Antihypertensive therapy in the prevention of stroke - What, when and for whom?

It is clear that antihypertensive regimens based on a low dose thiazide diu retic are effective for the primary prevention of stroke, particularly in o lder patients. In patients with diabetes mellitus who are at a higher risk of stroke, low dose thiazide diuretics and ACE inhibitors are of benefit. I n those with isolated systolic hypertension, long-acting dihydropyridine ca lcium antagonists, in addition to low dose thiazide diuretics, have also be en shown to significantly reduce stroke risk. However, to attain sufficient lowering of blood pressure (BP) to most effectively reduce the risk of str oke (i.e. to levels of 140-150/80-85mm Hg or lower and perhaps to <140/<80m m Hg in patients with diabetes mellitus) combination therapy will be requir ed. Immediately following stroke BP tends to fall spontaneously and therapy is probably not required in the great majority of patients during the firs t few days poststroke. If treatment is required shortly after this period, agents with a slow and gentle onset of action appear to be preferable; some preliminary data suggest that ACE inhibitors, despite lowering systemic BP , have no significant effect on cerebral blood flow. However, there is Litt le clinical outcome data to clearly define the role of antihypertensive tre atment in the early poststroke period. Whether existing antihypertensive th erapy should be continued following stroke is also unclear, but such decisi ons may be influenced by factors such as the actual BP level, other indicat ions for treatment (e.g. angina pectoris or cardiac failure) or the presenc e of dysphagia. There is more evidence to suggest that, some weeks to month s following stroke (particularly a minor stroke), lower rather than higher BP is favourable, and better control of high BP with therapy reduces stroke recurrence.