Update on the management of hypertension to prevent stroke.

Hypertension is the leading modifiable risk factor for stroke, including first-ever and recurrent stroke. The association between blood pressure (BP) and stroke risk is continuous and may be documented as low as 115/75 mm Hg. Because of this continuum of risk, and because most strokes occur in individuals with mild hypertension or even normal BP values, we are now beginning to recognize "prehypertension" as a stage in which early recognition and intervention may confer benefit. In addition to increased risk for ischemic and hemorrhagic stroke, hypertension may be associated with increased risk of cognitive impairment. Reductions in BP are reliably associated with reduced stroke risk. Some evidence suggests that certain agents, including angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, may have protective effects beyond BP lowering. Overall, the degree of BP lowering is key, and therefore most classes of BP-lowering agents may be recommended at this point. Many patients with hypertension will require more than one BP-lowering agent to control BP. Lifestyle modification is appropriate at all levels of intervention. Further studies are needed to ascertain the mechanisms of benefit of different classes of antihypertensive agents in the reduction of stroke and cardiovascular disease risk.