Objective： To investigate the effects and safety of Western medicine combined with Chinese medicine （CM） based on syndrome differentiation in the treatment of elderly polarized hypertension （PHPT）, or isolated systolic hypertension with low diastolic blood pressure （DBP）. Methods： A total of 125 elderly patients with PHPT were randomly assigned to two groups： 59 in the control group treated by Western medicine and 66 in the intervention group treated by Western medicine combined with CM treatment. Based on syndrome differentiation, the patients in the intervention group were further divided into subgroups of yang-qi deficiency and yin-qi deficiency. All subjects were treated with Western medicine of Amlodipine Besylate Tablets and Irbesartan Tablets （or Irbesartan and Hydrochlorothiazide Tablets）, to decrease their systolic blood pressure （SBP） slowly to 125-135 mm Hg in 2-6 weeks. In the intervention group, Shiyiwei Shenqi Capsule （十一味参芪） was given additionally to the subgroup of yang-qi deficiency at the dosage of 3-5 capsules, thrice a day, while Dengzhan Shengmai Capsule （灯盏生脉胶囊） was given additionally to the subgroup of yin-qi deficiency at the dosage of 2 capsules, 2-3 times per day. For all subjects, SBP, pulse pressure （PP）, and DBP were measured before treatment and at the terminal of a 6-week treatment. For subjects in the intervention group, left ventricular ejection fraction （LVEF） was also recorded. Results： After a 6-week treatment, the SBP in the two groups and the PP in the intervention group decreased significantly compared to those before treatment （P〈0.05）, while the PP in the control group showed no significant difference between prior and post-treatment （P〉0.05）. After treatment, the DBP in the control group decreased （P〉0.05）, while the DBP and LVEF in the intervention group showed an increase tendency although it had no statistical significance （P〉0.05）. When subjects in the intervention group were cla
