atment of High Blood Pressure (JNC VII) (cited in Sharma and Kortas, 2008), hypertension in individuals above 18 years of age is defined and classified as follows:
Currently, most of the research in the world pertaining to hypertension is based on this classification. The CDC has reported that 29% of adult population in the US suffer from hypertension and 28% from prehypertension (Ayala, Kuklina and Peralez, et al, 2009).
Hypertension may occur due to many causes. Basically, there are 2 types of hypertension- essential hypertension and secondary hypertension. Hypertension is considered as essential when a recognizable secondary cause is absent. This is the most common form of hypertension and is seen in 95% cases with established diagnosis of hypertension (Sharma and Kortas, 2008). Secondary hypertension occurs secondary to some pathology in various organ systems in the body like kidney disease, coarctation of aorta and hormone derangements. This form of hypertension attributes to only 5% of hypertension cases (Sharma and Kortas, 2008). Essential hypertension is one of the leading causes for cardiac, cerebrovascular and renal diseases. It is actually a silent risk factor.
Essential hypertension basically evolves from occasional hypotension. After a prolonged period of asymptomatology, persistent hypertension ensues which then gradually evolves into complicated hypertension. In complicated hypertension, target organ damage occurs. The main organs which are affected as a result of prolonged hypertension are heart, kidneys, aorta and small arteries, central nervous system and retina. Prehypertension usually develops between 10-30 years of age and then gradually evolves into early hypertension between 20-40 years of age. At this time, peripheral resistance is marked and the most highlighted feature. Also, the hypertension is mainly high-output hypertension. This type of hypertension mainly results from decrease in the peripheral vascular resistance and simultaneous ...Show more