Don t underestimate risks associated with prehypertension

Classified as the silent killer, hypertension is the underlying cause of many adverse health outcomes, including heart attacks, strokes, and kidney disease. Though many people are aware of the dangers associated with high blood pressure, few may know that even a slightly raised blood pressure, known as prehypertension (systolic pressure of 120 to 139 mm Hg, or a diastolic pressure of 80 to 89 mm Hg), also puts people at an increased risk of stroke.

In a study published in the journal Neurology, researchers from the University of California at San Diego reviewed data on over 500,000 participants with follow-up periods as long as 32 years. They found that, for people under the age of 65, prehypertension was associated with a 68 percent increased risk of stroke, compared to those with normal readings. Interestingly, the elevated risk was not present among people over the age of 65. Further, the elevated risk was restricted to those whose blood pressure was in the high-normal range (130/85 to 139/89 mm Hg). In those subjects, the risk was almost 80 percent higher than it was in controls.

One of the study s authors, Dr. Bruce Ovbiagele, suggests that prehypertensive patients should not necessarily start taking blood pressure medication right away, but should instead consider modifying their lifestyles first by lowering their sodium intake and maintaining an ideal weight in order to lower their blood pressure.

Though ACSH's Dr. Gilbert Ross agrees that weight loss may help to decrease blood pressure readings, he is not so confident that dietary modifications will be very effective. Instead, I would advise prehypertensive patients to invest in an at-home blood pressure machine that they should use a few times a week. He adds, If losing weight doesn t help lower their blood pressure, then I would start these patients on anti-hypertensive medications, which have been proven to be quite safe and effective. And they should eliminate risk factors that contribute to preventable illnesses such as stroke; quitting smoking is one such.

As Dr. Ross points out, the study results seem to subtly suggest the possibility that the cut-off for high blood pressure may be lowered, so that the condition would be diagnosed at a reading closer to 130/85 mm Hg, instead of the current minimum of 140/90 mm Hg. I would just scrap the prehypertension category altogether and say that high blood pressure starts at 130/85 mm Hg, says Dr. Ross. And if a patient s blood pressure is higher than that, antihypertensive therapy should be strongly considered.