See below. Anyone can develop hypertension. It becomes more common as we get older and there are certain risk factors like obesity that make it more likely. Most forms of hypertension are called essential hypertension, meaning the exact cause of the condition is unknown. For some people with hypertension, things like weight loss and exercise can help alleviate the need for medication.
Multiple factors. Family history that means genetic reason, overweight/obese, high sodium diet, sedative life style, etc.