Annals of Internal Medicine
EDITORIAL
The Benefits of Detecting and Treating Mild Hypertension: What We Know, and What We Need to Learn
T
his issue includes 2 systematic reviews dealing with the diagnosis and management of hypertension. In the first, Sundstro¨m and colleagues assess the evidence on the effects of blood pressure reduction on cardiovascular outcomes in patients with stage 1 hypertension (1). In the second, Piper and associates evaluate methods used to identify persons with elevated blood pressure (2). Sundstro¨m and colleagues combined data from a previous systematic review of 3 trials (3) with patientlevel data from participants with stage 1 hypertension in the BPLTTC (Blood Pressure Lowering Treatment Trialists' Collaboration) database (4). The earlier review reported no significant reduction in cardiovascular events, death, or stroke with treatment of stage 1 hypertension but acknowledged that data were limited. Sundstrom and colleagues' analysis included patients at a mean age of 63.5 years who had baseline blood pressures of 140 to 160/90 to 99 mm Hg, had no previous clinical cardiovascular disease or renal failure, and were followed for at least 1 year. In contrast to the earlier review, most of the BPLTTC participants (96%) were diabetic, and 61% were receiving antihypertensive medications at baseline. The addition of these patients increased the number of participants from 8912 to 15 266, the number of cardiovascular events from 165 to 661, the number of strokes from 30 to 154, and the number of deaths from 167 to 665 compared with the previous review. Both placebo and less intensive treatment were compared with intensive treatment. The more aggressive drug treatment resulted in a modest average blood pressure reduction of 3.6/2.4 mm Hg and was associated with significant reductions in stroke (28%), cardiovascular deaths (25%), and total deaths (22%), but no difference in total cardiovascular outcomes. The findings did not differ between BPLTTC and non-BPLTTC studies or by diabetes status or age. The results are consistent with those of prior analyses in hypertension clinical outcome trials that showed that blood pressure reductions, even within this lower range, are associated with favorable cardiovascular outcomes (4 –7). Sundstro¨m and colleagues' work is timely in light of a recent guideline that recommended relaxing blood pressure goals in patients older than 60 years (the population at highest risk) (8, 9). In addition, although all other U.S. and international guidelines continue to recommend antihypertensive drug treatment to achieve blood pressure targets less than 140/90 mm Hg at least up to age 80 years, the National Committee for Quality Assurance has relaxed its target blood pressure quality metric from less than 140/90 mm Hg to less than 150/90 mm Hg in patients older than 60 years.
Of note, the strength of evidence in Sundstro¨m and colleagues' review is not equivalent to that in a prospective trial comparing treatment versus no treatment of stage 1 hypertension. None of the included studies specifically enrolled patients with stage 1 hypertension, and because washout of antihypertensive agents was not required in all studies, some participants may have been enrolled with higher blood pressures. In addition, the primary objective of several of the trials in the review was to compare the effect of specific drug regimens rather than the effects of different blood pressures on clinical outcomes, and blood pressure targets in these trials were not uniformly defined. A trial specifically designed to assess the benefit of initiating treatment in this population was considered by the National Heart, Lung, and Blood Institute, but preference was given to trials assessing the effect of the even lower blood pressure targets (systolic blood pressure
EDITORIAL
The Benefits of Detecting and Treating Mild Hypertension: What We Know, and What We Need to Learn
T
his issue includes 2 systematic reviews dealing with the diagnosis and management of hypertension. In the first, Sundstro¨m and colleagues assess the evidence on the effects of blood pressure reduction on cardiovascular outcomes in patients with stage 1 hypertension (1). In the second, Piper and associates evaluate methods used to identify persons with elevated blood pressure (2). Sundstro¨m and colleagues combined data from a previous systematic review of 3 trials (3) with patientlevel data from participants with stage 1 hypertension in the BPLTTC (Blood Pressure Lowering Treatment Trialists' Collaboration) database (4). The earlier review reported no significant reduction in cardiovascular events, death, or stroke with treatment of stage 1 hypertension but acknowledged that data were limited. Sundstrom and colleagues' analysis included patients at a mean age of 63.5 years who had baseline blood pressures of 140 to 160/90 to 99 mm Hg, had no previous clinical cardiovascular disease or renal failure, and were followed for at least 1 year. In contrast to the earlier review, most of the BPLTTC participants (96%) were diabetic, and 61% were receiving antihypertensive medications at baseline. The addition of these patients increased the number of participants from 8912 to 15 266, the number of cardiovascular events from 165 to 661, the number of strokes from 30 to 154, and the number of deaths from 167 to 665 compared with the previous review. Both placebo and less intensive treatment were compared with intensive treatment. The more aggressive drug treatment resulted in a modest average blood pressure reduction of 3.6/2.4 mm Hg and was associated with significant reductions in stroke (28%), cardiovascular deaths (25%), and total deaths (22%), but no difference in total cardiovascular outcomes. The findings did not differ between BPLTTC and non-BPLTTC studies or by diabetes status or age. The results are consistent with those of prior analyses in hypertension clinical outcome trials that showed that blood pressure reductions, even within this lower range, are associated with favorable cardiovascular outcomes (4 –7). Sundstro¨m and colleagues' work is timely in light of a recent guideline that recommended relaxing blood pressure goals in patients older than 60 years (the population at highest risk) (8, 9). In addition, although all other U.S. and international guidelines continue to recommend antihypertensive drug treatment to achieve blood pressure targets less than 140/90 mm Hg at least up to age 80 years, the National Committee for Quality Assurance has relaxed its target blood pressure quality metric from less than 140/90 mm Hg to less than 150/90 mm Hg in patients older than 60 years.
Of note, the strength of evidence in Sundstro¨m and colleagues' review is not equivalent to that in a prospective trial comparing treatment versus no treatment of stage 1 hypertension. None of the included studies specifically enrolled patients with stage 1 hypertension, and because washout of antihypertensive agents was not required in all studies, some participants may have been enrolled with higher blood pressures. In addition, the primary objective of several of the trials in the review was to compare the effect of specific drug regimens rather than the effects of different blood pressures on clinical outcomes, and blood pressure targets in these trials were not uniformly defined. A trial specifically designed to assess the benefit of initiating treatment in this population was considered by the National Heart, Lung, and Blood Institute, but preference was given to trials assessing the effect of the even lower blood pressure targets (systolic blood pressure
