Hypertension: History, Epidemiology, and U.S. Public Health Impact

Introduction

Thomas Fuller, an English churchman and historian, said: "Health is not valued till sickness comes." Hypertension is one of the most life-threatening diseases in the U.S., present in almost one out of four adults. Almost half of all U.S. deaths in 2017 were primarily attributed to hypertension (Centers for Disease Control and Prevention, 2020a). This paper analyzes the historical development of this issue, evaluates the roles of public health organizations in addressing it, demonstrates an understanding of the epidemiology of hypertension, identifies health determinants related to this problem, and examines the concepts of prevention and its future implications.

Historical Background of Hypertension

Hypertension was recognized as a disease in official clinical terms when its first measurement device, called a "sphygmographic" instrument, was invented (Kotchen, 2011). Some initial cases of high blood pressure were reported by U.S. medical insurance companies in 1906. Using this device, it was verified that the persistence of both systolic and diastolic blood pressure existed. Standardized conditions for measuring blood pressure were developed by 1918; however, between 1925 and 1979, the Actuarial Society of America identified several factors related to hypertension in the U.S. population that required closer study. An age-related increase in hypertension was observed, as the 1925 study showed that younger women had lower blood pressure than men of the same age. Pulse pressure was found to increase in both sexes with age. Another notable finding was that blood pressure increased with body size and average weight in men, with limited data yielding similar patterns in women.

In subsequent years, studies benefited from improved blood pressure measurements. A 1939 report predicted that systolic blood pressure was a greater contributor to death among individuals over 40 years of age than diastolic blood pressure. Studies from 1959 again confirmed that blood pressure rises with age and weight in both sexes, and that mortality increased alongside higher blood pressure. Women over 40 had higher rates of hypotension but lower mortality rates. By 1979, studies indicated that mortality associated with overweight status was at the borderline for hypertensive men. Excessive mortality also resulted from hypertension-related conditions such as coronary disease, cerebral hemorrhage, and kidney and heart disease.

As studies expanded over time, factors such as ethnicity and racial group differences were incorporated. It was confirmed that blood pressure detected in children is likely to persist through adolescence and adulthood. In 1993, more than 350,000 men participated in the Multiple Risk Factor Intervention Trial, which showed that a systolic blood pressure of 120 mm Hg had a significant influence on coronary heart disease and end-stage renal disease. These findings were reinforced by a 2001 study demonstrating that excess deaths were associated with high blood pressure, including stage 1 hypertension, in men.

A major achievement in the history of this issue was the success of pharmacological treatment of hypertension, which affects more than one billion people (Saklayen & Deshpande, 2016). This success was compared in scope to advances associated with antibiotics, vaccinations, and oral rehydration therapy for infectious and diarrheal diseases. Research over time has provided valuable insights into the treatment of this common illness through the identification of genetic variants and therapeutic strategies. Setbacks have included failure to prescribe appropriate medications for hypertensive patients — particularly those with comorbidities — along with the high cost of drugs, clinician underestimation of antihypertensive therapy benefits, insufficient patient education, "white coat" hypertension, uncontrolled obesity, and complex drug combinations with adverse effects (Oparil & Calhoun, 1998).

Roles of Public Health Organizations

Everyone has a role to play in preventing and controlling high blood pressure or hypertension, including governments, policymakers, health workers, academic researchers, civil society, and the private sector — particularly food and beverage companies whose products, such as alcohol, contribute to elevated blood pressure (World Health Organization, 2020a). Although hypertension is considered one of the more treatable chronic non-communicable diseases, it still kills approximately 9.4 million people worldwide annually, with only 13 percent of those affected achieving adequate control globally (Angell, Cock & Frieden, 2016). That study concluded that low- and middle-income countries capable of managing diseases like HIV would likely be able to regulate hypertension as well, provided that health systems adopt strategies such as standardization through public health approaches, simplification by focusing on core interventions, and centralization to ensure delivery of treatment through community workers, nurses, and similar personnel.

A framework for hypertension treatment was created through the collaboration of the Pan American Health Organization (PAHO) and the U.S. Centers for Disease Control and Prevention, designed to be flexible enough for worldwide use. The PAHO strategic fund established purchase agreements enabling patients to obtain five of the six prescribed essential drugs. This fund also improved access to combination pills while applying quality assurance throughout pharmaceutical procurement processes at the national level. The Global Standardized Hypertension Treatment (GSHT) project ensures that delivery elements are addressed, including patient registries, standardized treatment guidelines, and task sharing within care teams. Hypertension registries established in the U.S. resulted in system-level improvements for approximately 600,000 patients. The World Health Assembly endorsed a set of global voluntary targets for non-communicable diseases in 2013, after which a 25 percent reduction in blood pressure prevalence was observed. If this trend continues through 2025, the number of people worldwide with uncontrolled or untreated cardiovascular disease attributable to high blood pressure is expected to be significantly reduced.

Governments around the world are additionally enacting policies to reduce salt content in food, given the established link between high sodium intake and hypertension. In the U.K., the government collaborated with food manufacturers to lower salt content across 85 categories of processed and packaged foods (Angell et al., 2014). The United States, Canada, Australia, Brazil, and Colombia have adopted similar strategies, with results showing that reducing salt content in bread from 2 percent to 1.4 percent has measurably lowered blood pressure levels in those populations.

A study conducted by Allen et al. (2016) among underserved U.S. populations revealed that community health workers play a crucial role in preventing and controlling hypertension. They work closely with health providers and assist in delivering important information to patients, particularly in overcoming barriers to medication adherence, through individual clinical meetings or home visits when necessary.

The academic and professional community also plays a critical role in hypertension prevention. Educational training of physicians, nurses, and health workers has been shown to improve disease control. A study by Zweifler et al. (1998) demonstrated that education using simulated patient instructors (SPIs) improved physicians' counseling skills with hypertensive patients, producing better medical communication outcomes than students still in the preparatory stage, with positive effects on testing, treatment, and follow-up practices.

Civil society — especially family members — is equally important in hypertension prevention. A study conducted in Western Nigeria among 360 hypertensive respondents found that family support had a meaningful impact, with a blood pressure control rate 46.4 percent higher than in previous local studies (Ojo, Malomo & Sogunle, 2016). Personal education about hypertension and healthy lifestyles also has encouraging effects on blood pressure control (Beigi et al., 2014). Lifestyle changes, increased physical activity, home blood pressure monitoring, reinforcement of health behaviors such as eating more fruits and vegetables and reducing sodium intake, and continuous follow-up care have all been reported to reduce blood pressure levels.

Epidemiology of Hypertension

Despite modern medical interventions for hypertension prevention, high blood pressure remains a leading cause of disease and disability globally. The World Health Organization (WHO) has reported that hypertension is most prevalent in low- and middle-income countries, with the highest rates in the WHO African region (27 percent) and 18 percent in the WHO American region (World Health Organization, 2019b). The existing trend showed an increase from 594 million to 1.13 billion affected individuals in low- and middle-income countries between 1975 and 2015. The percentage of people recommended antihypertensive medications — including Whites, Blacks, Asians, and Hispanics — was calculated using the 2017 ACC/AHA guidelines (Muntner et al., 2018). Overall, 31 percent of U.S. adults were eligible for antihypertensive medication, comprising 32 percent of men and 30 percent of women. By age group, this included 14 percent of those aged 20–44 years, 22 percent of those aged 45–54, 41 percent of those aged 55–64, 87 percent of those aged 65–74, and 100 percent of those aged 75 and older. By race, the distribution was 32 percent Whites, 27 percent Blacks, 27 percent Asians, and 33 percent Hispanics.

Blood pressure is recognized as a major risk factor for cardiovascular disease (Rahimi, Emdin & MacMahon, 2015). A log-linear relationship was demonstrated between blood pressure and vascular mortality across all blood pressure levels. A 20 mm Hg lower systolic blood pressure (SBP) was associated with a hazard ratio of 0.60 for mortality. Sex-based differences were modest, with a slightly lower mortality reduction per 20 mm Hg of lower SBP observed in men compared to women. Based on ethnicity, the risk of heart disease was higher and more prevalent among older Australian and Asian populations than among younger ones, while the impact of stroke was greater in Asia than in Australia, with stroke type varying by region across Europe, the U.S., Australia, and Asia.

Additional associations were studied through the Cardiovascular Research using Linked Bespoke Studies and Electronic Records (CALIBER) project. The age group of 30 to 59 years was linked to stable angina and ischemic stroke, while individuals above 80 years also faced similar risks. Racial differences in hypertension were identified, with Black men showing a 43 percent hypertension rate compared to 34 percent in White men, and Black women showing a 45 percent rate compared to 31 percent in White women — attributable mainly to differences in antihypertensive therapy access and environmental pressures (Rahimi, Emdin & MacMahon, 2015). Socioeconomic status, education, income, race, and geographic location (rural versus urban) further shape the distribution of high blood pressure.

Other major risk factors include consumption of an unhealthy diet, excessive sodium intake, diets high in saturated fats, insufficient consumption of fruits and vegetables, stress, low physical activity, excess alcohol and tobacco use, and obesity (World Health Organization, 2019b). Clinical indicators include morning headaches, irregular heart rate, changes in vision, nosebleeds, and ear buzzing. Serious manifestations can include nausea, vomiting, exhaustion, anxiety, chest pain, and muscle tremors.

The predictive power of systolic blood pressure is greater than that of diastolic blood pressure for stroke mortality. It has been noted that different studies yield different results depending on the age distribution of their participants. Among men aged 45 to 57 years, cardiovascular mortality risk grew with a given SBP rate, while in men aged 35 to 45 years, pulse pressure decreased at a given SBP rate, indicating increased cardiovascular risk in older men compared to younger ones.

According to WHO, hypertension can be mitigated by reducing salt intake to less than 5 grams per day (World Health Organization, 2019b). Reducing alcohol and tobacco consumption, increasing intake of fruits and vegetables, and maintaining daily physical activity are additional preventive measures. Personal management steps for hypertensive patients include managing mental stress, regularly monitoring blood pressure, and adhering to antihypertensive medications. Globally, prevention efforts include distributing antihypertensive medicines at reduced cost to make them accessible across income groups; however, these preventive measures remain highly dependent on the income levels of individual countries (Rahimi, Emdin & MacMahon, 2015). Hypertension disproportionately affects African Americans, middle-aged and older individuals, and socioeconomically disadvantaged populations. The southeastern United States has the highest regional rates of hypertension, while in China, northern states carry a higher burden than southern ones (Whelton, 2015). Studies in Europe, Africa, the Arabian Peninsula, and North Africa confirmed that hypertension rates depend on factors such as body mass index, diet, physical activity, and environmental conditions. Awareness, treatment, and control strategies have improved over time, though more country-wide intervention is still needed in the U.S., England, and Japan. For individuals aged 35 to 84 years, hypertension control improved between 1980 and 2009 by rates of 59 percent, 32 percent, and 25 percent, respectively.