Background and Aims: Arterial stiffness, altered body composition (increased body fat mass and decreased soft lean mass) and cell membrane integrity (Phase Angle) are acknowledged risk factors for adverse outcomes after kidney  transplantation related to cardiovascular diseases. Phase angle is a linear method of measuring the relationship between electric resistance and reactance. Taking the arc tangent value of the ratio of reactance versus electric resistance provides us with the phase angle value. Lower phase angles appear to be consistent with low reactance and equals either cell death or a breakdown in the selective permeability of the cell membrane. The aim of the study was the assessment of the relationship between arterial stiffness and NT pro-and fat tissue parameters, cell membrane integrity marker in renal transplants recipients (RTRs).
Method: 260 stable RTRs with the mean age 52.6 years, (64.2% M) transplanted between 1994 and 2018 were randomly enrolled to the study. The following parameters of arterial stiffness were measured: brachial-ankle and carotid-femoral pulse wave velocities (baPWV left and right, cfPWV).  Moreover, body mass index (BMI), waist to hip ratio (WHR), waist circumference, body fat mass (BFM) and visceral fat area (VFA)) parameters and cell membrane integrity phase angle (PhA) were assessed with InBody 170. Additionally, NT-pro-BNP was assessed in the serum of RTRs.
Results: The median time of dialysis and after kidney transplantation was 44 and 68 months respectively. The demographic data, comorbidities, immunosuppressive regimen, the value of NT-pro BNP, PWV, fat tissue parameters and PhA were showed in table 1.

We found significant correlations between NT-proBNP, VFA, PhA, and  baPWV right (r=0.39, r=0.19, r=-0.39), baPWV left (r=0.31, r=0.21. r=-0.36) and cfPWV (r=0.35, r=0.19, r=-0.42), respectively. PhA correlated with NT-pro-BNP (r=-0.62, p=0.001).  Multivariate analysis showed significant correlation between PhA and baPWV right (β=-0.4), baPWV left (β=-0.34) and cfPWV (β=-0.41).
Conclusion:
1. NT-pro BNP, visceral fat tissue, cell membrane integrity marker influence on arterial stiffness.
2. The analysis of NT-pro BNP, visceral fat area and cell membrane integrity parameters can be used as an additional cardiovascular risk factor in RTRs.
3.  The cell membrane integrity impairment correlated with arterial stiffness and heart function (NT-pro BNP).