Blood pressure measurements - But how?

In the year 2018, the ESC again asked - even more than ever - the question of the right method for measuring blood pressure. Meanwhile, there are many different electronic, automatic and semi-automatic blood pressure monitors in addition to the classic type.

In the year 2018, the ESC again asked - even more than ever - the question of the right method for measuring blood pressure.

Meanwhile, there are many different electronic, automatic and semi-automatic blood pressure monitors in addition to the classic cuff. In addition, the extent to which the measurement of blood pressure is changed in the presence or absence of a doctor remains to be considered. So what is the most reliable way for a doctor to measure blood pressure these days? 

It is well known that high blood pressure increases the risk of cardiovascular diseases (CVD). Studies have shown that the mortality risk approximately doubles per 20/10 mm Hg. On the other hand, a reduction in blood pressure also leads to a reduction in the risk of CVD. However, the blood pressure measurement that precedes every therapy seems to be a science in its own right.

The white glue effect

Traditionally, blood pressure is measured manually on the patient's upper arm using a cuff. Usually, this is done by a doctor or a nurse. During these measurements in the practice or clinic, some patients occasionally reported that the blood pressure values determined there were unusually high. Such values would never occur in our own measurements at home.

Research describes this phenomenon as the so-called white coat effect. Some patients tend to experience greater excitement and an associated increase in blood pressure as soon as they see or are treated by a doctor. In automated blood pressure measurement, which patients usually use at home, a deviation from the manually determined value can thus occur systolically by up to -15 mm Hg, diastolically by up to -8 mm Hg.

Cave: The guidelines state that in such a case, drug treatment of this type of hypertension should only be given if the patient has a high risk of CVD or already has blood pressure-dependent organ damage.

Blood pressure measurement at home offers advantages

Avoiding the white glue effect as a blood pressure driver in patients with a corresponding preload is certainly a great advantage of measuring blood pressure at home. But there are more of them. Blood pressure at home:

In addition, measurement via mobile, automated systems will in future make it possible to implement blood pressure values within the electronic patient file. In Great Britain, many GP's (general practitioners) already use automated self-measurement for diagnosis and therapy management.

However, there is a problem especially with the management of blood pressure reduction: More and more people need blood pressure lowering therapy in old age, but compliance is even worse with automated measurement at home than with practice-based blood pressure measurement.

Telemonitoring as an opportunity?

From today's perspective, the treatment of hypertension, in particular, is therefore predestined for the use of telemonitoring. The advantages are obvious:

In a recent study, patients were compared under self-monitoring, clinical monitoring (standard) and telemonitoring. In short, the blood pressure in telemonitoring patients decreased by -3.5 mm Hg, and in self-monitoring by -4.5 mm Hg. This shows that such new forms of blood pressure measurement and management can even have a positive effect on therapy compliance. In addition, self-monitoring is very cost-effective and with or without telemonitoring reduces blood pressure much more than standard care in the practice and clinic alone.

Cave: So-called wrist blood pressure monitors only work reliably if the patient holds the device at heart level during the measurement. Since this is an important source of error when determining blood pressure using a wrist blood pressure monitor, these devices are generally not recommended for monitoring.

The Bottom Line

Blood pressure measurement is still a challenge that is too often underestimated in everyday life and is also susceptible to disturbances (e.g. white coat effect). There is no gold standard for accurate blood pressure measurement. The spectrum continues to range from the classic blood pressure cuff to modern telemonitoring systems with a variety of options in between to organize blood pressure measurement.

Above all, it is important not to lose sight of the fact that, with all the pros and cons of the measurement methods, it is not a matter of presenting one method as superior to the other. Rather, it is important to find a possible practical solution that includes practice-based blood pressure measurement and determination at home - because this is the only way to combine the best of both worlds for the benefit of the patient.

Source:
Expert advice: How to measure blood pressure?, 26.08.2018, ESC 2018, Munich, Germany