Influence of benzalkonium chloride in anti-glaucoma medications on intraocular pressure and ocular surface: a Meta-analysis

Objective

To evaluate the influence of benzalkonium chloride (BAK) in anti-glaucoma medication on intraocular pressure and ocular surface.

Methods

A Meta-analysis was performed.The literature about anti-glaucoma medications published in PubMed, EMbase, Cochrane Library from January 1, 2000 to December 31, 2016 were comprehensively searched to identify eligible studies.Randomized controlled trials (RCT) for intraocular pressure and ocular surface disease in anti-glaucoma eye drops with or without BAK in various types of glaucoma or ocular hypertension patients aged >18 years were collected.EXCEL tables were used to count the relevant data and Cochrane collaboration’s tool was used to assess the risk of bias system and to evaluate the quality of studies.RevMan 5.3 and Comprehensive Meta Analysis (CMA)V3 were used to perform the Meta-analysis of all RCT.

Results

Thirteen RCTs were incorporated.With BAK or without BAK, anti-glaucoma eye drops could efficiently decrease intraocular pressure, meanwhile this comparison had no significant difference (SMD: -0.00, 95% CI: -0.063-0.063, P=0.99, I²=0%). Adverse events including conjunctival hyperemia, dry eye and keratitis between the two groups were analyzed.During the follow-up period, conjunctival hyperemia, dry eye and keratitis were the main adverse reactions.A random effect model was used for conjunctival hyperemia Meta-analysis, and the fixed effect model was used for dry eye and keratitis Meta-analysis.The combined effect values of conjunctival hyperemia, keratitis and dry eye were OR=1.163, 95%CI: 0.896-1.509, P=0.257, I²=51.6%; OR=1.15, 95%CI: 0.76-1.76, P=0.50, I²=0%; OR=1.13, 95%CI: 0.79-1.61, P=0.51, I²=40%.Systematic comparison result showed that there were no statistically significant differences in the three adverse reactions between the two groups (all at P>0.05).

Conclusions

This Meta-analysis indicates that the reduction in intraocular pressure achieved by BAK-free eye drops is equivalent to the effect of eye drops with BAK, and the short term use of eye drops with BAK doesn’t change the incidence of conjunctival hyperemia, keratitis and dry eye.