I was diagnosed with HBP at the age of 25 which led to an investigation into my family history, because I have always been a relatively healthy and active person. It turned out that my father, grandfather and most of my aunts, uncles, and cousins were being treated for HBP. My father was diagnosed at 30 after he had a mini-stroke and one of my uncles was diagnosed before he turned 21, so I know its hereditary.
I've done some cursory research and found that HBP can be caused by a heart valve problem, hyperthyroidism (I don't have), or arterial stiffness. Could it also be biochemical, in that we produce a higher concentration of chemicals that cause our hearts to pump faster and harder than they should? Do we just have poor cardiovascular systems? Also, are there any tests that can pinpoint the root cause of HBP?
Note: My father also has atrial fibrillation.