Partial versus complete control of blood pressure in the prevention of hypertensive complications.

The data from the Veterans Administration Cooperative Study on Antihypertensive Agents Prevention of Morbidity Trial were reviewed from the point of view of the importance of normalizing the blood pressure in preventing cardiovascular complications. The treated group of patients was subdivided into three subgroups on the basis of the diastolic blood pressures recorded at the fourth month after randomization as follows: subgroup A, the poorly controlled patients whose diastolic blood pressures were 90 mm Hg or higher, an intermediate subgroup B with diatolic levels of 81 to 89 mm Hg, and subgroup C, the best controlled patients, all of whom exhibited diastolic blood pressures of 80 mm Hg or less. While the incidence of morbid events was slightly higher in subgroup A than in the other subgroups, the differences were not statistically significant. On the other hand, the incidence of morbid events in subgroup A was significantly lower (P less than 0.05) than in the untreated control patients (14.9% in subgroup A vs. 28.9% in the control group). While normalization of blood pressure is a desirable goal of treatment, even partial reduction appears to exert significant therapeutic benefit.