VISIT-TO-VISIT 24 HOUR BLOOD PRESSURE VARIABILITY VS OFFICE BLOOD PRESSURE VARIABILITY UNDER ANTIHYPERTENSIVE DRUG TREATMENT

Abstract

Objective: In any treated hypertensive patient office blood pressure (BP) values differ between visits and this variability (V) has an adverse prognostic impact. Almost no information is available on visit-to-visit 24-hour(h) BPV and the consistency of its therapeutic control. Design and method: In 1114 differently treated hypertensive patients of the ELSA and PHYLLIS trials we calculated 24-h BPV by the coefficient of variation of the mean BP from yearly measurements during a 3-4 year treatment period. Calculation was also made of yearly variation of the percentage of patients achieving 24-h BP control (<130/80mmHg). Calculations were extended to day and night BP. Data were compared with office visit-to visit BPV and yearly office BP control (<140/90mmHg) and variations . Results: Visit-to-visit 24-h BPV was 20% to 30% less than office BP variability, similarly for systolic and diastolic BP and consistently for different demographic, clinical and treatment conditions. BPV was considerably greater for the night than for the daytime (%, p < 0.01) . Yearly 24-h BP control was considerably less frequent and variable than yearly office BP control and was considerably than daytime BP control. In the whole study and subgroups there was a linear correlation between office and 24-h but the correlation coefficients were never >0.20, indicating that office BPV does not precisely correspond to it is impossible to precisely predict 24-h BPV from office in individual patients. Conclusions: 24-h BPV across visits is noticeably more stable than across visit office BPV, although with a greater variability of night BP. The correlation between office and 24-h BPV is significant but the low correlation coefficient makes office BPV hardly predictive of the 24-h BP stability across visits.