High blood pressure is elevated blood pressure measured on two separate occasions. It is classified as primary or secondary. Primary hypertension is also termed essential hypertension. Secondary hypertension is due to other factors such as hormonal excess, kidney artery disease, etc.
Blood pressure is similar to pressure one encounters in water pipes.
The upper number is systolic, the lower number diastolic. As a blood vessel loses its elasticity – often with age – the systolic blood pressure increases.
There are also other reasons why a person may have elevated, or high, blood pressure – this is called secondary hypertension. Causes range from hormone disorders such as Cushing syndrome, to tumors such as pheochromocytoma where there is excessive secretion of adrenaline, to coarctation of the aorta where there is kinking of the main blood vessel, to disease afflicting the kidney.
Certain illegal drugs can also cause high blood pressure.
Primary, or essential, hypertension is the most common ailment. There are no known causes but factors such as sedentary lifestyle, smoking, sleep apnea and obesity are often associated with this disease.
