[메디칼업저버 박선혜 기자] Medical staff, patients, and the public are increasingly interested in cuffless blood pressure monitoring devices (hereafter referred to as blood pressure monitors) such as smart watches, but academics are halting because they are not suitable for actual clinical use.
The European Society for Hypertension (ESH) released a statement by experts on the ‘cuffless blood pressure monitor’ with the opinion that the new cuffless blood pressure monitor is not suitable for clinical application because the accuracy of the new blood pressure monitor has not been verified. The statement was published online in the June 17th edition of the Journal of Hypertension.
At the same time, the Korean Society of Hypertension is also of the position that there is a limit to using the smart watch to manage high blood pressure patients due to the problem of blood pressure correction.
The cuffless sphygmomanometer is expected to increase the awareness of hypertension and improve blood pressure management and control. However, if a standardized accuracy evaluation method is not prepared, its widespread use is expected to be difficult.
What are the limits of the upper arm sphygmomanometer using the cuff?
The cuffed brachial sphygmomanometer used in all studies demonstrating the clinical benefit of lowering blood pressure is recommended for use in the office, home, and activity blood pressure measurement.
However, the brachial sphygmomanometer measurement method has two limitations. First, since blood pressure is measured intermittently in a static state, it is impossible to detect and record rapid and dynamic blood pressure changes in response to physical and mental activities in daily life.
In addition, errors related to the size, shape, and position of the cuff used can occur, and when the cuff is inflated, the limbs are compressed, causing anxiety and discomfort in the user during daily activities or sleeping, which can affect blood pressure measurement.
Representative examples of cuffless blood pressure monitors include wearable devices including smart watches equipped with new algorithms and sensors.
It is possible to continuously monitor blood pressure while measuring blood pressure in a comfortable state with minimal intervention from the user. In addition, detailed information on the pattern of daily fluctuations in blood pressure can be presented.
Cuff-free sphygmomanometer readings questionable
With cuffless blood pressure monitors on the market, interest from doctors, patients, and the public is high. The problem is that it is necessary to understand the accuracy and limitations of the blood pressure monitor before using the cuffless blood pressure monitor.
Blood pressure values measured with a cuffless blood pressure monitor may not be the same as those of a cuff blood pressure monitor used in clinical practice. In other words, it is not known whether the blood pressure value suggested by the cuffless sphygmomanometer is underestimated or overestimated.
For this reason, if an excessive blood pressure value is temporarily measured in daily life, it may cause anxiety in the user and may lead to clinical treatment or visit to the emergency room. If your blood pressure is underestimated, you give the wrong confidence that there is nothing wrong with your blood pressure.
The Korean Society for Hypertension is wary of the clinical use of smart watches equipped with a function to measure blood pressure without a cuff.
Blood pressure measurement using a smart watch can increase awareness of blood pressure and accelerate the time of high blood pressure screening, but the reason is that there is a limit to blood pressure correction.
According to the society, the blood pressure measurement mobile application of the Samsung Galaxy Watch calibrates the blood pressure measured three times in a row, unlike creating a standard curve when correcting blood pressure. If the user’s psychology is unstable or his health is not good at the time of measurement, it may appear high and the blood pressure correction may be performed incorrectly and the user’s blood pressure may be measured inappropriately.
As a solution to this problem, the society has proposed a method of calibrating smart devices such as Galaxy Watch at 3-month intervals in the treatment room.
Difficult to recommend before developing a standardized accuracy evaluation method for each device
In a statement, ESH stresses the need to develop an internationally accepted standardized accuracy assessment method for cuffless blood pressure monitor validation.
The clinical usefulness of such a device should be demonstrated in conjunction with and as an alternative to currently recommended blood pressure measurement methods in healthy individuals and patients with suspected or diagnosed hypertension.
Until the problem is resolved, ESH conclusions are that cuffless sphygmomanometers should not be used in the clinical diagnosis or management of hypertension.
Similarly, the Korean Society of Hypertension recommends that smartwatch blood pressure monitors should not be used to diagnose high blood pressure, heart-related or other medical conditions, as there are limited validation data on the range of hypertension and no studies on hypertensive patients.
Professor George Stergiou of the University of Athens, Greece, who led the development of the ESH statement, said, “I think cuffless sphygmomanometers have great potential and will be useful tools in the future. However, cuffless sphygmomanometers have not yet been validated. “You have to be aware that you can’t know if the results are accurate.”
In particular, the cuffless blood pressure monitor measures blood pressure by applying various technologies rather than one, and the verification process is complicated, so a specialized verification protocol for each device must be prepared.
Professor Stergiou said, “A lot of work is being done to develop a standardized accuracy evaluation method that verifies cuffless blood pressure monitors. The problem is that the technology applied to each device is different, so one standardized evaluation method cannot be applied to all devices. Therefore, we cannot recommend the use of a blood pressure monitor without a cuff in clinical practice because other standardized evaluation methods need to be prepared.”
“The cuffless sphygmomanometer is only a good idea,” he added.