In general hypertension has no specific cause (idiopathic). Hypertension occurs in response to increased cardiac output or increased peripheral pressure. However there are several factors that influence the occurrence of hypertension :
- Genetic : response to stress or neurological disorders or transport Na excretion.
- Obesity : associated with high insulin levels resulting in increased blood pressure.
- Environmental Stress.
- Loss of tissue elasticity and atherosclerosis in the elderly as well as dilation of blood vessels.
Based on the etiology Hypertension is divided into two groups, namely :
a. Essential hypertension (Primary)
- The cause is unknown but many factors that influence such as genetics, environment, hyperactivity, sympathetic nervous system, renin angiotensin system, the effect of excretion of Na, obesity, smoking and stress.
- Could be due to renal parenchymal disease / renal vascular.
- The use of oral contraceptive pills. Endocrine disorders etc.
- Aortic wall elasticity decreases.
- Valvular heart to thicken and become stiff.
- The heart's ability to pump blood decreased 1 % every year after the age of 20 years decreases the heart's ability to pump blood causes decreased contraction and volume.
- Loss of elasticity of blood vessels.
- This happens due to the lack of effectiveness of the peripheral blood vessels for oxygenation. The increased peripheral vascular resistance.
Although primary hypertension is not known with certainty the cause, data research has found several factors that often lead to hypertension. These factors are as follows :
- Heredity.
The characteristics of individuals :
- Individual traits that affect the incidence of hypertension are :
- Age (if the TD increases with age).
- Gender (males higher than females).
- Race (blacks more than whites).
- Living habits.
Habits that often cause hypertension are :
- High salt consumption (in excess of 30 g)
- Overweight or overeating.
- Stressed Out.
- Smoking.
- Drinking alcohol.
- Take drugs (ephedrine, prednisone, epinephrine).
While the causes of secondary hypertension are :
- Kidney .
- Glomerulonephritis.
- Pyelonephritis.
- Acute tubular necrosis.
- Tumors.
- Vascular.
- Atherosclerosis.
- Hyperplasia.
- Thrombosis.
- Aneurysm.
- Cholesterol embolism.
- Vasculitis.
- Endocrine disorders.
- DM.
- Hyperthyroidism.
- Hypothyroidism.
- Nerves.
- Stroke.
- Encephalitis.
- GBS.
- Drugs.
- Oral contraceptives.
- Corticosteroids.