Systemic vascular hemodynamics and transplanted kidney survival.

Area of Science:

• Nephrology
• Cardiology
• Transplantation Medicine

Background:

• High blood pressure and arterial stiffness are independent contributors to cardiovascular mortality in uremic patients.
• High blood pressure is a known risk factor for chronic allograft nephropathy, now termed interstitial fibrosis/tubular atrophy (IF/TA).

Purpose of the Study:

• To investigate whether determinants of heart afterload, specifically arterial stiffness and vascular resistance/impedance, accelerate kidney graft failure over long-term observation.
• To assess the independent impact of hemodynamic parameters on kidney transplant outcomes.

Main Methods:

• A noninvasive blood pressure waveform analysis (HDI/PulseWave/CR-2000) was used in 160 kidney transplant recipients.
• Hemodynamic parameters (blood pressure, pulse rate, vascular resistance, impedance, artery compliance) were assessed.
• Multiple linear regression and Cox regression analyses were employed to evaluate associations with graft function deterioration (ΔCreat) and graft loss due to IF/TA.

Main Results:

• Over a mean follow-up of 6.6 years, 32 patients lost their kidney grafts, 25 due to IF/TA.
• Increased systolic blood pressure (SBP) and initial serum creatinine were independently associated with a higher rate of creatinine increase (ΔCreat).
• Higher SBP and increased serum creatinine significantly elevated the risk of graft loss due to IF/TA.

Conclusions:

• Systemic arterial compliance, resistance, or impedance do not independently influence the rate of kidney graft function decline or the risk of IF/TA-related transplant loss.
• Systolic blood pressure (SBP) is identified as the key circulatory parameter independently affecting IF/TA progression.
• SBP should be a primary therapeutic target to preserve kidney graft function and prevent transplant loss.