Three 'Synergistic' Problems When Taking Blood Pressure

Matías Loewy

June 07, 2023

Failing to take blood pressure measurements at the doctor's office, using incorrect techniques, and a lack of validated automated blood pressure measurement devices are three problems that converge to cloud the diagnosis and management of hypertension in the Americas. Hypertension is a silent disease that affects 180 million individuals in the region, and the Pan American Health Organization (PAHO) says it is the primary risk factor for cardiovascular diseases.

Jarbas Barbosa, MD, MPH, PhD, director of the PAHO, told Medscape Spanish Edition, "We don't have specific data for each of these scenarios, but unfortunately, all three doubtless work together to make the situation worse.

"Often, the staff members at our primary care clinics are not prepared to diagnose and treat hypertension, because there aren't national protocols to raise awareness and prepare them to provide this care to the correct standard. Also, they are often unqualified to take blood pressure readings properly," he added.

This concern is reflected in the theme the organization chose this year for World Hypertension Day, which was observed on May 17: Measure your blood pressure accurately, control it, live longer! "We shouldn't underestimate the importance of taking blood pressure," warned Silvana Luciani, chief of PAHO's Noncommunicable Diseases, Violence, and Injury Prevention Unit. But, the experts stressed, it must be done correctly.

Time No Problem

It's important to raise awareness of the value of blood pressure measurement for the general population. However, as multiple studies have shown, one barrier to detecting and controlling hypertension is that doctors and other healthcare professionals measure blood pressure less frequently in clinic than expected, or they use inappropriate techniques or obsolete or uncalibrated measurement devices.

"The importance of clinic blood pressure measurement has been recognized for many decades, but adherence to guidelines on proper, standardized blood pressure measurement remains uncommon in clinical practice," concludes a consensus document signed by 25 experts from 13 institutions in the United States, Australia, Germany, the United Kingdom, Canada, Italy, Belgium, and Greece.

The first problem lies in the low quantity of measurements. A recent study in Argentina of nearly 3000 visits to the doctor's office at nine healthcare centers showed that doctors took blood pressure readings in only once in every seven encounters. Even cardiologists, the specialists with the best performance, did so only half of the time.

"Several factors can come into play: lack of awareness, medical inertia, or lack of appropriate equipment. But it is not for lack of time. How long does it take to take blood pressure three times within a 1-minute interval, with the patient seated and their back supported, as indicated? Four minutes. That's not very much," said Judith Zilberman, MD, PhD, to Medscape. Zilberman leads the Department of Hypertension and the Women's Cardiovascular Disease Area at the Argerich Hospital in Buenos Aires, Argentina, and is the former chair of the Argentinian Society of Hypertension.

Patricio López-Jaramillo, MD, PhD, told Medscape that the greatest obstacle is the lack of awareness among physicians and other healthcare staff about the importance of taking proper blood pressure measurements. López-Jaramillo is president and scientific director of the MASIRA Research Institute of the School of Medical Science at the University of Santander in Bucaramanga, Colombia, and first author of the Manual Práctico de Diagnóstico y Manejo de la Hipertensión Arterial (Practice Guidelines for Diagnosing and Managing Hypertension), published by the Latin American Hypertension Society.

"Medical schools are also responsible for this. They go over this topic very superficially during undergraduate and, even worse, postgraduate training. The lack of time to take correct measurements, or the lack of appropriate instruments, is secondary to this lack of awareness among most healthcare staff members," added López-Jaramillo, who is one of the researchers of the PURE epidemiologic study. Since 2002, it has followed a cohort of 225,000 participants from 27 high-, mid-, and low-income countries.

Zilberman added that it would be good practice for all primary care physicians to take blood pressure readings regardless of the reason for the visit and whether patients have been diagnosed with hypertension or not. "If a woman goes to her gynecologist because she wants to get pregnant, her blood pressure should also be taken! And any other specialist should interview the patient, ascertain her history, what medications she's on, and then ask if her blood pressure has been taken recently," she recommended.

Measure Well

The second factor to consider is that a correct technique should be used to take blood pressure readings in the doctor's office or clinic so as not to produce inaccurate results that could lead to underdiagnosis, overdiagnosis, or a poor assessment of the patient's response to prescribed treatments. An observational study performed in Uruguay in 2017 showed that only 5% of 302 blood pressure measurements followed appropriate procedures.

A new fact sheet from the PAHO lists the following eight requirements for obtaining an accurate reading: don't have a conversation, support the arm at heart level, put the cuff on a bare arm, use the correct cuff size, support the feet, keep the legs uncrossed, ensure the patient has an empty bladder, and support the back.

Though most guidelines recommend taking three readings, the "pragmatic" focus proposed in the international consensus accepts at least two readings separated by a minimum of 30 seconds. The two readings should then be averaged out. There is evidence that simplified protocols can be used, at least for population screening.

The authors of the new document also recommend preparing the patient before taking the measurement. The patient should be asked not to smoke, exercise, or consume alcohol or caffeine for at least 30 minutes beforehand. He or she should rest for a period of 3 to 5 minutes without speaking or being spoken to before the measurement is taken.

Lastly, clinically validated automated measurement devices should be used, as called for by the PAHO HEARTS initiative in the Americas. "The sphygmomanometer or classic aneroid tensiometer for the auscultatory method, which is still used way too often at doctor's office visits in the region, has many weaknesses — not only the device itself but also the way it's used (human error). This produces a rounded, approximate reading," stressed Zilberman.

Automated devices also minimize interactions with the patient by reducing distractions during the preparation and measurement phases and freeing up time for the healthcare professional. "To [check for a] fever, we use the appropriate thermometer in the appropriate location. We should do the same for blood pressure," she added.

The STRIDE-BP database, which is affiliated with the European Society of Hypertension, the International Society of Hypertension, and the World Hypertension League, contains an updated list of validated devices for measuring blood pressure.

The signers of the consensus likewise recognized that, beyond taking blood pressure measurements during office visits, the best measurements are those taken at home outside the context of medical care (doctor's office or clinic) and that the same recommendations are directly applicable. "Few diseases can be detected so easily as with a simple at-home assessment performed by the individual himself or herself. If after three consecutive measurements, readings above 140/90 mm Hg are obtained, the individual should see the doctor to set up a comprehensive treatment program," said Pablo Rodríguez, MD, secretary of the Argentinian Society of Hypertension. From now through September 14 (Day for Patients With Hypertension), the society is conducting a campaign to take blood pressure measurements at different locations across the country.

Zilberman and López-Jiménez have disclosed no relevant financial relationships.

Follow Matías A. Loewy from Medscape Spanish Edition on Twitter @MLoewy.

This article was translated from the Medscape Spanish Edition.


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