The intruders’ succinct overview of Hypertension by Chandan Banerjee and Elija Gayen

https://youtu.be/LC0-iBeaAMw The intruders’ succinct overview of Hypertension 

Chandan Bandyopadhyay and Elija Gayen 

Abstract

Hypertension is a worldwide risk factor for cardiovascular disease burden and mortality. It is a disease related to risky health behaviors, including smoking, poor diet, overweight and obesity, alcohol consumption, physical inactivity and occupational lifestyle. The perception of hypertension by the individual also plays an important role in changing lifestyle and risky health behaviors. Some risk factors for hypertension are modifiable, such as smoking, diet, and overweight, whereas some are not modifiable, such as old age and genetic predisposition. Changing modifiable risk factors may result in a reduced burden of hypertension, and people have to know that they are at risk of hypertension to be able to make voluntary lifestyle changes. However, there are many barriers to such awareness in rural and minority populations, including lack of formal school education, communication gaps, and inaccessibility to routine health education programs. Many studies have reported the prevalence of hypertension and its risk factors, but few have paid attention to the prevalence of knowledge regarding hypertension and its associated risk factors in their study populations.

  Key words: hypertension, knowledge, risk factors,

Background

Hypertension is one of the most commonly treated conditions in modern medical practice, but despite its long history, it was largely ignored until the midpoint of the 20^th century. From a layman’s point of view, we will review the origins of elevated blood pressure from when it was first appreciated in 2600 BC to its most recent emerging treatments. Awareness of sustained elevations in blood pressure goes back to the Chinese Yellow Emperor’s Classic of Internal Medicine (2600 BC); even then, salt was appreciated as a contributor to elevated pressure. Early treatments included acupuncture, venesection, and bleeding by leeches. About 1000 years later, the association between the palpated pulse and the development of heart and brain diseases was described by Ebers Papyrus (1550 BC). In the early 1800s, Richard Bright’s work led to a link between myocardial hypertrophy and the presence The American Heart Association celebrates its 100th anniversary in 2024. This article is part of a series across the entire AHA Journal portfolio written by international thought leaders on the past, present, and future of cardiovascular and cerebrovascular research and care. To explore the full Centennial Collection, visit https://www. ahajournals.org/centennial

But really, it has only been since well after World War II that hypertension has finally been appreciated as the cause of so much heart, stroke, and kidney disease. The development of effective treatments for hypertension while acknowledging that so many people with hypertension in need of treatment have unacceptably poor. We explore why, despite our considerable and growing knowledge of hypertension, it remains a significant public health problem globally.

The 4600+ Years of History for the term Hypertension

Awareness of sustained elevations in blood pressure (Chinese Yellow Emperor’s Classic of Internal Medicine (2600 BC).

Egyptian physicians noted the association between the palpated pulse and heart and brain disease development (1550 BC).

William Harvey focused on how blood circulation occurred (1628 AD).

English clergyman Stephen Hales invented a manometer to measure arterial pressure in a horse (1733 AD).

Bright’s work linked myocardial hypertrophy and kidney disease (Bright’s disease; 1836 AD).

George Johnson, William Senhouse Kirkes, and Ludwig Traube suggested that the adaptations of thickened renal blood vessels and left ventricular hypertrophy resulted from elevated blood pressure (1850–1856 AD).

Samuel Wilks noted that left ventricular hypertrophy and diseased arteries were not necessarily associated with diseased kidneys. The first report of elevated blood pressure in a person without kidney disease was made by Frederick Mahomed (1874 AD) using a sphygmograph.

Sir Clifford Allbutt championed hypertension as a generalized circulatory disease with the term hyperpiesia (1896 AD). In the same year, the invention of the cuff-based sphygmomanometer by Riva-Rocci (1896 AD).

The term hypertension was born in 1896.

• Introduction Blood Pressure- isthe pressure exerted by circulating blood upon the walls of blood Vessels-decreases as the circulating blood moves away from the heart- expressed in terms of the systolic pressure over diastolic pressure (mmHg). If you listen to your heartbeat, it makes a lub dub sound. The lub is when blood is pushed out of the heart into the body and the dub is the reloading of the heart with more blood ready to push it out to the body Blood pressure is an important characteristic of our body. Without blood pressure, nutrients, oxygen, and proteins could not travel from the arterial side of the body to the venous side.
• Discuss about Blood Pressure Explain High Blood Pressure/ Hypertension in detail Classify Hypertension and Causes Explain the Consequences of Hypertension Discuss the regulation of Hypertension Explain Treatment of Hypertension Blood pressure is an important characteristic of our body. Without blood pressure, nutrients, oxygen, and proteins could not travel from the arterial side of the body to the venous side.

Normal Blood Pressure 95/65 mmHg=1 Years 100/65 mmHg=6-9 years 110/65-140/90mmHg= Adults -its Average Physiologic Value (normal BP) = 120/80 mmHg

If blood pressure is chronically elevated a condition is known as hypertension According to medical dictionary, hypertension means "High blood pressure; transitory or sustained elevation of systemic arterial blood pressure A consistent blood pressure of 140/90 mm Hg or higher is considered high blood pressure.

ToR (Terms and Reference) Hypertension

•        Isolated Systolic Hypertension is Systolic BP elevation in the absence of

elevated diastolic Blood Pressure.

•        Isolated Diastolic Blood Pressure is Diastolic BP elevation in the absence

of Systolic BP.

•        Isolated Systolic Hypertension is Systolic BP elevation in the absence of

elevated diastolic Blood Pressure.

•        Isolated Diastolic Blood Pressure is Diastolic BP elevation in the absence of Systolic BP.

Classification of Blood Pressure for Adults =>18 Years old

 

Category	Systolic mmHg	Diastolic mmHg
Hypotension	<90	>90
Desirable / Normal	90 to 119	60 to 79
Prehypertension	120 to 139	80 to 89
Stage 1 / Mild Hypertension	140 to 159	90 to 99
Stage 2 / Mild Hypertension	160 to 179	100 to 109
Stage 3/ Hypertensive Crisis / Severe / HYN	=> 180	=> 110

 

Ø  Types of Hypertensions:

Ø  Pulmonary Hypertension is abnormal elevation of pulmonary artery BP.

Pulmonary blood pressure is normally a lot lower than systemic blood pressure.

Ø  Normal pulmonary-artery pressure is about 14 mm Hg at rest.

Ø  If the pressure in the pulmonary artery is greater than 25 mm Hg at rest and

30 mm Hg during exercise, it is abnormally high and is called pulmonary hypertension.

Ø  Broadly Classified as Primary or Secondary Hypertension. Primary pulmonary hypertension;

Ø  When not accompanied by underlying heart and lung disease or other illnesses, it is called primary pulmonary hypertension.

Secondary pulmonary hypertension

If a pre-existing disease triggered the PHT e.g. Congenital heart defects Intra-cardiac left-to-right shunts: Heart valve conditions: mitral stenosis.

Typically, "blood pressure," "high blood pressure" and "hypertension" refer to the systemic pressure throughout your body. Hypertension is classified as, primary (essential) Idiopathic / hypertension or secondary hypertension.

a)    Primary or Essential Hypertension About 90–95% of cases are categorized as "primary hypertension," which means high blood pressure with no obvious/direct medical cause.

b)    Although no direct cause has been identified, there are many factors such as sedentary lifestyle, smoking, stress, visceral obesity, salt (sodium) sensitivity, alcohol intake, and vitamin D deficiency, aging, some inherited genetic mutations and having a family history of hypertension, an elevated level of renin, sympathetic nervous system over activity…etc. increase the risk of developing primary hypertension.

c)    Secondary Hypertension: About 5–10% of cases (Secondary hypertension) are caused by other conditions that affect the kidneys, arteries, heart or endocrine system. Thus, results from an identifiable cause. but: may come to normal values by treatment.

d)    This type is important to recognize since it's treated differently to essential hypertension. Factors that cause this type of HYN 1. Adrenocortical hyperfunction Primary hyperaldosteronism CushingSyndrome Congenital or hereditary adrenogenital syndromes):

e)    Pheochromocytoma and Severe Polycythemia.

f)     Renal Diseases It is common for all types of chronic kidney disease to eventually cause hypertension (approx. 80% of chronic kidney disease patients develop hypertension at some point). This is due to fluid retention in the body, due to poor elimination of fluids and poor control of sodium.

g)    Glomerulonephritis (chronic renal inflammation) Polycystic renal disease-is cystic genetic disorder of the kidneys Tumors of JG Cell- Renin-producing tumors Renovascular stenosis or renal infarction (Reno vascular hypertension) - RAS Hyperparathyroidism and Calcium overload leads to renal failure and hypertension.

h)   Neurogenic hypertension Polyneuritis (lead poisoning) inflammation of Peripheral nerves Increased intracranial pressure Arterial occlusion Tumors.

i)     Others BP in upper parts of body, i.e. above Coarctation of aorta obstruction. Hypercalcemia Medications, e.g., glucocorticoids etc.

j)     Consequences of Hypertension: Organ Damage.

k)    Transient ischemic attack, stroke;

l)     LVH (left ventricular hypertrophy); CHD (coronary heart disease); CHF (congestive heart failure);

m)  Retinopathy;

n)   Peripheral arterial disease;

o)    Chronic kidney disease;

Regulation of HBP/HPN

Blood Pressure is regulated within a narrow Range If the blood pressure is too low: Inadequate perfusion of organs If the Blood pressure is abnormally high: Heart diseases, vascular diseases, strokes;

The Baroreceptor reflex functions to restore blood pressure back to normal values whenever the blood pressure deviates from the normal range. The homeostatic mechanism involves a negative feedback loop to minimize and oppose any changes in Blood pressure. i.e. an increase in BP reflexively causes the BP to decrease and vice versa.

What is a Baroreceptor?

Baroreceptors are specialized nerve endings, or mechanoreceptors, that detect changes in blood pressure. They primarily function to maintain blood pressure within a healthy range by relaying pressure information to the brain, which then adjusts heart rate and blood vessel constriction/dilation. These receptors are found in key locations like the carotid sinus and aortic arch. 

 

Prevention and Treatment of Hypertension: ACE Inhibitors Drugs inhibit the enzyme converting angiotensin into angiotensin II which acts as vasodilators of both resistance and capacitance vessels. Thus, blood vessels relax and blood flows freely.

Angiotensin II receptor blockers: Diuretics work on the kidney to remove excess water and fluid from body to lower BP.

Beta blockers:

Competitively inhibit the binding of catecholamines to beta-adrenergic receptors Calcium Channel Blockers- Decrease calcium influx into cells of vascular smooth muscle-causes the blood vessel to relax and widen. Nervous system inhibitors- slow nerve impulses to the heart. Vasodilators- cause blood vessel to widen, allowing blood to flow more freely. Alpha Blocker- blocks an impulse to the heart causing blood to flow more freely.

 

•      Minimize Alcohol: Alcohol raises blood pressure and can harm liver, brain, and heart

•      Quite Smoking/ Stop

•      Smoking damages blood vessel walls and causes early hardening of the arteries. Nicotine narrows your blood vessels and forces your heart to work harder Be Physically Active/Exercise.

•      Blood pressure rises as weight rises. Obesity is also a risk factor for heart disease.

Globally, the overall prevalence of raised blood pressure in adults aged 25 and over was around 40% in 2008. The number of people with hypertension rose from 600 million in 1980 to nearly 1 billion in 2008. The prevalence is significantly higher in geriatric population. Worldwide, raised blood pressure is estimated to cause 7.5 million deaths, about 12.8% of the total of all annual deaths. Raised blood pressure is a major risk factor for coronary heart disease and ischemic as well as hemorrhagic stroke. Blood pressure levels have been shown to be positively and progressively related to the risk for stroke and coronary heart disease. In some age groups, the risk of cardiovascular disease doubles for each incremental increase of 20 / 10 mmHg of blood pressure, starting as low as 115 / 75 mmHg. In addition to coronary heart diseases and stroke, complications of raised blood pressure include heart failure, peripheral vascular disease, renal impairment, retinal hemorrhage and visual impairment. Treating high systolic blood pressure and diastolic blood pressure so they are below 140 / 90 mmHg is associated with a reduction in cardiovascular complications. Blood pressure can be managed with drugs as well as weight reduction, salt restriction, eating fruits and vegetables, etc. Non-pharmacological measures play an important role in management of hypertension. The present study was done to assess knowledge of hypertension and its associated risk factors.

Conclusion:

Because hypertension is emerging as a major public health problem in many developing countries undergoing epidemiological transition, it is essential to gather both epidemiological and knowledge and awareness data on hypertension as crucial steps in the design of sound prevention and control programs. It is particularly important to maximize the efficiency of such programs in these countries to minimize delay in achieving effective hypertension control.

This study provides an insight about the level of knowledge regarding one of the most globally concerned diseases among urban slum residents was alarmingly low. People are still not aware about the risk factors associated with hypertension. Promoting public education in such urban slums would be beneficial for raising community awareness and changing health risk behaviors. It is urgently necessary to promote knowledge, awareness, and health literacy among urban slum residents to prevent hypertension and associated CVDs.

References:

1. Pearson International Edition Human Physiology An Integrated Approach 5^th Edition. DEE UNGLAUB SILVERTON.
2. www.americanheart.org/presenter.jhtml?identifier “High Blood Pressure”.
3. Different internet sources 
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6. Gupta R, Pandey RM, Misra A, et al. High prevalence and low aware­ness, treatment and control of hypertension in Asian Indian women. J Hum Hypertens. September 1, 2011. [Epub ahead of print.]
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8. Aubert L, Bovet P, Gervasoni JP, Waeber B, Pacccaud F, Knowledge, Attitudes, and Practices on Hypertension in a Country in Epidemiological Transition, Hypertensionhyper.ahajournals.org,1998; 31: 1136-1145

Authors Details:

Chandan Bandyopadhyay presently employed in a Sate owned PSU in West Bengal; is an author, researcher, motivator, traveler and photographer and fascinated by the power of mind.

Elija Gayen is an author-illustrator, traveler, photographer and a vivid reader of Bengali literature but not an avid one; was a daydreamer in high school, and, unsure of future goals, went to self-train at different fields of technology, culinary and languages; graduated from the Jadavpur University in Civil Engineering in 1995; presently engaged in making stories from a pretty little apartment in the old city of Berlin in Germany and for bread and butter employed in an ITes.

Both the authors are obsessed with self-improvement; personal mission is to help people realize their potential and reach higher levels of consciousness without causing harm to fellow people or the nature.

We respect different socio-cultural-ethnic group across the world despite of their caste, creed and financial and so called social status.   

N.B.: If interested, for a detailed version, please contact to: weism09022025@gmail.com