Ambulatory Blood Pressure Monitoring in Kidney Transplant Patients: RETENAL Study

Abstract

Hypertension is common following renal transplantation, affecting up to 80% of transplant recipients. It is generally accepted that hypertension is associated with poor graft survival and reduced life expectancy, contributing to increased cardiovascular risk factors and mortality rates. The aim of the study was to compare the blood pressure (BP) control in kidney transplant patients through the use of ambulatory BP monitoring (ABMP) versus office BP measurements (oBP). A multicenter, cross-sectional, observational study was conducted in 30 nephrology/kidney transplant units. Eligible patients included hypertensive cadaveric kidney transplant recipients aged <70 years, with a functioning kidney for at least 1 year and with an estimated glomerular filtration ≥30 mL/min/1.73 m2 and a serum creatinine < 2.5 mg/dL. Recorded data included demographic characteristics, oBP, and ABPM and labroatory investigations. The 868 patients showed a mean recipient age of was 53.2 ± 11.6 years and mean follow-up after transplantation, 5.5 ± 2.8 years. Mean systolic and diastolic oBP were 140.2 ± 18 and 80.4 ± 10 mm Hg, respectively. Seventy-six percent of patients had oBP higher than or equal to 130/80 mm Hg. Mean 24 hour ABPM were 131.5 ± 14 and 77.4 ± 8.7 mm Hg for systolic and diastolic BP, respectively. Using the ABPM, we observed that 36.5% of subjects were controlled (mean 24-hour BP < 130/85 mm Hg). The two methods (oBP and ABPM) showed significant agreement. After ABPM, 65% of patients diagnosed as true controlled hypertension were considered to have white-coat RH. In clinical practice ABPM may help for better adjustment of drugs for adequate BP control.