Definition, Types, Risk factors, Pathogenesis, Complications, Diagnosis and Treatment of Hypertension

 Definition, Types, Risk factors, Pathogenesis, Complications, Diagnosis and Treatment of Hypertension .

DEFINITIONS:

Normal blood pressure – Systolic <120 mmHg and diastolic <80 mmHg

Elevated blood pressure – Systolic 120 to 129 mmHg and diastolic <80 mmHg

Stage 1 Hypertension – Systolic 130 to 139 mmHg or diastolic 80 to 89 mmHg

Stage 2 Hypertension – Systolic at least 140 mmHg or diastolic at least 90 mmHg

Types of Hypertension:

PRIMARY HYPERTENSION:

Hypertension without any know cause is called primary Hypertension. 

Risk factors for primary (essential) hypertension:

●Age – Advancing age is associated with increased blood pressure, particularly systolic blood pressure, and an increased incidence of hypertension.

●Obesity – Obesity and weight gain are major risk factors for hypertension and are also determinants of the rise in blood pressure that is commonly observed with aging.

●Family history – Hypertension is approximately twice as common in subjects who have one or two hypertensive parents, and multiple epidemiologic studies suggest that genetic factors account for approximately 30 percent of the variation in blood pressure in various populations.

●Race – Hypertension tends to be more common, be more severe, occur earlier in life, and be associated with greater target-organ damage in Black patients.

●Reduced nephron number – Reduced adult nephron mass may predispose to hypertension, which may be related to genetic factors, intrauterine developmental disturbance (eg, hypoxia, drugs, nutritional deficiency), premature birth, and postnatal environment (eg, malnutrition, infections).

●High-sodium diet – Excess sodium intake (eg, >3 g/day [sodium chloride]) increases the risk for hypertension, and sodium restriction lowers blood pressure in those with a high sodium intake.

●Excessive alcohol consumption – Excess alcohol intake is associated with the development of hypertension, and alcohol restriction lowers blood pressure in those with increased intake.

●Physical inactivity – Physical inactivity increases the risk for hypertension, and exercise (aerobic, dynamic resistance, and isometric resistance) is an effective means of lowering blood pressure.

●Insufficient sleep – Short sleep duration (eg, <7 hours per night) is associated with a higher risk of hypertension [21-23], and increasing the duration of sleep may lower blood pressure.

●Social determinants – Social determinants of health, such as low socioeconomic status, lack of health insurance, food and housing insecurity, and lack of access to safe spaces for exercise may underlie several of the above risk factors for hypertension (obesity, poor diet, physical inactivity, etc. These social factors likely account in large part for racial disparities in hypertension.

SECONDARY OR CONTRIBUTING CAUSES OF HYPERTENSION:

Hypertension with know cause is called secondary hypertension. 

Major causes of secondary hypertension include:

manifestations of Cushing syndrome".)

●Oral contraceptives, particularly those containing higher doses of estrogen

•Nonsteroidal antiinflammatory agents (NSAIDs), particularly chronic use 

●Antidepressants, including tricyclic antidepressants, selective serotonin reuptake inhibitors, and monoamine oxidase inhibitors

•Corticosteroids, including both glucocorticoids and mineralocorticoids

•Decongestants, such as phenylephrine and pseudoephedrine

•Some weight-loss medications

•Sodium-containing antacids

•Erythropoietin

•Cyclosporine or tacrolimus

•Stimulants, including methylphenidate and amphetamines

•Atypical antipsychotics, including clozapine and olanzapine

•Angiogenesis inhibitors, such as bevacizumab

•Tyrosine kinase inhibitors, such as sunitinib and sorafenib

●Illicit drug use – Drugs such as methamphetamines and cocaine can raise blood pressure.

●Primary kidney disease – Both acute and chronic kidney disease can lead to hypertension. 

●Primary aldosteronism – The presence of primary mineralocorticoid excess, primarily aldosterone, should be suspected in any patient with the triad of hypertension, unexplained hypokalemia, and metabolic alkalosis. However, up to 50 to 70 percent of patients will have a normal plasma potassium concentration. Other disorders or ingestions can mimic primary aldosteronism (apparent mineralocorticoid excess syndromes), including chronic licorice intake.

●Renovascular hypertension – Renovascular hypertension is often due to fibromuscular dysplasia in younger patients and to atherosclerosis in older patients. 

●Obstructive sleep apnea – Disordered breathing during sleep appears to be an independent risk factor for systemic hypertension.

●Pheochromocytoma – Pheochromocytoma is a rare cause of secondary hypertension. Approximately one-half of patients with pheochromocytoma have paroxysmal hypertension; most of the rest have what appears to be primary hypertension.

●Cushing's syndrome – Cushing's syndrome is a rare cause of secondary hypertension, but hypertension is a major cause of morbidity and death in patients with Cushing's syndrome.

●Other endocrine disorders – Hypothyroidism, hyperthyroidism, and hyperparathyroidism may also induce hypertension.

●Coarctation of the aorta – Coarctation of the aorta is one of the major causes of secondary hypertension in young children, but it may also be diagnosed in adulthood.

Symptoms:

severe headaches

chest pain

dizziness

difficulty breathing

nausea

vomiting

blurred vision or other vision changes

anxiety

confusion

buzzing in the ears

nosebleeds

abnormal heart rhythm

COMPLICATIONS OF HYPERTENSION:

●Left ventricular hypertrophy (LVH)

●Heart failure, both reduced ejection fraction (systolic) and preserved ejection fraction (diastolic) 

●Ischemic stroke

●Intracerebral hemorrhage

●Ischemic heart disease, including myocardial infarction and coronary interventions

●Chronic kidney disease and end-stage kidney disease 

DIAGNOSIS OF HYPERTENSION:

Classification Systolic and diastolic readings

●Normal systolic: less than 120 mm Hg

diastolic: less than 80 mm Hg

●Elevated systolic: 120–129 mm Hg

diastolic: less than 80 mm Hg

●High blood pressure systolic: 130 mm Hg or higher

diastolic: 80 mm Hg or higher

Laboratory testing:

●Electrolytes (including calcium) and serum creatinine (to calculate the estimated glomerular filtration rate)

●Fasting glucose

●Urinalysis

●Complete blood count

●Thyroid-stimulating hormone

●Lipid profile

●Electrocardiogram

●Calculate 10-year atherosclerotic cardiovascular disease risk

TREATMENT:

Nonpharmacologic therapy:

●Dietary salt restriction – In well-controlled randomized trials, the overall impact of moderate sodium reduction is a fall in blood pressure in hypertensive and normotensive individuals of 4.8/2.5 and 1.9/1.1 mmHg, respectively. The effects of sodium restriction on blood pressure, cardiovascular disease, and mortality as well as specific recommendations for sodium intake, are discussed in detail elsewhere.

●Potassium supplementation, preferably by dietary modification, unless contraindicated by the presence of chronic kidney disease or use of drugs that reduce potassium excretion.

●Weight loss – Weight loss in overweight or obese individuals can lead to a significant fall in blood pressure independent of exercise. The decline in blood pressure induced by weight loss can also occur in the absence of dietary sodium restriction [53], but even modest sodium restriction may produce an additive antihypertensive effect. The weight loss-induced decline in blood pressure generally ranges from 0.5 to 2 mmHg for every 1 kg of weight lost.

●DASH diet – The Dietary Approaches to Stop Hypertension (DASH) dietary pattern is high in vegetables, fruits, low-fat dairy products, whole grains, poultry, fish, and nuts and low in sweets, sugar-sweetened beverages, and red meats. The DASH dietary pattern is consequently rich in potassium, magnesium, calcium, protein, and fiber but low in saturated fat, total fat, and cholesterol. A trial in which all food was supplied to normotensive or mildly hypertensive adults found that the DASH dietary pattern reduced blood pressure by 6/4 mmHg compared with a typical American-style diet that contained the same amount of sodium and the same number of calories. Combining the DASH dietary pattern with modest sodium restriction produced an additive antihypertensive effect. These trials and a review of diet in the treatment of hypertension are discussed in detail elsewhere.

●Exercise – Aerobic, dynamic resistance and isometric resistance exercise can decrease systolic and diastolic pressure by, on average, 4 to 6 mmHg and 3 mmHg, respectively, independent of weight loss. Most studies demonstrating a reduction in blood pressure have employed at least three to four sessions per week of moderate-intensity aerobic exercise lasting approximately 40 minutes for a period of 12 weeks. 

●Limited alcohol intake – Women who consume two or more alcoholic beverages per day and men who have three or more drinks per day have a significantly increased incidence of hypertension compared with nondrinkers. Adult men and women with hypertension should consume, respectively, no more than two and one alcoholic drinks daily.

Pharmacologic therapy:

●Thiazide-like or thiazide-type diuretics

●Long-acting calcium channel blockers (most often a dihydropyridine such as amlodipine)

●Angiotensin-converting enzyme (ACE) inhibitors

●Angiotensin II receptor blockers (ARBs)

Combination therapy:

Single-agent therapy will not adequately control blood pressure in most patients whose baseline systolic blood pressure is 15 mmHg or more above their goal. Combination therapy with drugs from different classes has a substantially greater blood pressure-lowering effect than doubling the dose of a single agent, often with a reduction in side effects seen with a higher dose of monotherapy. When more than one agent is needed to control the blood pressure, we recommend therapy with a long-acting ACE inhibitor or ARB in concert with a long-acting dihydropyridine calcium channel blocker. Combination of an ACE inhibitor or ARB with a thiazide diuretic can also be used but may be less beneficial when hydrochlorothiazide is used. ACE inhibitors and ARBs should not be used together. 

Prevention:

Do:

•Eat more vegetables and fruits.

•Sit less.

•Be more physically active, which can include walking, running, swimming, dancing or activities that build strength, like lifting weights.

•Get at least 150 minutes per week of moderate-intensity aerobic activity or 75 minutes per week of vigorous aerobic activity.

•Do strength building exercises 2 or more days each week.

•Lose weight if you’re overweight or obese.

•Take medicines as prescribed by your health care professional.

•Keep appointments with your health care professional.

Don’t:

•Eat too much salty food (try to stay under 2 grams per day)

•Eat foods high in saturated or trans fats

•Smoke or use tobacco

•Drink too much alcohol (1 drink daily max for women, 2 for men)

•Miss or share medication.