, also referred to as high blood pressure, is one is oneof the most common chronic medical conditions around the world. Thecondition is characterized by elevated pressure in blood vessels inthe body. Elevated blood pressure is anything more than 120 over 80(120/80). The condition is a risk factor for stroke andcardiovascular conditions especially in left unattended for long. Thecondition has been a subject of medical research for long with viewsto discover a cure. As such, the predisposing factors and the majorcauses have received higher attention. Where doctors can identify theactual cause of an elevated blood pressure, it is categorized asecondary while where doctors fail to determine the actual cause ofelevated pressure, it is categorized as primary. Primary hypertensionaccounts for 90% of cases. A combination of environmental and geneticfactors is the main cause of hypertension. A number of genes arethought to play a key role in this. This paper looks at the geneticcauses of primary hypertension and also discusses the symptoms,treatment, prevalence and prevention of the disease in the US andaround the world.
Studies on hypertension have revealed that the condition ishereditary and occurs in families. It has been recorded in parentoffspring relations, natural adopted children and in discordant andconcordant twins. However, genetics contribute only 30-50% of thevariation in blood pressure. This means that environmental factorssuch as diet and lifestyle combine at different levels and indifferent ways to impact blood pressure variation uniquely. It isbelieved that hypertension is just the tip of the iceberg in terms ofthe mechanism that results in blood pressure variation (Weder, 2007).Part of this mechanism takes place in the kidney while the othertakes part outside the kidney (Butler, 2010). It is believed thatmolecular-pathophysiologic mechanisms affect the functioning of thebody to cause hypertension. There
Since the invention of molecular genetic technology, researchers havebeen able to identify genes responsible for transmitting geneticdiseases. Over a hundred genes have been identified to be involved inthe transmission of a variety of genetic illnesses among themhypertension (Agarwal, Williams & Fisher, 2005). The approach toidentify the particular genes responsible for transmission ofhypertension has taken three main approaches namely: mendelian formsof hypertension, candidate gene approaches, and genome-wide scanningstrategies (Butler, 2010).
The exact numberof genes involved in the causation and transmission of hypertensionare currently exceeds 30. As of 2005, the list of genes hypothesizedto cause hypertension and the degrees of association is listed ontable 1. Recent studies have identified several genes with as much as11 new genes added to the list by a study from Queen Mary Universityof London (Eleven new genes, 2014).
Table1 Genes associated with hypertension
The genes are noted to have additive effects on each other. Thismeans that each hypertension associated gene contributes to the loweror elevation of BP. However, this situation is not as simplified assuggested by the statement. This is because each gene interactsuniquely with varying environments. This has been proven by exposingindividuals with different genetic components to a similarenvironment the result being that the individuals respondeddifferently. The most common and basic environment that nearly allassociated genes have shown to function robustly is that of highsodium or salt intake.
is most common in persons over 60 years old. It affects25-35% of the adult population in the developed world (CDC, 2013). Inthe US, the figures are reported at 24% (Franceschini et al 2012).According to the World Health Organization (WHO), the figure stood at40% of the global population as of 2008. The number of people withhypertension is expected to grow with the increased life expectancyespecially in the developed world. The shaper rise from a globalpopulation of hypertensive patients of 600 million in 1980 to nearlyone billion in 2008 shows that as diagnoses and life expectancygrows, the figures can only grow. The Americas have some of the lowerrates of prevalence compared to global averages of 35% in both sexes.Middle income countries record higher prevalence rates, 40% than highincome countries, 35%.
The age groups that records the highest prevalence and risk is theover 60 years. This group accounts for 66.7% of the cases in the USfollowed by the 40-49 years groups at 30.4%.. By ethnicity, blacksaccount for the largest caseload at 40.4% followed by whites at 27.4%and Hispanics at 26.1%. (CDC, BP, 2014). A study by Grootveld etal. (2014) seeking to associate obesity with hypertension in athree ethnic groups showed that ethnicity only explained BP in part.Another study by CDC also shows that blacks, who happen to record thehighest hypertension cases despite their relatively smallerpopulation, also record the highest cases of obesity in the US at 51%of the cases. This proofs that obesity also plays significant role,probably more important one in prevalence of hypertension (CDCObesity, 2010).
Worldwide, raised blood pressure is estimated to cause 7.5 milliondeaths, about 12.8% of the total of all deaths. In Europe, thechronic disease is associated largely with cardiovascular diseasesincluding heart failure, coronary artery disease, myocardialinfarction, congestive heart failure, stroke and other diseases, suchas end-stage renal failure and are also present in metabolicsyndrome. To this into perspective, 40% of deaths are caused bycardiovascular diseases (Reuter, et al 2014).
is one of the trickiest conditions to diagnose becausepatients may not be aware of it. However, the use ofsphygmomanometer/blood pressure meter/sphygmometer can be used toaccurately measure blood pressure levels. The measurement is given intwo to representing diastolic blood pressure and systolic bloodpressure. Other that through the use of sphygmomanometer theconditions can present itself in form of severe headache or migraine,fatigue or confusion, blurred vision, labored breathing, chest pain,abnormal heartbeat or pulse,blood in the urine, pounding in yourchest, neck, or ears (WebMd, 2014))
As a chronic disease, the treatment of hypertension is only limitedto managing symptoms. The treatment of the illness usually takes atwo pronged approach. One of them is similar to the preventativemeasures which include modification on diet, body weight management,exercise, regulating alcohol intake and smoking plus lowering saltand fat intake. The second approach pertains to treatment usingmedication. There are several classes of drugs with differentfunctions in the body. It is important to note that the choice ofdrugs or combination of drugs used on given patient varies with age,race, preexisting conditions such as diabetes and interaction withother drugs (WebMd, 2014).
This class of medication targets the kidney and assists in easing theblood pressure by lowering the volume of blood in the system. They dothis by triggering the kidney to assume the body has excess fluidsand thus remove excess in form of urine. The common drugs include,Aldactone (spironolactone), Dyrenium (triamterene), Esidrix,Hydrodiuril, and Microzide (hydrochlorothiazide or HCTZ), Hygrotonand Thalitone (chlorthalidone), Lasix (furosemide), Lozol(indapamide), Midamor (amiloride hydrochloride), Mykrox and Zaroxolyn(metolazone) (WebMd, 2014).
Beta-Blockers and HighBlood Pressure
This class of drugs targets the heart. They function by slowing downthe pulse to reduce the blood pressure in the system. This is becauseincreased blood pressure results in the heart pumping hard to ensureblood accesses all body organs. Common beta blockers include,bocadren (timolol), Tenormin (atenolol), Visken (pindolol), Zebeta(bisoprolol fumarate), Normodyne, Cartrol (carteolol hydrochloride),Coreg (carvedilol), , Lopressor and Toprol XL (metoprolol), Sectral(acebutolol), Corgard (nadolol), Inderal (propranolol), Kerlone(betaxolol), Levatol (penbutolol sulfate) and Trandate (labetolol).
This class of drugs targets blood vessels. They function bytriggering the release of hormones that make blood vessels to relaxand enlarge to absorb elevated blood pressure. Common drugs includeCardura (doxazosin), Hytrin (terazosin) and Minipress (prazosin).
ACE InhibitorsThisclass of drugs target to inhibit the release of theangiotensin-converting enzyme. The drugs target the renin-angiotensinsystem in the regulation of blood pressure. This system regulatesblood pressure by maintaining a blood pressure and fluid balance.When blood volume or sodium drops or potassium is high, specializedkidney cells release an enzyme called renin. This renin converts ahormone angiotensinogen produced in the liver to angiotensin I.Another enzyme produced in the lungs converts angiotensin I toangiotensin II. This second hormone causes vasoconstriction henceincreased blood pressure. Angiotensin II also causes the release ofanother hormone aldosterone in the adrenal glands which causesretention of sodium and water while potassium is excreted in therenal tubules of the kidney. This allows the body to maintain aconstant blood pressure. When this system malfunctions, it causeshypertension and increases risk of heart failure and kidney failure(Luft, 2004).Oneof the drugs that utilizes this system in fighting hypertension isEdarbyclor. It contains an angiotensin II receptor blocker (ARB) anda thiazide-like diuretic. The angiotensin II receptor blockerprevents angiotensin II hormone from sending the signal to the kidneyto release hormone aldosterone which directly regulates fluid balancein the blood. Other drugs that target the system but only blockproduction of ACE are Accupril (quinapril), Altace (ramipril),Capoten (captopril), Mavik (trandolapril), Lotensin (benazepril),Monopril (fosinopril), Prinivil and Zestril (lisinopril), Univasc(moexipril) and Vasotec (enalapril) (WebMd 2014).
A balanced die if often recommended for healthy individual and patients of hypertension. For health y individuals, they should embark on taking healthy foods rich in fruits and vegetables and low in fat and salt. Salt increases the blood pressure through the kidney mechanism.
Individuals are also advised to regulate their alcohol consumption to acceptable elves. Acceptable levels in this case should be 3-4 units in men and 2-3 units maximum for women. Alcohol is presumed to pose a risk to development of hypertension due to the high calorie content that is likely to weight gain.
Caffeine should be avoided. These include caffeine contained in soft drinks such as coffee, cocoa and even in energy drinks. Individual should identify other sources of fluids for their body to avoid high intake of caffeine rich drinks.
Weight management and physical exercise. Individual should strive to achieve healthy weight identified through the BMI calculator. Being overweight causes the narrowing of blood vessels as a result of fat being deposited on the inner blood vessel walls. With the narrow blood vessels, blood pressure rises which also overworks the heart. Regular exercise is also recommended and not only to the overweight people but for all people. Physical exercise helps the body in burning excess calories and also exercises the and the blood vessels. About 2.5 hrs of moderate exercise such as cycling and aerobics is recommended every week.
Relaxation therapies. Several years back, hypertension was thought to be caused by tension. Consequently, relaxation practices were widely recommended and practiced as a treatment and prevention mechanism for the condition. In modern times, the use of relaxation practices has drawn wide criticism though it is still practiced especially through Cognitive Behavioral Therapy (CBT) strategies.
From the above discussion, it is clear the burden of hypertension canonly grow bigger. The fact the global population is aging rapidlyowing to improved health care only services to restate confirm thatthe number of affected persons can only grow. There is need formedical researchers and pharmaceutical companies to invest in moreresearch to identify a permanent cure to this condition that waspreviously thought to affect the rich only. Identifying the geneticcause of hypertension clearly will not only help families inaddressing the issue but will advise couples on the risks that theiroff springs face. It is also necessary to increase public awarenessand knowledge in management and prevention of the condition.Populations need to learn more about the need to eat healthy exerciseand live a healthy life not only for aesthetic purposes but also fortheir health. In some communities, there is also need to addresscultural issues that glorify certain lifestyles that predisposeindividual to the conditions. These include fatty meals associatedwith Americans and fast foods associated with the developed world.The preventative approach to managing the disease will decrease theburden of diseases and also lead to improved quality of life.
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