24-hour ambulatory blood-pressure effects of valsartan & hydrochlorothiazide combinations compared with amlodipine in hypertensive patients at increased cardiovascular risk: A VAST sub-study

Background There is a lack of data on the effects of angiotensin-receptor blocker and diuretic combinations on ambulatory blood pressure (ABP) in hypertensive patients with additional cardiovascular risk factors. Methods In a randomized, double-blind trial, the effects on 24-h ABP of the combination valsartan 160 mg od and hydrochlorothiazide 25 or 12.5 mg during 24 weeks of therapy were compared with the effects of amlodipine 10 mg monotherapy (group A10) in 474 stage-II hypertensive patients with additional cardiovascular risk factors. After a two-week single-blind placebo run-in period, patients were randomized to receive valsartan 160 mg od or amlodipine 5 mg od. At week 4, HCTZ 12.5 mg (group V160/HCTZ12.5) and 25 mg (group V160/HCTZ25) were added to the valsartan groups and in the A10 patients the amlodipine dose was force-titrated to 10 mg od. Results All three treatments reduced 24-h BP as well as night-time and daytime BP levels from baseline. Twenty-four hour systolic blood pressure (SBP) was reduced by 15.9±1.0 mmHg (least-squares mean change±SE), 19.3±1.0 mmHg and 16.1±1.1 mmHg in the V160/HCTZ12.5, V160/HCTZ25 and A10 groups, respectively and 24-h diastolic blood pressure (DBP) was reduced by 9.3±0.6 mmHg, 11.4±0.6 mmHg and 9.6±0.7 mmHg in the three groups. The differences between the V160/HCTZ25 group and the A10 group were significant (p<0.05) for the changes in 24-h systolic BP as well as for changes in daytime systolic BP and night-time diastolic BP. Control rates defined as ABPM ≤130/80 mmHg were: 48.4%, 60.8% and 50.9% in the V160/HCTZ12.5, V160/25 and A10 groups, respectively. The differences in control rates between the V160/HCTZ25 group and the other two treatment groups were significant at p<0.05. Conclusions The fixed-dose combination of valsartan 160 mg+HCTZ 25 mg od is an attractive therapeutic option measured on the effects on 24-h ABPM, night-time and daytime BP reduction and control rates in hypertensive patients at additional cardiovascular risk.