I have gotten my share of random strangers coming up to me asking why I'm on oxygen. Many of them are older, some are also wearing oxygen, others are children. When I am asked why I'm on oxygen, I tell them I have pulmonary hypertension. I'd say about 99% of the people say, "Oh, I have high blood pressure, too!"
Well, that may be true, BUT, pulmonary hypertension has nothing to do with the high blood pressure everyone is familiar with! It is the OTHER hypertension. PH is high blood pressure in the lungs. If it is left untreated, it will eventually cause right-sided heart failure.
Oh, and by the way, my regular blood pressure is just fine, thank you!