The Journey of Measuring Blood Pressure: Why Did Humanity Try to Measure Blood Pressure? From Trial and Error to Global Adoption and the Evolution of Hypertension Standards

Having a cuff wrapped around your arm during a health checkup and being told, “Your systolic is 130, diastolic is 85.” Or measuring your blood pressure every morning at home and recording it in a notebook.

For us today, blood pressure measurement is a completely routine act.

However, humanity’s ability to capture “the pressure of blood flowing through vessels” as a numerical value is only a few hundred years old. And the ability for “anyone to easily measure it at home” is a matter of just the last few decades.

Why did humanity try to measure blood pressure? What trial and error led to today’s blood pressure monitors? And why do standards for “hypertension” differ by country and era?

Let’s embark on a journey tracing the history of blood pressure measurement.

1. Why Did Humanity Try to Measure Blood Pressure? (Motivation and Background)

Since ancient times, humans have been able to feel the “pulse.” Chinese medical pulse diagnosis, ancient Greek humoral theory—all were based on the intuition that “something is moving inside blood vessels.”

However, “feeling a pulse” and “pressure being applied” are entirely different concepts.

The turning point came in 1628 with William Harvey’s publication of his theory of blood circulation¹. Once it was proven that “blood circulates in one direction,” a new question arose:

“If it is circulating, how much force is being applied?”

Harvey himself did not measure blood pressure, but his discovery placed the concept of “the force of blood flow = pressure” on the scientific table for the first time. From here, the challenge of blood pressure measurement began.

2. The Age of Trial and Error: The First Blood Pressure Measurements (18th–19th Century)

Inserting a Glass Tube into a Horse’s Neck (1733)

The first person to measure blood pressure was Stephen Hales, an English clergyman and natural philosopher.

In 1733, he reported a remarkable experiment in his book “Haemastaticks”². He directly connected a glass tube approximately 2.7 meters long to a horse’s carotid artery and observed how high the blood would rise. The blood surged approximately 2.5 meters up through the glass tube.

This was the first blood pressure measurement in human history. It was the moment when it became visible that blood was not simply flowing quietly, but was pushing against the vessel walls with strong “pressure.”

However, inserting a glass tube into an artery could not be used on humans. From here began a long process of trial and error to “measure blood pressure without harming the body.”

Improving Accuracy with Mercury (1828)

French physicist Jean Léonard Marie Poiseuille devised a method using a mercury manometer (U-tube mercury pressure gauge) instead of a glass tube³. Since mercury is approximately 13.6 times heavier than water, the height of the liquid column indicating blood pressure became dramatically more compact.

The unit “mmHg (millimeters of mercury)” still used for blood pressure today is a remnant of this era. However, this method was still invasive (requiring insertion of a tube into a blood vessel).

The Challenge of “Drawing” the Pulse (1860s)

French physiologist Étienne-Jules Marey developed the “sphygmograph” (pulse wave recording device), which recorded pulse waveforms from the skin surface rather than inserting a needle into a blood vessel⁴. It was a groundbreaking device that pressed a sensor against the wrist artery and drew the pulse waveform on paper.

Although it could not obtain an accurate “numerical value” for blood pressure, it was an important step showing the direction of “obtaining vascular information without injuring the body.”

The Idea of Compressing the Arm (1881)

Austrian physician Samuel Siegfried Karl Ritter von Basch developed a sphygmomanometer that used a rubber bladder to compress the artery and estimated systolic blood pressure from the pressure at the moment the pulse disappeared⁵.

This was a precursor to the idea of “estimating blood pressure by applying external pressure,” which directly connects to modern blood pressure monitors. However, accuracy and usability still had issues.

3. Completion of the Modern Sphygmomanometer: Riva-Rocci and Korotkoff (Late 19th–Early 20th Century)

Birth of the Cuff-Type Mercury Sphygmomanometer (1896)

After much trial and error, in 1896, Italian physician Scipione Riva-Rocci invented the cuff (manchette) type mercury sphygmomanometer, which is still used as a prototype today⁶.

Wrapping a rubber cuff around the arm, inflating it with air, and reading the pressure from the height of the mercury column—this simple and reproducible method quickly spread to medical facilities worldwide. However, at this stage, only systolic blood pressure (the upper number) could be measured.

Korotkoff Sounds: “Listening” to Blood Pressure (1905)

It was Russian military physician Nikolai Korotkoff who brought the cuff-type sphygmomanometer to its completed form.

In 1905, he discovered that when slowly deflating the cuff while listening to the arterial sounds at the inner elbow with a stethoscope, characteristic sounds (Korotkoff sounds) appeared and then eventually disappeared⁷.

• The point where sounds begin to be heard = Systolic blood pressure (upper number)
• The point where sounds disappear = Diastolic blood pressure (lower number)

This “auscultatory method” made it possible to non-invasively measure both systolic and diastolic blood pressure. Riva-Rocci’s sphygmomanometer and Korotkoff’s auscultatory method—the combination of these two inventions became the “standard blood pressure measurement method” used throughout the 20th century in medical facilities worldwide.

4. The Spread and History of Blood Pressure Measurement in Japan

The Meiji Era: Arriving with Western Medicine

Blood pressure monitors came to Japan during the Meiji period. After the Meiji Restoration of 1868, Japan actively adopted Western medicine, and Riva-Rocci type mercury sphygmomanometers began to be used in university hospitals and military medical facilities. However, blood pressure measurement during this era was limited to a small number of specialists.

Japan as “The Country of Stroke” and the Discovery of Hypertension

From the Taisho to early Showa periods, as Japanese blood pressure data accumulated, a shocking fact emerged. The leading cause of death among Japanese people was stroke, with hypertension lurking behind it⁸.

Particularly in the Tohoku region, the high-salt food culture of pickles and miso combined with hard labor resulted in many hypertension patients and extremely high stroke mortality rates.

The Postwar Turning Point: Universal Health Insurance and Public Health Campaigns

The “Universal Health Insurance System” achieved in 1961 had a major impact on Japan’s hypertension countermeasures. All citizens gained access to healthcare, and blood pressure measurement became established as a basic item in health examinations.

In the 1960s and 70s, salt reduction campaigns were deployed centered on the Tohoku region. Community-wide efforts in Akita and Nagano prefectures brought about dramatic decreases in stroke mortality and are internationally known as success stories in Japanese public health⁹.

The Home Blood Pressure Revolution: Electronic Blood Pressure Monitors from Japan

One of the greatest contributions in the history of blood pressure measurement in Japan is the development and spread of home electronic blood pressure monitors.

From the 1970s onward, Japanese companies such as Omron and Terumo developed a series of electronic blood pressure monitors based on the oscillometric method, which automatically provides digital measurements without a stethoscope¹⁰. This ushered in an era where anyone could easily measure blood pressure at home without medical expertise.

Furthermore, research by Professor Yutaka Imai of Tohoku University and others proved that “blood pressure measured at home” predicts future stroke and heart disease risk more accurately than “blood pressure measured in the doctor’s office”¹¹. This research became the basis for the Japanese Society of Hypertension to pioneer guidelines that emphasize “home blood pressure.”

Japan became a world leader in the field of home blood pressure measurement.

5. The Global Spread of Blood Pressure Measurement

The Framingham Heart Study: Foundation of Epidemiological Evidence (1948–)

It was the American Framingham Heart Study that proved the importance of hypertension at the global level¹².

This prospective cohort study, which began in 1948 with approximately 5,000 residents of Framingham, Massachusetts, was the first to clearly demonstrate epidemiologically that hypertension significantly increases the risk of myocardial infarction and stroke.

The modern common sense that “hypertension is a disease that should be treated” could not have been established without this study.

Europe and Large-Scale Clinical Trials

From the 1960s onward, large-scale clinical trials of antihypertensive drugs were conducted in Western countries. The American Veterans Administration (VA) trial (1967)¹³, the British MRC trial, and others successively demonstrated that “lowering blood pressure can prevent stroke and heart disease,” establishing the evidence base for antihypertensive treatment.

Establishment of International Guidelines

In 1999, the WHO (World Health Organization) and ISH (International Society of Hypertension) established the first comprehensive hypertension guidelines, setting the international standard of “140/90 mmHg or above as hypertension”¹⁴.

The Silent Killer in Developing Countries

On the other hand, in developing countries where access to blood pressure measurement is limited, hypertension rages as a “Silent Killer.” According to the WHO, approximately two-thirds of the world’s hypertension patients are concentrated in low- and middle-income countries, and the problem of undiagnosed and untreated cases is severe¹⁵.

6. Differences Between Japan and the World: Approaches to Hypertension

The Deep Relationship Between Salt and Hypertension

The daily salt intake of Japanese people is approximately 10 grams, which is about twice the WHO recommendation of less than 5 grams per day. Salt is deeply rooted in Japanese food culture through soy sauce, miso, pickles, and dried fish.

Meanwhile, in Western countries, excessive salt from processed foods and the restaurant industry is also a problem, but there are regional differences in the main complications of hypertension.

“The Country of Stroke” vs. “The Country of Heart Attacks”

Interestingly, in Japan, stroke (particularly cerebral hemorrhage) tends to be the more common complication of hypertension, while in Western countries, myocardial infarction is more prevalent. This difference is thought to involve a complex interplay of genetic backgrounds, food culture (salt-type vs. fat-type), and vascular characteristics.

Home Blood Pressure vs. Office Blood Pressure

What is most unique about hypertension management in Japan is the emphasis on “home blood pressure.”

Blood pressure is high at the hospital but normal at home—this is called “white coat hypertension.” Conversely, blood pressure is normal at the hospital but high at home—this is “masked hypertension.” Masked hypertension is easily overlooked and carries the danger of going untreated despite high risk.

The guidelines of the Japanese Society of Hypertension (JSH) were among the first in the world to clearly state the importance of home blood pressure and established separate diagnostic criteria based on home blood pressure (135/85 mmHg or above)¹⁶. This is an advanced initiative globally.

Health Examination Culture and Emphasis on Prevention

Japan has a legally mandated regular health examination system (Industrial Safety and Health Act), and blood pressure measurement is the most basic item. Corporate health checks, school health checks, specific health checkups—few countries in the world systematically monitor their citizens’ blood pressure so thoroughly.

7. Hypertension Diagnostic Criteria: The Ever-Changing Boundary Between “Normal” and “Abnormal”

The Old Common Sense: “Age Plus 90”

It is hard to believe today, but it was once widely believed that “normal systolic blood pressure = age + 90 mmHg.” Following this logic, 150 mmHg at age 60 and 160 mmHg at age 70 would be “normal.”

“It’s natural for blood pressure to rise with age. There’s no need to force it down”—this was long the common sense of the medical world as well.

Evidence Rewrites the Standards

However, as numerous epidemiological surveys and clinical trials, including the Framingham Study, accumulated evidence, it became clear that “the lower the blood pressure (within an appropriate range), the lower the cardiovascular risk.”

Below is a comparison of hypertension diagnostic criteria in current major guidelines.

Why Is the US Standard Lower?

In 2017, the American Heart Association (AHA) and the American College of Cardiology (ACC) lowered the hypertension threshold from 140/90 mmHg to 130/80 mmHg¹⁷. This decision effectively created tens of millions of new “hypertension patients” in the United States overnight.

The basis was the results of the SPRINT trial (Systolic Blood Pressure Intervention Trial). This trial showed that the group with systolic blood pressure lowered to below 120 mmHg (intensive treatment group) had significantly lower cardiovascular events and mortality compared to the group lowered to below 140 mmHg (standard treatment group)¹⁹.

Meanwhile, Europe and Japan maintained the conventional 140/90 mmHg as the basic standard while referencing the same evidence. The reasons include:

• Racial differences: Evidence from Western populations may not be directly applicable to Asians
• Side effect risks: Risk of hypotension, falls, and kidney function deterioration from excessive blood pressure lowering
• Healthcare system differences: Concerns about increased medical costs from lowering the threshold
• Differences in evidence interpretation: The fact that SPRINT trial measurements (unattended automated measurement) differ from routine office measurements

The boundary between “normal” and “abnormal” is determined not only by scientific evidence but also within social, cultural, and economic contexts.

Conclusion: The Story Behind the Numbers

The history of blood pressure measurement is a history of humanity’s inexhaustible intellectual curiosity.

• From Hales’ shocking experiment of inserting a glass tube into a horse’s neck
• To the establishment of non-invasive measurement methods by Riva-Rocci and Korotkoff
• To Japan’s pioneering spread of home blood pressure monitoring

Blood pressure measurement has descended from “the scientist’s laboratory” through “the doctor’s office” to “our homes.”

And the standards for “hypertension” continue to change with the accumulation of evidence.

What matters is not being swayed by numbers, but knowing how your blood pressure fluctuates and what influences it—and applying that knowledge to your daily life.

Every time the blood pressure cuff squeezes your arm, please remember that it contains 300 years of human wisdom and challenge.

Related Articles

• Journey to Understand Blood Vessels and Flow: From Ancient Pulse Diagnosis to Modern Functional Diagnostics
• Exercise and Vascular Health: The Effects and Mechanisms of Physical Activity on Vascular Function
• The Science of Diet and Vascular Improvement: What Should You Eat to Rejuvenate Your Blood Vessels?

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