ALISKIREN ADMINISTRATION TIME AND AMBULATORY BLOOD PRESSURE: PP.24.470

Alteration of circadian variability of blood pressure (BP) associates with an increase of the cardiovascular risk in hypertensive patients. Blocking the renin-angiotensin system (RAS) at night may modify the diurnal/nocturnal ratio of BP without changing the antihypertensive efficacy. The objective of this study was to assess the efficacy of Aliskiren administered on a time-dependent basis in a cohort of patients with essential hypertension. 53 patients (28 men, aged 54.5 ± 9.2 years) with non-treated mild to moderate essential hypertension were included. After clinical and biological assessment, patients received Aliskiren 300 mg/day on a time-dependent basis for a 12-week period. Following PROBE design, patients receive Aliskiren on awakening or at bedtime. The effects on both ambulatory and circadian pattern of BP were comparatively analysed before and after treatment with Aliskiren with ABPM. Demographic and clinical features, along with office and ambulatory BP, were similar in both treatment arms with no significant differences. In patients taking 300 mg of Aliskiren on awakening, the ambulatory BP was lowered regarding baseline values with changes in 24h-SBP/DBP (−12.9/−8.6 mmHg), in diurnal-SBP/DBP (−13.4/−8.8 mmHg) and in nocturnal-SBP/DBP (−11.1/−8.4 mmHg); p < 0.001, with no changes in the diurnal/nocturnal ratio of BP. In patients taking 300 mg of Aliskiren at bedtime, the ambulatory BP was lowered with changes in 24h-SBP/DBP (−14.5/−9.8 mmHg), in diurnal-SBP/DBP (−13.9/−9.3 mmHg) and in nocturnal-SBP/DBP (−16.1/−11.5 mmHg) with a significant increase in the diurnal/nocturnal ratio of SBP (+2.9%) and DBP (+4.4%), p < 0.001. Patients taking Aliskiren at bedtime showed a higher decrease in the mean nocturnal ambulatory SBP and DBP and a more significant increase in the diurnal/nocturnal ratio of BP than patients taking Aliskiren on awakening. Administration of Aliskiren controls BP throughout 24 hours with only one daily dose. However, the administration of this first direct renin inhibitor on a bedtime basis is more effective than awakening administration. This must be taken into account especially in those patients with an altered circadian pattern of BP.