High Blood Pressure: The Silent Killer

Understanding Hypertension

Hypertension, also known as high-blood pressure, is a disease that, according to the American Heart Association (AHA), has been diagnosed in 74.4 million Americans (American Heart Association, 2014). AHA also tells us that serious health consequences occur when hypertension is left untreated. An examination of how hypertension impacts the body shows how this disease can progress without symptomatology and can kill without warning.

What is Hypertension?

Hypertension is a chronic medical condition where blood pressure increases due to constriction of arteries. The normal rand of blood pressure is measured using two metrics: systolic and diastolic pressure. These measurements are dependent on the contraction of the heart muscle. When the heart muscle is contracting this measurement is known as systolic. When the measurement of blood pressure is taken between beats of the heart or when the heart is relaxed this is known as diastolic. The measurement is produced with the maximum (systolic) over the minimum (diastolic) pressure (American Heart Association, 2014). This measurement is compared with what is considered the average range for a person and this makes the determination of high blood pressure.

There are several categories of hypertension that are identified by their systolic and diastolic ranges.

In general, the normal range of blood pressure at rest is within the range of 100–140 mmHg systolic and 60–90 mmHg diastolic. High blood pressure is considered to be in the range of 140/90 mmHg and above. In this range, blood pressure needs to be controlled (American Heart Association, 2014).

There are two forms of hypertension known as primary hypertension and secondary hypertension. The majority of cases of hypertension, 90–95% are diagnosed as primary. Primary hypertension is defined as being high blood pressure that has no apparent medical cause. All secondary cases of hypertension are caused by diseases or conditions “relating to the kidneys, arteries, heart, or endocrine system.” (American Heart Association, 2014)

Causes

There are many factors that impact a person’s blood-pressure at any given time including: family history, lifestyle, diet, stress levels and ethnicity. All of these factors contribute to determine one’s blood-pressure. Family history of high blood-pressure is an important factor because this factor increases one’s chances statistically of developing hypertension.

Lifestyle is another factor which has been linked to the risk of hypertension. A sedentary lifestyle can greatly increase the risk for hypertension (WebMD, 2014). In research of hypertension exercise was found to be an enormous factor in reducing the risk of the disease. It was found that people who exercise could lower their blood pressure significantly. Cardio exercise such as walking or cycling for 30–45 minutes 3 times per week reduced systolic blood pressure approximately10 mm Hg (American Heart Association, 2014).

As well, poor diets also increased hypertension risk (Yokoyama, et al., 2014). Sodium is large risk factor in hypertension. About 50% of people with hypertension are sensitive to salt. Low salt diets reduce blood pressure in individuals with hypertension. The reasons for low slat diets are steeped in controversy. While these diets appear to reduce hypertension the reason for this is not clear. It may be that salt interactions with potassium may create imbalances in the body and cause increased blood pressure. According to the American Heart Association it is important to maintain a diet with potassium for controlling blood pressure because potassium reduces the impact of sodium: an average adult should be about 4,700 milligrams per day (American Heart Association, 2014).

Stress and hypertension also seem to go hand in hand but not in a direct causal manner. There is no direct link between stress and hypertension but it is believed that stress causes other activities which increase the risk of hypertension. For example, eating poorly and using drugs and alcohol are often caused by stress. The use of substances in this manner can increase blood pressure, especially alcohol (American Heart Association, 2014).

Another factor that seems to be related to hypertension is ethnicity. Some ethnic groups such as African Americans and Asians seem to have an increased prevalence. There are numerous studies which seem to confirm this finding, “Black people clearly have a higher prevalence than … white people,” and another study, “reported twice as much hypertension in black and Asian people” (Brown, 2006).

Understanding hypertension and what it is extremely difficult because of the number of biochemical interactions which are taking place in hypertension patients. There are many changes in chemistry that there are different types of screening that measure different chemical levels. The most comprehensive screening is known as chem-20, SMA-20, or SMAC-20. This test examines 20 different chemicals in the blood. The comprehensiveness of this test is due to the fact that the asymptomatic nature of hypertension does not always present itself in sodium or potassium levels. This highlights the fact that knowledge concerning hypertension is still limited and warrants further study.

Symptoms

There is little symptomatology exclusive to hypertension (National Institute of Health, 2012). The lack of symptomology makes hypertension a dangerous condition because it often goes unnoticed until too late. Headache is often associated with hypertension but is not always present (National Institute of Health, 2012). Elevated sodium levels is another symptom of hypertension (National Institute of Health, 2012).

Stress is perhaps the most common symptom but along with the other symptoms mentioned this may or may not be present (National Institute of Health, 2012).

The only time that symptoms are clearly present is when a person enters a state known as hypertensive crisis. Hypertensive crisis occurs when blood pressure readings spike dangerously. In this state, the systolic reading will be 180 or higher. The diastolic reading will be 110 or higher. This state presents several obvious symptoms including severe headaches, anxiety, shortness of breath, and nosebleeds (American Heart Association, 2014).

When a person is in a hypertensive state, they will need immediate emergency medical help in order to bring blood pressure down. This condition can be fatal if not treated immediately.

The Impact of Hypertension on the Body

Hypertension has a severe impact on body. Damage to the inner lining of arteries prompts a homeostatic response from the body to thicken and stiffen the walls of the arteries. This process is referred to as arteriosclerosis (American Heart Association, 2014). The hardening or stiffening of the left ventricle makes it difficult for the heart to pump blood through the body which is known as Left Ventricle Hypertrophy which causes heart attack, heart failure, or sudden cardiac death.

Another dangerous impact on the body is the threat of aneurysm. Too much pressure on the arteries going through brain can cause the blood vessels to rupture causing a brain aneurysm (American Heart Association, 2014). Aneurysm has a high mortality rate with more than forty percent of sufferers not surviving twenty-four hours, and another twenty-five percent will die within six months (Natioinal Institute of Nurological Disorders and Stroke, 2014).

A stunning seventy-seven percent of Americans who are admitted to a hospital for their first stroke have blood pressure over 140/90 (WebMD, 2014). Sixty nine percent of Americans who are having their first heart attack also have blood pressure over 140/90 (WebMD, 2014). Seventy-four percent of Americans who are admitted to a hospital with congestive heart failure have blood-pressure over 140/90 (WebMD, 2014). Managing hypertension and avoiding this problem is not a simple decision for many people as it is a lifestyle change.

References

American Heart Association. (2014, September 4). About High Blood Pressure. Retrieved from American Heart Association: http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodPressure/About-High-Blood-Pressure_UCM_002050_Article.jsp

Brown, M. J. (2006 , April 8). Hypertension and ethnic group. Retrieved from National Institute of Health: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1432176/

Natioinal Institute of Nurological Disorders and Stroke. (2014). Cerebral Aneurysms Fact Sheet. Retrieved from Natioinal Institute of Nurological Disorders and Stroke: http://www.ninds.nih.gov/disorders/cerebral_aneurysm/detail_cerebral_aneurysms.htm

National Institute of Health. (2012, August 2). What Are the Signs and Symptoms of High Blood Pressure? Retrieved from National Institute of Health: https://www.nhlbi.nih.gov/health/health-topics/topics/hbp/signs.html

WebMD. (2014). Slideshow: A Visual Guide to High Blood Pressure. Retrieved from WebMD: http://www.webmd.com/hypertension-high-blood-pressure/ss/slideshow-hypertension-overview

Yokoyama, Y., Nishimura, K., Barnard, N. D., Takegami, M., Watanabe, M., Sekikawa, A., . . . Miyamoto, Y. (2014). Vegetarian Diets and Blood Pressure A Meta-analysis. JAMA Intern Med., 174(4), 577–587.