Hypertension is an average or sustained systolic blood pressure over 140 mm Hg and/or a diastolic blood pressure over 90 mm Hg. Hypertension has an overall incidence of 20%, with onset usually occurring after age 20. The prevalence rises with age to over 50% over age 65. Ninety-five to 99% of hypertensive individuals have essential hypertension. Persons with hypertension are three to four times more likely to experience a major cardiovascular event (e.g., myocardial infarction, cerebrovascular accident, congestive heart failure).

Categories of hypertension (measured in mm Hg):

Stage 1 (mild)Systolic BP 140 to 159Diastolic BP 90 to 99

Stage 2 (moderate)Systolic BP 160 to 179 Diastolic BP 100 to 109

Stage 3 (severe)Systolic BP 180 to 209 Diastolic BP 110 to 119

Stage 4 (very severe)Systolic BP ^>210Diastolic BP ^>120

• Essential, or primary, hypertension has no identifiable cause.
• Secondary hypertension may be caused by renal, endocrine, and vascular conditions; coarctation of the aorta, certain neurological conditions, acute stress, and chronic heavy alcohol use. Use of oral contraceptives, decongestants, and antidepressants may also cause secondary hypertension.

Hypertension is more common in African-Americans at all ages and in persons from lower socioeconomic groups. Individual risk factors include the following.

• Family history
• Alcohol use
• High sodium intake
• Stress
• Sedentary lifestyle
• Obesity
• High sugar intake

Essential hypertension has no symptoms except in extreme cases or after cardiovascular complications result. Extremely high blood pressures may cause headaches.

Severe hypertension or hypertensive crisis (usually secondary hypertension) with end-organ damage may produce headache, nausea and vomiting, seizure, retinopathy, and other symptoms.

Tests to determine possible causes are performed only if a secondary cause is suspected.

Hypertension is diagnosed through blood pressure measurements. Guidelines include controlling the patient's posture when taking the blood pressure; restricting the use of caffeine, nicotine, and other stimulants before taking the blood pressure; using the appropriate size cuff; and taking at least three readings at least one week apart.

Diagnostic procedures focus on screening for causes and risk factors, assessing potential end-organ damage from sustained hypertension.

The history should include past blood pressure levels, family history, past conditions, diet (especially salt and cholesterol intake), exercise, current medications, alcohol and tobacco use, and stressors.

Physical examination should include the following.

• Blood pressure taken on right and left arms, both sitting and standing
• Heart rate and rhythm
• Peripheral and femoral pulses
• Fundoscopy
• Weight
• Complete family and patient history

• Complete blood count
• Calcium level
• Creatinine level
• Potassium level
• Sodium level
• Fasting glucose and insulin levels
• Cholesterol levels
• Uric acid level
• Urinalysis

There are pathological findings only if organ damage has begun to occur from sustained hypertension; see "Complications."

Only required for differential diagnosis or if end-organ damage is suspected.

• Chest X ray
• Ultrasonography
• IVP and renal arteriogram
• Provocative renal nuclear scan
• Digital subtraction arteriography
• Angiogram

Only required for differential diagnosis or if end-organ damage is suspected.

• Plasma catecholamines
• Urinary metanephrines
• Plasma renin
• Electroencephalography

The goal of treatment is to lower the risk of future cardiovascular damage by lowering the blood pressure to below 140 mm Hg (systolic) and 90 mm Hg (diastolic). In stage 3 or 4 hypertension, significant partial reduction is acceptable.

Nonpharmacological therapies may be used with or without drug therapy. Nondrug therapies are generally used with stage 1 hypertension and should be evaluated over the course of 6 to 12 months. Drug treatment is usually required for more severe hypertension and usually provides control within one to three months.

Lifestyle modifications that lower blood pressure include the following.

• Weight reduction
• Sodium restriction
• Discontinuation or restriction of alcohol
• Discontinuation of caffeine
• Exercise
• Patient education about the importance of lowering blood pressure
• Biofeedback and relaxation techniques

Each case should be considered individually, yet drug therapy is recommended for patients with sustained systolic pressure over 160 mm Hg or diastolic pressure over 100 mm Hg. Traditionally, therapy with a diuretic or beta-blocker is tried first. The dosage may be modified or an additional drug from another class may be added. Ten percent of patients may require three drugs.

• Diuretics—e.g., hydrochlorothiazide (Hydrodiuril; 12.5 to 50 mg/day); side effects include decreased level of potassium and increased cholesterol and glucose levels; contraindicated in patients with gout and diabetes
• Potassium-sparing agents—spironolactone (Aldactazide; 25 to 100 mg/day); side effects include hyperkalemia and gynecomastia

Adrenergic inhibitors include the following.

• Alpha-blockers—doxazosin (Cardura; 1 to 20 mg/day); side effects include postural hypotension and lassitude
• Beta-blockers—acebutolol (Sectral; 200 to 800 mg/day); side effects include congestive heart failure, bronchospasm, masking of hypoglycemia induced by insulin, depression, insomnia, fatigue; contraindicated relatively in heart failure, airway disease, heart block, diabetes, and peripheral vascular disease
• Alpha/beta blockers—labetalol (Normodyne; 200 to 1,200 mg/day in two doses); side effects include postural hypotension and beta-blocker side effects
• Centrally acting sympatholytics—methyldopa (Aldomet; 500 to 3,000 mg/day in two doses); side effects include hepatic disorders, sedation, dry mouth
• Peripherally acting sympatholytics—reserpine (Serpasil; 0.05 to 0.25 mg/day); side effects include sedation and depression
• Calcium-channel blockers—verapamil (Isoptin; 90 to 480 mg/day); side effects include constipation, nausea, headache, conduction defects; use with caution in heart failure or block
• Dihydropyridines—amlodipine (Norvase; 2.5 to 10 mg/day); side effects include flushing, headache, ankle edema
• Direct vasodilators—hydralazine (Apresoline; 50 to 400 mg/day in two doses); side effects include headache, tachycardia, lupus syndrome
• Angiotensin-converting enzyme (ACE) inhibitors—benazepril (Lotensin; 5 to 40 mg/day); side effects include cough, rash, loss of taste; use with caution in renovascular disease

Mind-body techniques (such as biofeedback, yoga, meditation, and stress management), nutritional and herbal support may be effective in improving hypertension and concurrent pathologies.

• Avoid caffeine and decrease intake of refined foods, sugar, and saturated fats (meats and dairy products). Some kinds of hypertension respond to a reduction of salt intake.
• Eliminate food allergens as these may exacerbate hypertension. Increase dietary fiber, vegetables and vegetable proteins, and essential fatty acids (cold-water fish, nuts, and seeds).
• EPA, flaxseed oil, or evening primrose oil (1,000 to 1,500 mg one to two times/day) lowers cholesterol and mildly reduces hypertension.
• Magnesium (200 mg bid to tid) induces mild vasodilation to decrease blood pressure.
• Zinc (30 mg/day) may help reduce blood pressure that is associated with high levels of cadmium (usually secondary to cigarette smoking).
• Coenzyme Q10 (50 to 100 mg one to two times/day) is protective to the cardiovascular system.
• B complex (50 to 100 mg/day) with additional folic acid (800 mcg/day), B12 (1,200 mcg/day), and betaine (1,000 mg/day) may increase resistance of stress and lower blood pressure that is secondary to homocysteinemia.
• Vitamin E (400 IU/day) reduces platelet aggregation.
• Some patients are sensitive to grains. A trial of limiting grain-based foods in the diet should be implemented to assess the effect on blood pressure.

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, it is important to ascertain a diagnosis before pursuing treatment. Herbs may be used as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, teas should be made with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink two to four cups/day. Tinctures may be used singly or in combination as noted.

Hawthorn (Crataegus monogyna), linden flowers (Tilia cordata), passionflower (Passiflora incarnata), valerian (Valeriana officinalis), and cramp bark (Viburnum opulus) may be safely used long-term. These herbs relax and strengthen the cardiovascular system while moderately reducing blood pressure. Combine equal parts in a tincture, 20 to 30 drops tid or qid. Hawthorn may be taken as a dried extract, 250 mg tid.

Dandelion leaf (Taraxacum officinale) has a diuretic effect and spares potassium. Drink three to four cups/day.

The following herbs have a stronger hypotensive effect and may have toxic side effects. These herbs must be used under the supervision of a qualified practitioner. Lily of the valley (Convallaria majalis), night-blooming cereus (Selenicereus grandiflorus), mistletoe (Viscum album), motherwort (Leonurus cardiaca), and Indian tobacco (Lobelia inflata). Combine 3 to 4 of these herbs with equal parts of cramp bark and valerian and take 30 to 60 drops tid.

An experienced homeopath should assess individual constitutional types and severity of disease to select the correct remedy and potency.

Acupuncture may be helpful in reducing blood pressure, alleviating stress, and addressing concurrent pathologies.

Therapeutic massage may be effective in reducing the effects of stress and inducing relaxation and lowered blood pressure.

Since patient compliance is poor with antihypertensive medications, with up to 20% of patients discontinuing the drug, patient education and follow-up are critical. Even after blood pressure is stabilized, changes in the medical regimen will be required for some patients for months and years. Schedule follow-up visits every three to six months.

Individuals with high normal or stage 1 hypertension may be able to prevent hypertension with a low-sodium diet, exercise, relaxation techniques, weight reduction, alcohol avoidance, and smoking cessation.

The complications of untreated hypertension include the following.

• Stroke
• Aortic aneurysm
• Myocardial infarction
• Congestive heart failure
• Cardiac enlargement
• Left ventricular hypertrophy
• Renal insufficiency
• Cerebral thrombosis or embolization

Controlled hypertension results in greatly diminished risks of complications and a generally good prognosis.

Mild elevation of blood pressure can be normal in pregnancy, however, pregnancy-induced hypertension can progress rapidly to life-threatening sequelae. Blood pressure should be monitored frequently during pregnancy. Hawthorn, linden flowers, passionflower, valerian, and cramp bark may be used safely in pregnancy after the first trimester. Further intervention must be under the supervision of a physician.

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