The Study Of Hydration Status In Peritoneal Dialysis Patients

ObjectiveTo investigate the role of clinical indicators in volume assessments of peritoneal dialysis patients(PD)and the association between hydration and nutrition status.We also conducted a prospective,randomized,and controlled study to investigate whether objective measurement of fluid overload with bioimpedance spectroscopy is helpful in optimizing hydration status in PD patients.Methods1.Eligible PD patients in Renji Hospital,Shanghai Jiao Tong University School of Medicine from November 2016 to November 2017 were enrolled.Demographic data of patients were collected and clinical parameters were measured.Hydration status index overhydration(OH)was measured by bioimpedance spectroscopy(BCM),and the association between clinical indicators and OH was analyzed.2.Nutrition status was assessed by serum albumin,prealbumin,normalized protein catabolic rate(nPCR)and subjective global assessment(SGA).The association between overhydration and nutrition index was analyzed.3.Eligible PD patients from November 2016 to February 2017 were enrolled,and were randomly assigned into the following 2 groups: BCM group and clinical group.Hydration status index overhydration(OH)was measured by bioimpedance spectroscopy.In patients in the BCM group,treatment was adjusted according to overhydration information measured by BCM and clinical indicators.In patients in the clinical group,treatment was based on clinical indicators alone.All patients were followed up for 48 weeks,and OH and pulse wave velocity(PWV)were compared.Result1.A total of 200 PD patients aged 56.3 ± 13.8 years with median PD duration 46.61(21.32,84.39)months were enrolled.Among them,117(58.5%)patients were males,42(21%)were diabetic and 27(13.5%)had cardiovascular disease(CVD).141(70.5%)patients were overhydrated(OH>1.1L).Compared to those with normal hydration status,the overhydrated patients had higher blood pressure,more obvious edema and higher brain natriuretic peptide(BNP)level(P all<0.05).In overhydrated patients,51(36.2%)patients had normal blood pressure,67(47.5%)patients had no edema and 46(32.6%)patients had BNP < 100pg/ml.While in normal hydrated patients,20(33.9%)patients had high blood pressure,8(13.6%)patients had edema and 46(32.6%)patients had BNP>400pg/ml.2.OH was significantly correlated with serum albumin(R=-0.370,P<0.001),prealbumin(R=-0.219,P=0.002)and nPCR(R=-0.319,P<0.001)negatively.Multivariate linear regression showed that OH was the independent associated factor of serum albumin(?=-0.674,P<0.001),prealbumin(?=-11.368,P=0.001)and nPCR(?=-0.027,P=0.002).Multivariate logistic regression showed that OH(OR=1.335,95%CI 1.033~1.727,P=0.027)was the independent associated factor of SGA.3.A total of 100 PD patients aged 55.9±13.6 years with median PD duration 56(30,82)months were enrolled,and 60 patients(60%)were males.84 patients(40 in the BCM group and 44 in the clinical group)completed 48 weeks follow-up and were analyzed.There were no change in OH in both of the groups[BCM group: 2.4(0.9,3.8)to 1.7(0.7,3.6)L,P>0.05;clinical group: 1.6(0.6,2.7)to 1.8(0.4,2.7)L,P>0.05] after 48 weeks.In patients in the BCM group,the pulse wave velocity(9.82±2.31 to 10.11±2.45m/s,P>0.05)and pulse pressure(52.08±15.10 to 52.28±18.58 mmHg,P>0.05)were stable after 48 weeks.While in patients in the clinical group there was a significant increase in pulse wave velocity(8.68±2.78 to 10.12±3.08m/s,P=0.018)and pulse pressure(49.82±14.70 to 55.59±15.30 mmHg,P=0.003)were noticed.Conclusions1.Blood pressure,edema and BNP is closely associated with hydration status in PD patients,but these clinical indicators cannot accurately reflect the hydration status in all patients.Combination of different indicators might be useful in evaluation of hydration status in PD patients.2.There is a strong association between hydration and nutrition status in PD patients.3.The application of bioimpedance spectroscopy to assess and guide hydration control may benefit for delaying the progress of arterial stiffness in PD patients,however,further studies with larger sample size and longer follow-up are needed to confirm out result.