[Reproducibility of short-term variability indicators of blood pressure]

The aim of this study was to estimate the degree of reproducibility of blood pressure (BP) variability profile between 2 clinic visits. We recruited 15 untreated subjects (6 hypertensives, 9 normotensives) from the outpatient clinic. This group had undergone at least one BP measurement by the same investigator (A.G.). The subjects underwent 5-min BP monitoring (Finapres) during standing and after a rest in a supine position, at 10 AM and at 23 degrees C in a quiet room. Measurements were repeated after 7 days. A fast Fourier transform algorithm was used for analysis. There was no order effect with no difference between visits 1 and 2. Coefficients of variation (CV) for systolic BP, diastolic BP and heart rate were 9, 6 and 12%. High CVs of 20% were observed for the overall variability (total power) and the low frequency (LF, Mayer wave) component of BP. However the normalized LF (LF/total area) exhibited a acceptable CV of 15%. In conclusion the BP variability profile differences observed between visits might reflect intrasubject effect. This should be considered for assessing BP variability profile and for drug trial design.