Comparative Effects of Losartan versus Benazepril and Their Combination on Essential Hypertension

Objective To compare the efficacy and safety of losartan, benazepril and their combination in essential hypertensive patients. Methods All patients were selected from mild to moderate essential hypertension [sitting diastolic blood pressure(SiDBP)90～109 mmHg]. After 1 week washing out period and two weeks of placebo administration,the patients were divided into three groups: Losartan(50 mg/d) group;Benazepril(10 mg/d) group;losartan(50 mg/d)+Benazepril(10 mg/d) group. A total of 67 patients were enrolled in the study and only 63 patients completed 8 week trail (L group, 22 patients; B group, 20 patients; L+B group, 21 patients). At the end of placebo run in and 1,2,4,6,8 weeks after treatment, the result of clinic blood pressure, heart rate(HR) and adverse effects are recorded. Plasma renin activity(PRA), angiotensin(AngⅡ) and aldosterone(ALD) concentration were examined before and after the treatment. Results At the end of 8 weeks, SiSBP/SiDBP was decreased by 10 8±6.2/17.5±5.5 mmHg by losartan, 11.2±5.4/16.4±4.6 mmHg by benazepril and 26.4±5.7/32.1±11.0 mmHg by the combination therapy. The combination therapy group elicited a significantly greater reduction on blood pressure than losartan or benazepril monotherapy group ( P 0 001). No difference in the magnitude of BP reduction and response rate had been found between Losartan group and benazepril group ( P 0 05). Plasma ALD of three groups were reduced after treatment, especially in the combination group. Conclusions Losartan effectively lowered blood pressure, was generally well tolerated. Additive antihypertensive effects were obvious when Losartan and Benazepril were combined.