Ten trials (3,255 participants) were included in the review. Nine were of parallel design (3,229 participants) and one crossover (26 participants). Two trials compared aliskiren with losartan, three compared aliskiren with valsartan, and five compared aliskiren with irbesartan.
Eight trials scored 5 points for quality, one scored 4 points and one scored 3 points. All scored positive for randomisation, intention-to-treat analysis, completeness of follow-up, and description of withdrawals. Generation of random sequence was appropriate in eight trials, but unable to be assessed in two. Follow-up ranged from four to 12 weeks.
There was no difference between aliskiren and angiotensin receptor blockers in the reduction of mean clinic systolic or diastolic blood pressure (none trials), ambulatory systolic or diastolic blood pressure (four trials), therapeutic response rate (four trials) or blood pressure control rate (seven trials). Subgroup analyses showed no difference in mean clinic systolic or diastolic blood pressure compared with each angiotensin receptor blockers individually. Sensitivity analyses showed no difference in effect on clinic blood pressure for all analyses.
Compared with angiotensin receptor blockers (valsartan, irbesartan and losartan, combined or individually) aliskiren showed no difference in the incidence of adverse effects.
Funnel plot indicated an absence of publication bias.