The relevance of performing 24-hour ambulatory blood pressure and pulse waveanalysis in kidney transplant recipients.

Abstract

Hypertension guidelines recommend out-of-office blood pressure (BP) measurement especially 24-hour ambulatory measurement (ABPM), to diagnose and manage hypertension but this is not routinely performed in kidney transplant units. This study was to determine if 24-hour ABPM, compared with office BP in kidney transplant recipients, would be more informative regarding BP management, and if pulse wave analysis (PWA) would assist in risk stratification. This study included patients older than 18 years, with working graft kidney for >12months, and without problems affecting BP measurement and interpretation. After performing office BP measurements, a 24-hour ABPM with additional capability of calculating pulse wave velocity (PWV), augmentation index and central BP was undertaken. Patients were assessed for controlled hypertension, uncontrolled hypertension, masked hypertension, nocturnal hypertension, white coat hypertension, and dipping BP status. Data were analyzed using standard statistical tests. Of 30 patients, 15 were Black Africans and 15 were of Mixed Ancestry with a mean age of 48.9 years. 17 patients were males and 36.7% had controlled hypertension, 30% uncontrolled hypertension, 6.7% white coat hypertension, and 33.3% masked hypertension, of whom 70% had isolated nocturnal hypertension. 70% had a non-dipping, 26.7% a reverse dipping and only 3.3% had a normal dipping BP pattern. The mean difference between brachial systolic BP and central systolic BP was 10.4mmHg, whereas PWV and augmentation index were similar to healthy populations. Conclusion: In kidney transplant recipients, 24-hour ABPM was superior to office BP in defining hypertensive status that qualified for modification of therapy, but PWA did not contribute to risk assessment.