into low NLR group（<11.82）and high NLR group（>11.82）,low MPV/PLT group（<6.95）and high MPV/PLT group（>6.95）.Patients with higher NLR and MPV/PLT had a significantly higher mortality rate（53.3%vs.22.4%,P=0.003 and 59.4%vs.17.9%,P=0.000）.3.In multivariate Cox regression analysis show age[OR=1.050（1.008-1.094）;P=0.019],operation time[OR=0.996（0.993-0.998）;P=0.000],NLR[OR=1.155（1.076-1.241）P=0.000],MPV/PLT[OR=1.079（1.012-1.150）;P=0.019]were found to be independent markers of in-hospital mortality in the study population;Accor ding to this analysis,patients with higher admissionNLR[HR=2.383（1.126-5.042）;P=0.023],and MPV/PLT[HR=4.263（1.899-9.567）;P=0.000]have a signif icantly higher mortality rate.4.Fifty-nine AAD patients who survived after operation and were discharged from hospital were followed up for 2 months to 2 years.During the follow-up period of（9.74±6.23）months,there were 7 patients died and the mortality was 11.86%（7/59）.The Kaplan-Meier survival curve results showed that the survival rate in the low NLR group was higher than that in the high NLR group during follow-up（93.3%vs.71.4%,P=0.027）.The survival rate in the low MPV/PLT group was higher than that in the high MPV/PLT group during follow-up.（93.5%vs.69.2%,P=0.017）.ConclusionsNeutrophil-lymphocyte ratio（NLR）and mean platelet volume and platelet ratio（MPV/PLT）were significantly associated with prognosis in patients with acute aortic dissection（AAD）.The independent risk factors to die in hospital is high NLR levels and high MPV/PLT.