A blood pressure reading averaging 142/90 is high, regardless of how long someone has had it. In fact, what you're describing is called lifelong hypertension. Over time, a blood pressure that high can put you at risk for coronary artery disease, stroke, heart failure, and kidney failure. It's important to get that blood pressure down; the goal should be 120/80. Someone with this blood pressure reading needs to talk to her doctor about how best to manage it.