Accuracy of sequential versus simultaneous BP measurement in assessing between-arm BP differences using the Microlife Watch BP Office

Inter-arm blood pressure (BP) differences have been established since the early
'20's of last century. Large inter-arm BP differences have been associated with
peripheral vascular diseases and reduced 10-year survival. Therefore, the
European Society on Hypertension, as well as the European Society of Cardiology
recommend in their guidelines to measure BP at both arms at a patients first
visit. The higher value should then be taken as a reference. Interestingly,
despite these clear recommendations, the guidelines do not tell how the
inter-arm BP difference should be assessed. Previous studies have shown that
simultaneous measurements are favored over sequential measurements, as the
number of patients with a large inter arm BP differences is smaller in the same
population. However, these data are based on studies in which simultaneous
measurements are - at best - taken by two similar BP devices. Recently a new BP
measurement device was introduced, with the possibility to simultaneously
measure the BP at both arms using two cuffs (Watch BP Office). This device also
allows for sequential BP measurements at both arms individually. Therefore, we
used this device to compare sequential with simultaneous interarm BP
differences.

- To elucidate whether simultaneous measurement of brachial BP may improve the
accuracy of assessment of interarm BP differences compared with sequential
interarm BP assessment

Prospective open-label crossover study including 300 persons distributed over
four different risk profile group. The risk groups are strafied according to
their age and blood presssure (see study population)

Inter-arm differences relate to and peripheral vascular diseases and all cause
mortality. Assessment of inter-arm BP differences may serve as a cheap,
non-invasive tool to assess cardiovascular risk. Sequential measurement of
inter-arm BP difference is hampered by order effects. The simultaneous
assessment of inter-arm BP difference) might overcome these problems, possibly
increasing the predictive value of inter-arm BP measurements as a marker for
atherosclerosis.

The benefit following participation includes recording of cardiovascular risk
factors and a standardized BP reading. These will be communicated to the
patient and to their doctor*s. The study burden consists of a brief
questionnaire to assess cardiovascular risk and a series of 6 consecutive BP
measurements. These measurements are not invasive and do not harm the patients.