Diseases & Conditions

 

Hypertension

Diseases & Conditions

 

What is hypertension?

Hypertension or high blood pressure refers to the elevated pressure that blood applies to the inner walls of the arteries.

An individual's blood pressure is defined by two measurements:

  • Systolic pressure is the pressure in the arteries produced when the heart beats.
  • Diastolic pressure refers the pressure in the arteries when the heart rests between beats.

Blood pressure is reported as the systolic pressure over diastolic pressure. Normal blood pressure is below 120/80 mm Hg.

Over time, if the force of the blood flow remains high, the tissue that makes up the walls of arteries gets stretched beyond its healthy limit and damage occurs.1

Hypertension increases the risk of heart failure, heart attack, stroke, and kidney failure.

 

What causes hypertension?

There are two types of hypertension:2

  • Primary hypertension: This type of hypertension develops in patients over time and does not have a known cause.
  • Secondary hypertension: This type of hypertension is caused by another condition. Different conditions and medications can lead to secondary hypertension, including:
    • Sleep apnea
    • Chronic kidney disease
    • Tumors of the adrenal gland
    • Thyroid problems
    • Congenital heart disease
    • Certain medications, such as birth control pills, cold remedies, and decongestants
    • Illicit drugs, such as cocaine and amphetamines

 

What are the risk factors of hypertension?

Hypertension has many risk factors, including:

  • Older age: People over 60 years old are at higher risk of developing hypertension.
  • Race: Hypertension is more prevalent among blacks than whites.
  • Being overweight or obese
  • Gender: Men are more prone to develop hypertension at younger age than women.
  • Family history: Hypertension tends to run in families.
  • Chronic stress
  • Smoking
  • High salt intake: Sodium leads to fluid retention which will raise blood pressure
  • Low dietary potassium: Potassium can help balance out some of the harmful effects that high sodium intake can have on blood pressure
  • Physical inactivity

 

What are the symptoms of hypertension?

High blood pressure does not usually cause any symptoms. Rarely, headaches may occur. A patient can have hypertension for years without knowing it. During this time, the condition can damage the heart, blood vessels, kidneys, and other parts of the body.4

 

What are the complications of hypertension?

Hypertension can lead to serious complications if left untreated:5

  • Atherosclerosis: Atherosclerosis occurs when fatty plaques build-up inside the walls of the arteries leading to coronary artery disease. Untreated hypertension is a major cause of atherosclerosis.
  • Stroke: Untreated hypertension increases the likelihood of strokes.
  • Heart disease: The most serious health problem and major cause of death related to untreated high blood pressure is heart disease.
  • Kidney Disease: Patients who have hypertension are more likely to develop kidney disease and kidney failure.
  • Eye damage: Untreated hypertension can affect the sight damaging blood vessels in the retina.
  • Diabetes: Hypertension is a risk factor for diabetes and vice versa diabetes increases the risks of developing hypertension.
  • Preeclampsia: Hypertension can be a sign of preeclampsia which is a pregnancy-related problem that can become life-threatening.

 

How is hypertension diagnosed?

Hypertension is diagnosed using a blood pressure test. This test is done several times to make sure the results are correct. To measure the blood pressure, the doctor will use a gauge, a stethoscope, and a blood pressure cuff. A blood pressure reading is given in millimeters of mercury (mm Hg).

As defined by the American Heart Association, blood pressure measurements fall into four general categories. This blood pressure chart reflects the four categories:6

Blood pressure category

Systolic

mm Hg (upper #)

 

Diastolic

mm Hg (lower #)

Normal

Less than 120

and

Less than 80

Prehypertension

120 - 139

or

80 - 89

High blood pressure

(Hypertension) Stage 1

140  - 159

or

90 - 99

High blood pressure

(Hypertension) Stage 2

160 or higher

or

100 or higher

Hypertensive crisis

(Emergency care needed)

Higher than 180

or

Higher than 110

 

How is hypertension treated?

Treatment of hypertension includes lifestyle changes and medication to control blood pressure:7

  • Treatment of hypertension usually begins with lifestyle changes:
    • Reducing the amount of salt in diet
    • Losing weight for overweight or obese patients
    • Quitting smoking
    • Exercising at least 30 minutes per day most days of the week
    • Managing stress

 

  • Medications:
    • Diuretics: Diuretics reduce the amount of fluid in the blood lowering blood pressure.
    • Beta Blockers: These drugs help relax the heart muscle, slow the heart rate and decrease blood pressure.
    • Angiotensin-Converting Enzyme (ACE) Inhibitors: ACE inhibitors relax blood vessels and lower blood pressure to decrease the work of the heart.
    • Angiotensin II Receptor Blockers (ARBs): ARBs impede blood vessels from constricting or narrowing, which can lower the blood pressure.
    • Calcium Channel Blockers: These medications help relax the muscles of blood vessels.
    • Alpha Blockers: These medications reduce nerve impulses to blood vessels impeding them from narrowing and allowing blood to flow.
    • Alpha-Beta Blockers: These medications reduce nerve impulses the same way alpha blockers do. However, like beta blockers, they also slow the heartbeat. As a result, blood pressure goes down.
    • Central Acting Agents: These medications decrease nerve signals that narrow blood vessels lowering blood pressure.
    • Vasodilators: These medications prevent the arteries from narrowing.

 

 References

  1. Patient information: High blood pressure in adults (Beyond the Basics) (High blood pressure in adults) http://www.uptodate.com/contents/high-blood-pressure-in-adults-beyond-the-basics (Accessed January 12, 2016)
  2. High blood pressure (hypertension) (Causes) http://www.mayoclinic.org/diseases-conditions/high-blood-pressure/basics/causes/con-20019580 (Accessed January 12, 2016)
  3. (Medical News Today) http://www.medicalnewstoday.com/articles/150109.php?page=2 (Accessed January 12, 2016)
  4. (National Center for Biotechnology Information) http://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0024201/ (Accessed January 12, 2016)
  5. Hypertension: Symptoms & Types (WebMD) http://www.webmd.com/hypertension-high-blood-pressure/guide/hypertension-symptoms-types (Accessed January 12, 2016)
  6. Understanding Blood Pressure Readings (Understanding Blood Pressure Readings) http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodPressure/Understanding-Blood-Pressure-Readings_UCM_301764_Article.jsp#.VpS1fMZ97IU (Accessed January 12, 2016)
  7. How Is High Blood Pressure Treated? (- NHLBI, NIH) http://www.nhlbi.nih.gov/health/health-topics/topics/hbp/treatment (Accessed January 12, 2016)