Ambulatory blood pressure monitoring in renal transplant patients: modifiable parameters after active antihypertensive treatment

Abstract

Background Hypertension (HT) accounts for nearly 60% to 80% of renal transplant patients (RT). It is one of the most important risk factors for cardiovascular diseases and may cause chronic graft dysfunction. Therefore, it is important to accurately detect and treat HT. We aimed to evaluate the changes in ambulatory blood pressure monitoring (ABPM) parameters among hypertensive RT after active treatment compared with baseline values. Methods Thirty seven RT (25 men, 12 women, aged 49.4 ± 11.2 year) diagnosed with mild to moderate HT underwent 24-hour ABPM after a 4-week washout period (W 0). For the 23 RT with confirmed HT of a second 24-hour ABPM was recorded after 4 weeks of treatment with doxazosin GITS (−4 mg once daily in the morning), a new formulation of an α 1-receptor inhibitor (W 4). Nondippers were considered when mean blood pressure (BP) showed a ≤10% reduction during sleep. Statistical analyses included Saphiro-Wilks test, Student t test, and ANOVA. Results After active treatment systolic, diastolic, and mean BP (SBP, DBP, MBP) significantly decreased during diurnal and 24 hours but not the nocturnal period. No significant change was observed for heart rate nor for pulse pressure during any period. The prevalence dippers increased from 0% to 17% after treatment. After placebo administration 8 among 37 RT with HT diagnosed according to casual BP remained hypertensive at nighttime (but not at daytime) according to 24-hour ABPM. Conclusions Diurnal and 24-hour periods of ABPM showed significant changes in SBP, DBP, and MBP after active treatment with doxazosin GITS. No significant BP changes were observed in the nocturnal period or in dipper status. Further studies using ABPM must be undertaken to determine the optimal dosage and time of administration of antihypertensive drugs in RT.