A high systolic blood pressure predicts the risk of cardiovascular disease better than an increase in diastolic blood pressure do. Though this was observed more than three decades ago, still no attempt was made to translate this evidence into practice until in 1993, when isolated systolic hypertension was recognized as an important target for the control of blood pressure.
Although associated with more variability when measured, it is still easier to determine systolic blood pressure and it allows more appropriate risk stratification compared to diastolic blood pressure.
In a recent analysis of a heart study made, by only knowing the systolic blood pressure the stage of blood pressure in 99% of adults over age 60 are correctly classified whereas knowing the diastolic blood pressure allowed only 66% to be correctly classified. By definition, isolated systolic hypertension is a systolic blood pressure more than or equal to 140 mm Hg and a diastolic blood pressure less than 90 mm Hg and is the most common form of hypertension. Its prevalence increases with age, which occurs in two thirds of people who are 65 years of age and three quarters of those over 75 years old.
The benefits obtained from treating systolic blood pressure have been clearly documented. Trials made have shown significant reductions in stroke, coronary vascular disease, heart failure, and mortality rate when treating patients with isolated systolic hypertension (systolic blood pressure is more than 150 or 160 mm Hg and diastolic blood pressure is less than 90 mm Hg).
When systolic blood pressure was reduced by at least 20 mm Hg and to less than 160 mm Hg or less than 150 mm Hg, there’s a 35-40 reduction in stroke, a 50 reduction in heart failure, a 16% reduction in coronary events, and a 10-15% reduction in mortality rate occurred. The benefits of treating stage 1 isolated systolic hypertension have still not yet been shown in a clinical trial. Though none of the clinical trials achieved a systolic blood pressure below 140 mm Hg, consensus statements suggest that outcome should improve further if this goal is achieved.
