Factors Influencing the Systolic Blood Pressure Response to Drug Therapy

In the early stage of hypertension, diastolic blood pressure has greater prognostic importance, but in the elderly, systolic blood pressure is the most important marker of cardiovascular complications. Therefore, the need for more strict control of this component of blood pressure must be reconsidered. The benefit obtained in different studies in the elderly suggests that the treatment of isolated systolic hypertension is associated with a reduction in overall cardiovascular mortality of 22%, in coronary heart disease mortality of 26%, and in stroke mortality of 33%. However, a higher percentage of patients (73%) attain the diastolic goal of <90 mm Hg, while only 34% have systolic pressure reduced to <140 mm Hg. In a review of randomized trials comparing at least four different antihypertensive drugs, significant differences in systolic blood pressure reduction have not been demonstrated, except in black populations, in whom calcium channel blockers and diuretics seem to be more effective. In patients with isolated systolic hypertension, data are inconclusive, but calcium channel blockers and diuretics appear to lower blood pressure to a greater degree than do other antihypertensive drugs. Two main predictors of difficulty in controlling systolic blood pressure are the baseline blood pressure and the presence of diabetes. Other predictors are the duration of arterial hypertension, older age, the presence of target organ damage and associated clinical conditions (myocardial infarction, stroke, chronic renal failure), and an elevated serum uric acid level. It appears that the profile of patients with a poorer therapeutic response includes a greater severity of hypertension and/or the presence of cardiovascular disease.