The notion that hypertension is caused by anxiety is not particularly true. Anxiety may temporarily raise blood pressure due to response from adrenalin surge.

An example is white coat hypertension, which is temporary elevation in blood pressure due to the presence of medical personnel. Adrenalin is a hormone that helps somebody to respond to emergency or frightening situation.

As this is usually not a sustained condition, the response does not last for too long. It may last as long as the frightening situation persists, after which it goes back to normal. 

Hypertension is a disease that results from several risk factors. Significant among these risk factors are: 

1. Genetic factors – family history of hypertension, especially first degree relations such as father, mother, sisters and brothers; 
2. Diseases affecting other organs of the body such as the kidneys; 
3. Normal but special conditions like pregnancy;
4. Obesity – excess weight gain;
5. Unhealthy lifestyle such as sedentary lifestyle, eating junk foods (with excess salt, sugar and cholesterol etc).

These are not necessarily causes but risk factors because their presence does not necessarily lead to the presence of the disease. The presence of any of the factors only enhances the possibility of having the disease.