The results of a study of heart disease patients, reported in the Journal of the American Medical Association (November 10, 2004), found that "normal" blood pressure may not be low enough. The researchers found that by lowering the pressure well below the target numbers recommended by national guidelines the patients had fewer heart attacks, cardiac arrests, strokes, and deaths. National guidelines for most individuals say that systolic pressure should be lower than 140 mm Hg and diastolic pressure should be lower than 90 mm Hg. At the study's onset, the participants averaged 129/78 mm Hg.
The 2-year international study included 1991 patients. The group all had normal blood pressure, but was at high risk for adverse events. The study found that, for every 16 heart disease patients with normal blood pressure given drugs to lower it, 1 adverse event could be prevented. The researchers along with other experts agreed that more research was needed before modifying the guidelines.