Hypertension
Hypertension A Definition
Any blood pressure levels equal to or greater than systolic blood pressure of 140 mm of Hg and diastolic blood pressures of 90 mm of Hg are termed as Hypertension. Different screening studies have shown that about 25% of world population is hypertensive. The above mentioned facts indicate gravity of situation about the Hypertension. This situation is even more pathetic than these figures when we consider the Rule of Halves. The half of world population is hypertensive and mostly undiagnosed for hypertension. The 25% population of world fall into diagnosed range.Types of Hypertension
There are following two types of hypertension usually based upon the causeEssential hypertension
Secondary hypertension
Essential hypertension
It is the hypertension with out any cause involved in the emergence of disease. It is idiopathic hypertension, about 95% of hypertension is idiopathic hypertension.Secondary hypertension
This is hypertension resulting after a cause. This is the remaining 5% of hypertension. The most prominent cause of secondary hypertension is renal failure or renal artery stenosis.Obesity as a cause of hypertension
Obesity is one of the most established cause of hypertension. Obesity is not only a risk factor for the hypertension but now after a lot of studies it has become one of the most established cause of increase in blood pressure. The most evident fact is the decrease in blood pressure with loss of weight.Increase in BMI increase in Blood pressure – A linear relationship
BMI a potential indicator of obesity is moist helpful tool to quantify the obesity as a cause of hypertension. As BMI increases the chance of developing hypertension also increases. The following graph can help to understanding of the situation.
Graph depicting linear increase in % of hypertensive subjects in a study both in men and women with increase in BMI
After the age of 18 one kg of weight gain results in the 5% increase of chance of developing hypertension. Weight gain in the adulthood is a major risk factor for hypertension itself. Chronic Obesity is not the only one associated with the development of hypertension but acute or sudden weight gain is even more potentiated for the hypertension.
Biological mechanism involved in Obesity induced hypertension
The following mechanisms are of importance which are involved in the development of hypertension after considerable weight gain.- Activation of sympathetic nervous system
- Activation of renin-angiotensin system
- Thickness of vessel wall due to smooth muscle defects.
- Sodium retention associated with obesity
