Hypertension refers to systolic blood pressures greater than 140 mm Hg or diastolic blood pressures greater than 90 mm Hg. Hypertension is diagnosed by two or more elevated blood pressure readings on two or more office visits after an initial screening.
|Normal||< 120 mmHg||and < 80 mmHg|
|Prehypertension||120-139 mmHg||or 80-89 mmHg|
|Stage I Hypertension||140-159 mmHg||or 90-99 mmHg|
|Stage II Hypertension||greater than or equal to 160 mmHg||greater than or equal to 100 mmHg|
Hypertension can be primary or secondary. Primary hypertension constitutes 85-95% of cases.
Primary hypertension:The mechanism of primary hypertension is unclear and seems to be lifestyle related. Factors such as dietary sodium, obesity, stress and a sedentary lifestyle are responsible for hypertension in genetically predisposed individuals. In patients > 65, high sodium intake is more likely to precipitate hypertension.
Secondary hypertension: Causes include primary aldosteronism, renal parenchymal disease such as glomerulonephritis, polycystic renal disease, pheochromocytoma, Cushing syndrome, congenital adrenal hyperplasia, hyperthyroidism and coarctation of the aorta. Use of sympathomimetics, excessive alcohol, corticosteroids, or cocaine worsen blood pressure control.
Symptoms and signs
Hypertension is usually asymptomatic until complications develop in target organs. Uncomplicated hypertension usually causes dizziness, flushed facies, fatigue, headache or epistaxis. Severe, untreated hypertension can cause cardiovascular, neurological, renal and retinal symptoms. It is important to treat hypertension early, before it causes damage to the organs.
JNC 8 Hypertension treatment guidelines
The Joint National Committee (JNC 8) hypertension guidelines were published in the Journal of the American Medical Association in 2013. Compared with previous guidelines, the new guidelines emphasize higher blood pressure goals for systolic blood pressure and diastolic blood pressure and less use of several antihypertensive medications.
Goal blood pressures according to JNC 8:
|Patients 60 years or older who do not have diabetes or chronic kidney disease||<150/90 mmHg|
|Patients 18-59 years without major comorbidities||<140/90 mmHg|
|Patients 18-59 years with diabetes or chronic kidney disease||<140/90 mmHg|