Major Finding: In study 2, the mean reduction in the central measure of systolic blood pressure was significantly greater in the aliskiren/amlodipine group, compared with the amlodipine-only group after 8 weeks of treatment (29.8 mm Hg and 24.2 mm Hg, respectively).
Data Source: A subset of patients totaling 775 from two safety and efficacy studies of aliskiren/hydrochlorothiazide.
Disclosures: Novartis Pharmaceuticals supported the study. Dr. Ferdinand had no financial conflicts to disclose, but one of the study coauthors is an employee of Novartis Pharmaceuticals.
CRYSTAL CITY, VA. — Aliskiren in combination with either hydrochlorothiazide or amlodipine reduced central systolic blood pressure significantly more than did amlodipine alone in an African American population, based on data from two studies of several hundred adults.
Findings from previous studies have suggested that cardiovascular morbidity might be more closely associated with central blood pressure than it is with systolic blood pressure, according to Dr. Keith Ferdinand of Emory University in Atlanta, and his colleagues.
Additional studies have shown that central blood pressure tends to be higher in healthy young African American men, compared with that in healthy young white men, the researchers noted in a poster at the meeting.
To compare the effects of a combination aliskiren/hydrochlorothiazide (HCTZ) in African Americans with stage II hypertension, Dr. Ferdinand and his colleagues reviewed a subset of patients from two safety and efficacy studies of aliskiren/HCTZ.
Overall, central systolic blood pressure was reduced by approximately 30 mm Hg from baseline in each study, the researchers said, which suggests that aliskiren combined with either a diuretic or calcium channel blocker might be equally effective in African American patients.
In study 1, which included 53 sites throughout the United States, 166 patients were randomized to 300 mg aliskiren/25 mg HCTZ, and 166 received 10 mg amlodipine.
In study 2, a total of 220 adults were randomized to receive 300 mg aliskiren/10 mg amlodipine, and 223 received 10 mg amlodipine.
In study 1, the mean reduction in the central measure of systolic blood pressure was significantly greater in the aliskiren/HCTZ group, compared with the amlodipine-only group (30.1 mm Hg and 21.2 mm Hg, respectively) after 8 weeks of treatment, the researchers noted.
Changes in the peripheral measure of systolic blood pressure were not significant in either of the groups.
In study 2, the mean reduction in the central measure of systolic blood pressure was significantly greater in patients in the aliskiren/amlodipine group, compared with the amlodipine-only group after 8 weeks of treatment (29.8 mm Hg and 24.2 mm Hg, respectively).
But in this study, the mean reduction in the peripheral measure of systolic blood pressure also was significant (34.1 mm Hg and 28.9 mm Hg, respectively).
Aliskiren-based combination therapy also reduced diastolic blood pressure in both studies, but the mean reductions only reached significance in study 2. In that study, the mean reductions in the central measure of diastolic blood pressure in the aliskiren/amlodipine group and the amlodipine-only group were 16.0 mm Hg vs. 9.9 mm Hg, respectively, and the mean reductions in the peripheral measure of diastolic blood pressure for the two groups were 14.3 mm Hg and 10.5 mm Hg, respectively.
The average age of the patients was 53 years, and approximately half were women.
Patients with type 1 diabetes or type 2 diabetes who took insulin were excluded, as were patients with a history of heart failure, myocardial infarction, or other heart problems within a year of the study.
Reports of adverse events were similar between the two groups in each study, and the most common adverse events included headache, diarrhea, nausea, hypokalemia, nasopharyngitis, upper respiratory tract infection, peripheral edema, and pain.