A Randomized, Double-Blind Clinical Trial to Determine the Efficacy of

Background：Carvedilol, an antihypertensive agent with β-blocking and vasodilating properties, has been demonstrated to be effective in reducing blood pressure. The purpose of this study is to compare the antihypertensive efficacy, safety and tolerability of carvedilol and atenolol in patients with stage 1 to 2 essential hypertension. Methods：In this double-blind, double-dummy, randomized, parallel study, the efficacy, safety and tolerability of once-daily carvedilol versus once-daily atenolol were evaluated in 58 patients for 8 weeks with stage 1-2 hypertension. If mean peak sitting diastolic blood pressure was equal to or greater than 90mmHg after a 4 week treatment period, the dosage for both study drugs were doubled until the end of study. Results：Data from 58 of 73 patients who completed the study were eligible for perprotocol analysis. At 4 weeks post treatment commencement, mean reductions in peak sitting diastolic blood pressure were 13.9mmHg(95 % confidence interval 17.1-11.4) with 25mg carvedilol and 13.6mmHg (95 % confidence interval 16.8-10.3) with 50mg atenolol. After the 8 week treatment period with dose titration, mean reductions in peak sitting diastolic blood pressure were 14.7mmHg(95