Managing the patient at risk for a second stroke.

Cerebrovascular disease is a major cause of mortality world-wide, and the prevalence is expected to increase as a result of projected demographic trends. Aggressive antihypertensive therapy is one intervention that has proven highly effective in reducing the risk of stroke, with relatively small blood pressure reductions affording measurable benefit even in patients not conventionally considered hypertensive. Comparative clinical trials are revealing evidence of differential impacts of antihypertensive classes on the incidence of cerebrovascular disease that will probably be important for therapeutic choice in patients with risk factors for stroke. In particular, the role of the renin-angiotensin system in cerebrovascular disease has come under scrutiny as a result of evidence that angiotensin II receptor blockers (ARBs), but perhaps not angiotensin converting enzyme inhibitors, can reduce the risk of a first stroke to a greater degree than might be expected from their effects on blood pressure alone. Although preclinical evidence suggests that there are differential effects of the type 1 and type 2 receptor activation, the clinical relevance of this is not yet known. Furthermore, the effect on the incidence of stroke conferred by blood pressure control in the early morning hours - the time when the incidence of strokes peaks--has not been tested. Some evidence for the beneficial effect of an ARB on secondary stroke prevention comes from the MOrbidity and mortality after Stroke --Eprosartan compared with nitrendipine in Secondary prevention study (MOSES), which showed that the ARB protected against cerebro- and cardiovascular events in hypertensive patients with a previous stroke over and above the protection offered by blood pressure control. These hypotheses are among those being examined in two current large-scale trials: the Prevention Regimen For Effectively avoiding Second Strokes (PRoFESS), and The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) Trial Programme.