Objective: To assess the role of treated diastolic blood pressure (DBP) lev
el in stroke, coronary heart disease (CHD), and cardiovascular disease (CVD
) in patients with isolated systolic hypertension (ISH).
Design: An analysis of the 4736 participants in the Systolic Hypertension i
n the Elderly Program (SHEP) was undertaken. The SHEP was a randomized mult
icenter double-blind outpatient clinical trial of the impact of treating IS
H in men and women aged 60 years and older.
Main Outcome Measures: Cox proportional hazards regression analysis, with D
BP and systolic blood pressure (SBP) as time-dependent covariables.
Results: After adjustment for the baseline risk factors of race (black vs o
ther), sex, use of antihypertensive medication before the study, a composit
e variable (diabetes, previous heart attack, or stroke), age, and smoking h
istory (ever vs never) and adjustment for the SEP as a time-dependent varia
ble, we found, for the active treatment group only, that a decrease of 5 mm
Hg in DBP increased the risk for stroke (relative risk, [RR], 1.14; 95% co
nfidence interval [CI], 1.05-1.22),for CHD (RR, 1.08; 95% CI, 1.00-1.16), a
nd for CVD (RR, 1.11; 95% CI, 1.05-1.16).
Conclusions: Some patients with ISH may be treated to a level that uncovers
subclinical disease, and some may be overtreated. Further studies need to
determine whether excessively low DBP can be prevented by more careful titr
ation of antihypertensive therapy while maintaining SEP control. It is reas
suring that patients receiving treatment for ISH never perform worse than p
atients receiving placebo in terms of CVD events.