Eighteen trials were included in the review (n=678 patients). Eleven were randomised controlled trials and seven were controlled trials. Eight trials received a Jadad score of 4 or 5 out of 5 points; the rest scored of 2 or less. Four trials were double blinded. Eight trials had adequate reporting of allocation concealment.
Angiotensin receptor blockers/angiotensin-converting enzyme inhibitors: Pooled results based on six trials (n=238 patients, including one trial with available IPD) indicated statistically significantly reduced portal pressure in patients who received the treatment compared with placebo or no treatment (WMD -3.81mmHg, 95% CI -5.85 to -1.78; I2=95.7%). Pooled results of four trials (three trials with available IPD) indicated no significant difference in portal pressure in patients who received angiotensin receptor blockers/angiotensin-converting enzyme inhibitors compared with beta-blockers (I2=53.3%); however, for the three trials with IPD, the differences were statistically significant (WMD 1.70mmHg, 95% CI 0.45 to 2.95; I2=0%), favouring beta-blockers over angiotensin receptor blockers/angiotensin-converting enzyme inhibitors.
Aldosterone antagonists: Two trials that compared the aldosterone antagonist spironolactone with placebo were pooled to produce a borderline statistically significant result favouring spironolactone (WMD -1.3mmHg, 95% CI -2.6 to 0.04). Results were not pooled for aldosterone antagonists compared with other therapies due to substantial clinical variation in the control groups. Results for individual trials were reported.
Sensitivity analyses: Two trials that compared angiotensin receptor blockers/angiotensin-converting enzyme inhibitors with either placebo or no treatment, and that had a Jadad score over 3, were pooled. No statistical heterogeneity was identified (I2=0%); The results were still statistically significant and in favour of angiotensin receptor blockers/angiotensin-converting enzyme inhibitors. The results were not significantly altered by using fixed-effect rather than random-effects models.
Adverse effects were reported.