Cochrane Database of Systematic Reviews

Blood pressure guidelines – where are we now?

“…Other systematic reviews support NICE’s analysis about beta-blockers 8 , 9. In a meta-analysis of 13 randomised controlled trials (including ASCOT-BPLA) involving a total of 105,951 patients, the risk of stroke, but not myocardial infarction or all-cause mortality, was greater with beta-blockers than with other drugs (RR 1.16, 95% CI 1.04 to 1.30) 8.…”

“…However, the absolute difference in the incidence of stroke between treatments was small (3.18% with beta-blockers vs. 2.96% with other drugs) and was not adjusted for differences in blood pressure lowering between treatments. In a recent Cochrane review, beta-blockers reduced the risk of stroke compared with placebo or no treatment (four trials involving a total of 23,613 patients: 1.8% vs. 2.3% with placebo, RR 0.80, 95% CI 0.66 to 0.96) 9. This represents one less stroke for every 200 patients treated with a beta-blocker for around 5 years 9.…”

“…In a recent Cochrane review, beta-blockers reduced the risk of stroke compared with placebo or no treatment (four trials involving a total of 23,613 patients: 1.8% vs. 2.3% with placebo, RR 0.80, 95% CI 0.66 to 0.96) 9. This represents one less stroke for every 200 patients treated with a beta-blocker for around 5 years 9. However, a beta-blocker was less likely than a calcium channel blocker to prevent stroke (three trials, a total of 44,167 patients: absolute difference 0.6%, RR 1.24, 95% CI 1.11 to 1.40) or an ACE inhibitor or angiotensin-II receptor antagonist (two trials, a total of 9,951 patients: absolute difference 1.5%, RR 1.30, 95% CI 1.11 to 1.53) 9.…”

“…This represents one less stroke for every 200 patients treated with a beta-blocker for around 5 years 9. However, a beta-blocker was less likely than a calcium channel blocker to prevent stroke (three trials, a total of 44,167 patients: absolute difference 0.6%, RR 1.24, 95% CI 1.11 to 1.40) or an ACE inhibitor or angiotensin-II receptor antagonist (two trials, a total of 9,951 patients: absolute difference 1.5%, RR 1.30, 95% CI 1.11 to 1.53) 9. For comparisons with diuretics, heterogeneity between trials prevented meta-analysis.…”

Endpoints in asthma drug trials - what do they mean?

“…Other measures of lung function are less commonly used in trials. They include forced expiratory flow in the middle part of forced expiration (FEF 25-75 ), an indication of airflow in the small airways 14. Different studies report lung function parameters in different ways, making comparisons between studies difficult 14…”