Intraocular pressure-lowering effects of all commonly used glaucoma drugs: a meta-analysis of randomized clinical trials.

OBJECTIVE To estimate the intraocular pressure (IOP) reduction achieved by the most frequently prescribed glaucoma drugs and a placebo in a meta-analysis of randomized clinical trials. DESIGN Meta-analysis of randomized clinical trials. PARTICIPANTS Twenty-seven articles reporting on 28 randomized clinical trials. These articles reported 6953 participants for the trough and 6841 for the peak. METHODS Articles published up to December 2003 were identified in the following data sources: Medline, Embase, and the Cochrane Controlled Trials Register, and references from relevant articles. Over 85% of the patients had to be diagnosed with primary open-angle glaucoma (POAG) or ocular hypertension (OH), and articles had to be written in English, German, French, or Dutch. Quality of trials was assessed by a Delphi list with additions. The pooled 1-month IOP-lowering effect from baseline at peak and trough was calculated by performing meta-analysis using the random effects model. MAIN OUTCOME MEASURES Absolute and relative change in IOP from baseline, for peak and trough moments. RESULTS Relative IOP reductions from baseline [mean (95% confidence interval)] were -23% (-25% to -22%) for a peak and -20% (-23% to -17%) for a trough for 0.5% betaxolol; peak, -27% (-29% to -25%), and trough, -26% (-28% to -25%), for 0.5% timolol; peak, -22% (-24% to -20%), and trough, -17% (-19% to -15%), for 2.0% dorzolamide; peak, -17% (-19% to -15%), and trough, -17% (-19% to -15%) for 1.0% brinzolamide; peak, -25% (-28% to -22%), and trough, -18% (-21% to -14%) for 0.2% brimonidine; peak, -31% (-33% to -29%), and trough, -28% (-30% to -26%) for 0.005% latanoprost; peak, -31% (-32% to -29%), and trough, -29% (-32% to -25%) for 0.004% travoprost; peak, -33% (-35% to -31%), and trough, -28% (-29% to -27%) for 0.03% bimatoprost; and peak, -5% (-9% to -1%), and trough, -5% (-10% to -0%) for the placebo. The difference in absolute IOP reduction from baseline between timolol and prostaglandin analogs or prostamide varied from -0.4 to 0.1 mmHg at trough and from 1.0 to 1.5 mmHg at peak. Quality scores of included studies were generally high, a mean of 14.2 on a scale from 0 to 20 (interquartile range, 13-16). CONCLUSION This meta-analysis suggests that bimatoprost, travoprost, latanoprost, and timolol are the most effective intraocular pressure-reducing agents in POAG and OH patients.