[Manipulation of blood pressure self-monitoring protocol values: a randomized controlled study]

Treatment monitoring of hypertensive patients can be achieved using data from blood pressure measurements obtained in follow-up visits, from sporadic 24 hours ambulatory blood pressure monitoring (ABPM) and from patients' self-measurements. Blood pressure self-measurement values seem to be the easiest to obtain. A disadvantage is the uncertainty about the accuracy with which patients report these values. In this randomised clinical trial with 48 hypertensive outpatients we compared reported self-measurements with the stored values in the devices. One group was unaware of the storing capacity of the device. All patients measured their blood pressure twice in the morning and twice in the evening over a period of 14 days. Endpoints of our analysis were the comparison of the number of measurements performed and the missing and manipulated values between the two groups. The non-informed group measured blood-pressure more frequently than the informed group (76.1 vs. 58.8 measurements; p = 0.0005). Compared to the informed group, the number of agreements between stored and reported values was smaller in the non-informed group (95.7% vs. 87.5%; p = 0.026) whereas reporting of fictional data only occurred in the non-informed group (0 vs. 55; p = 0.002). Our data show, that use of blood-pressure devices with a memory function increases the accuracy of reported self-measured values and can lead to better treatment monitoring.