Effectiveness of using preservative-free artificial tears versus preserved lubricants for the treatment of dry eyes: a systematic review

This systematic review aimed to assess the effectiveness of using preservative-free artificial tears versus preserved lubricants for the treatment of dry eyes in Universidade Federal de Alagoas (PROSPERO 2018 CRD42018089933). Online databases were searched (LILACS, EMBASE, MEDLINE, and CENTRAL) from inception to April 2018; references from included papers were also searched. The following keywords were used: lubricants OR artificial tears OR artificial tears, lubricants AND dry eye OR dry eye syndrome OR syndromes, dry eye OR dry eyes. Among the 2028 electronic search results, 29 full papers were retrieved and four were considered relevant. The number of participants from these studies ranged from 15 to 76. Meta-analysis was possible for the following outcomes: score of symptoms according to the Ocular Surface Disease Index - Allergan (OSDI), tear secretion rate using the Schirmer test, tear evaporation rate using the tear film breakup time test, burning, foreign body sensation, and photophobia. No statistically significant difference was observed between the two groups, and no side effects were attributed to the interventions. Evidence proving that preservative-free artificial tears are more effective than preserved artificial tears is lacking.