The Pharmaco-chronological Effects of Irbesartan on Day-night Rhythm of Blood Pressure in Hypertensive Patients

Objective To investigate the pharmaco-chronological effects of irbesartan on day-night rhythm of blood pressure in non-dipper hypertensive patients.Methods Eighty-three non-dipper hypertensive patients were divided into two classes:morning dose(n=41) and evening dose program(n=42).All patients were treated with irbesartan(150～300mg/d) for 24 weeks.Results Both programs decreased office SBP with no differences between them.ABPM showed that both programs effectively decreased night SBP,while evening program reduced night SBP more pronouncedly.Although The target day-time SBP(135 mmHg) was of no differences between the two programs(36.5% vs 33.3%,P0.05),the target night-time SBP(125 mmHg) was achieved by evening program in52.4% patients which was greatly higher than that by morning program(29.2%,P0.01).Circadian rhythm transformed from non-dipper to dipper was found in 19.5% in morning program versus 52.4% in the evening program(P0.01).Conclusion The evening programs of irbesartan administration were effective in decreasing night BP and improving day-night rhythm of blood pressure.