according to some studies, prehypertension can increase the risk for heart attacks, strokes, congestive heart failure, and kidney failure. one study found that a prehypertensive person is more than three times more likely to have a heart attack and 1.7 times more likely to have heart disease than a person with normal blood pressure. a meta-analysis concluded that prehypertension increases the risk of stroke, and that even low-range prehypertension significantly increases stroke risk.