Diagnostic Value Of Aldosterone And Plasma Renin Activity Ratio In Primary Aldosteronism

Objective:The our early research achievement [1]shows the area under the receiver operating characteristic(ROC)curve of the different positions of aldosterone to plasma renin activity ratio(ARR)were 0.711 and 0.842(P<0.01)in primary aldosteronism(PA),and upright ARR was 13(pg.d L-1)/(ng.m L-1 h-1),with sensitivity of 0.54,specificity of 0.81,the uprihgt ARR was5(pg.d L-1)(ng.m L.-1 / h-1),sensitivity of 0.83,specificity of 0.41,the supine ARR was 30(pg.d L-1)/(ng.m L-1 h-1),sensitivity and specificity 0.83,0.64 respectively,suggesting that the diagnostic efficiency of supine ARR was higher than that of the upright ARR.This study was based on the basis of previous research to verify and discuss the sensitivity,specificity and diagnostic accuracy of the supine ARR30 and the upright5,13(pg.d L-1)/(ng.m L-1 h-1)for the diagnostic point cut in the identification of PA and Essential hypertension(EH),and expand the sample volume,to determine the cut-off of ARR,improve the diagnostic level of PA,and to provide theoretical reference for clinical diagnosis.Methods:Clinical data of 178 patients hospitalized in the First Affiliated Hospital of Guangxi Medical University from January 2013 to December 2016 were collected in this study,in which 91 cases were surgically and pathologically confirmed PA patients,87 cases were diagnosed with EH patients over the same period.The gender,age,duration of hypertension,body mass index(BMI),systolic pressure,diastolic pressure,potassium,cortisol rhythm,catecholamine metabolites,24 hours urinary potassium,upright and supine plasma renin activity(PRA),plasma aldosterone concentration(PAC)of the patients were measured.Moreover,the supine and upright ARR were analyzed to ROC curve,and access the sensitivity,specificity,and coincidence rate of upright ARR for 5,13 and supine ARR for 30,and expand sample size to determine ARR cut point,the difference of ARR were compared between 2 kinds of pathological typers of PA.Besides,the sensitivity,specificity,and coincidence rate of associating upright ARR with the supine ARR in diagnosing PA were calculated.Results:1.There was no significant difference in age?diastolic blood pressure between the two groups(P>0.05).The duration of hypertension,the mean BMI,the level of serum potassium,PRA in PA group were significantly lower than that in EH group,while systolic blood pressure,the level of urinary potassium,PAC,ARR in PA group were significantly higher than that in EH group(P <0.01).2.The upright and supine ARR under the area the ROC curve(AUC)were0.867,0.951 respectively(P <0.01),the area under the ROC curve of the different positions ARR were compared(Z = 3.5,P <0.01),supine ARR has high value in screening PA diagnose.3.In this study,we found that under the ROC curve the optimal cut-off of upright ARR 6 vs upright ARR5,13{sensitivity: 0.72vs0.56,0.92,specificity: 0.85vs0.93,0.46,coincidence rate:78.5%vs74.5%,69.1%},the optimal cut-off of supine ARR27 vs supine ARR30{sensitivity: 0.85vs0.90,specificity:0.9vs0.79,coincidence rate :87.5% vs84.4%}.It was concluded that the diagnostic efficiency of upright ARR5 and 13 was less than that of standing ARR6,and the diagnostic value of supine ARR30 and ARR27 was equivalent.4.To expand the sample size to further confirm the diagnosis efficiency of screening point of previous study,the optimal cut-off of supine ARR32 vs ARR27,30{ sensitivity: 0.92vs0.82,0.88,specificity: 0.79vs0.89,0.81,coincidence rate:85.6%vs85.4%,84.6%},the optimal cut-off of upright ARR9 vsupright ARR5,6,13{sensitivity:0.88vs0.54,0.67,0.92,specificity :0.63vs0.86,0.78,0.5,coincidence rate: 75.3%vs69.6%,73%,71%},supine ARR30 still has high diagnostic value in big sample research.5.There was no significant difference in PAC,PRA and ARR between the adrenocortical adenoma and the adrenal cortical hyperplasia(P>0.05).6.Comparing the optimal cut-off point of the upright and supine ARR was located in the upright ARR between 9~13 and the supine ARR between27~32.Conclusion:1.Based on the three diagnostic cut-off points of the previous study,in this study,we find that the supine ARR 30 clinical diagnostic value is high,this cut point is proved to be worthy of being recommended as a screening point for PA patients in this region.2.The uptight ARR value can be used as an outpatients screening text,and the diagnostic value remains to be further studied.3.In this study,associating the upright ARR between 9~13 with the supine ARR between 27~32 to screen PA,which has high diagnostic value.It can be considered that the optimal cut-off point of combining upright and supine ARR is situated in this interval.4.In this study,the drug was discontinued at least 1 weeks before the screening of ARR.The method is simple and can be accepted by the patients easily,and conforms to the clinical practice.It is worthy of promotion clinically.