Morning blood pressure surge in renal transplant recipients: Its relation to graft function and arterial stiffness

Background: When the blood pressure rises before awakening in the morning, it is called as morning blood pressure pulse (MBPS). MBPS is considered to be an independent risk factor for cardiovascular disease. The aim of this study was to investigate the associations between MBPS, graft function, arterial stiffness and echocardiographic indices in renal transplant recipients. Methods: Among 600 renal transplant recipients, 122 patients who had a history of hypertension and were taking at least one anti hypertensive medication were enrolled in the study. Arterial stiffness was measured by carotid-femoral pulse wave velocity (PWv), and echocardiographic indices were assessed. 24 h ambulatory blood pressure was monitored for all patients. MBPS was calculated by subtracting morning systolic blood pressure from minimal asleep systolic blood pressure. Results: Mean morning, day time and asleep systolic blood pressure values were 171.2 +/- 23.9, 137.9 +/- 18.1, and 131.7 +/- 18.9, respectively. Nondipper hypertension status was observed in 93 patients. Mean MBPS was 35.6 +/- 19.5 mm Hg, means PWv was 6.5 +/- 2.0 m/s. Patients with MBPS >= 35 mm Hg, had significantly lower eGFR and higher proteinuria, PWv. higher left atrium volume and LVMI. In regression analysis, day time systolic blood pressure, asleep systolic blood pressure, morning blood pressure surge, nondipper status and left ventricular mass index were detected as the predictors of graft function. Conclusions: Increased morning blood pressure surge is associated with graft dysfunction, increased arterial stiffness and LVMI that contribute to cardiovascular mortality and morbidity in renal transplant recipients.