Ambulatory Blood Pressure Monitoring in the Diagnosis and Management of Hypertension after Renal Transplantation

Abstract

Objective: To evaluate the behavior of blood pressure (BP) to ambulatory blood pressure monitoring (ABPM) in stable renal transplant recipients (LTx), comparing their findings with manual measurements. Method:Cross-sectional study including 44 recipients of LTx from quaternary public hospital, with stable renal function, between the 3th and 6th months after LTx. Agreement analyses between conventional measurement and ABPM were performed considering two limits of normality: limits I: ambulatory BP < 130/80 mmHg and mean total ABPM < 125/75 mmHg; limits II: ambulatory BP < 140/90 mmHg and mean total ABPM < 130/80 mmHg. Results: There was a predominance of men (54.5%) with a mean age of 44 years, taking antihypertensives (75%). The prevalence of maskedsystemic arterial hypertension (SAH) considering the limits I was 15.9% when compared to the closest measurement to the ABPM, and 31.8% when compared to the average of the three measurements prior to the ABPM. Considering the limits II, masked SAH occurred in 22.7% when compared with the closest measurement to the ABPM and in 38.6% when the average of the measurements was used. Nocturnal descent impairment occurred in 40 (90.9%) patients. Considering ABPM as the gold standard, the accuracy of manual gauging closest to monitoring was 72.7% for limits I. When considering the average of the measurements, the accuracy was 56.8% for the same limits. The accuracy according to the limits II was 68.2% and 54.6% for the closest measurement to the ABPM and for the average of the measurements, respectively. There was poor diagnostic agreement between ABPM and ambulatory measures (Kappa = 0.095 to 0.374). The linear coefficient (R) values for systolic pressures were 0.609 and 0.671 for the first measurement closest to the MAP and for the average of the measurements, respectively. These coefficients for diastolic pressures were 0.521 and 0.454, respectively. Conclusion: There was low agreement between manual measurements and ABPM, especially for diastolic BP. Most patients had an altered nocturnal descent. These data indicate the usefulness of ABPM in addressing hypertension in this population, as well as providing additional information regarding the circadian behavior of BP.