What is hypertension and types of hypertension

Hypertension :

                    Hypertension is a clinical condition characterized by persistence rise of blood pressure above the normal range in respect of age and sex. Hypertension occurs when diastolic pressure is greater than 90 mm of Hg and systolic pressure is above 140 mm of Hg.

Hypertension is of 2 types :

1.      Primary or essential hypertension
2.    Secondary hypertension

Primary / Essential Hypertension :

      When arterial blood pressure persistently exceeds 150/90 or 160/100 mm of Hg. Its cause is unknown.

Secondary Hypertension:

                  It is due to other disease, as renal diseases, phaeochromocytoma by excess secration of glucocorticoids by coarctation of aorta.