The case for low blood pressure targets

Abstract

The "totality" of hypertension clinical trial endpoint data has shown that the absolute benefit of pharmacological blood pressure (BP) lowering is directly related to the BP level and baseline cardiovascular risk, albeit with attenuation of the relative risk reduction per unit of BP lowering in patients with diabetes and chronic kidney disease. Absolute risk reductions with pharmacological treatment are greater with advancing age. Cardiovascular risk and mortality reductions attributable to pharmacological BP lowering have been demonstrated for progressively lower BP levels extending well below the conventional BP threshold (140/90 mm Hg) for hypertension. Hypertension endpoint trials have shifted from determining the relative clinical benefits of various antihypertensive drugs to exploring whether lower than conventional BP targets in persons with BP levels spanning the prehypertensive to much higher BP strata confer clinical benefit. The more recent of these trials were "relatively" agnostic to the drugs used for BP lowering although several trials provided, but did not mandate the use of, specific agents. Pharmacological treatment benefit has been demonstrated at pretreatment BP levels even lower than the intensive SPRINT BP target (<120 mm Hg) and a growing body of evidence suggests that substantial risk reduction can be achieved by maintaining a normal BP over time (rather than waiting for BP to exceed 140/90 mm Hg before treating). Thus there is a compelling rationale to lower the BP threshold not just for a therapeutic goal but also for the initiation of pharmacological intervention.