Comparing two different daily disposable lenses for improving discomfort related to contact lens wear.

Purpose: This study aimed to compare two daily disposable lenses to reduce lens-induced discomfort (CLD) among different populations of symptomatic wearers.
Methods: This was a multicenter, crossover, study. Subjects were contact lens wearers reporting CLD. Subjects (76) were randomly assigned to wear Nelfilcon A (NF) then Delefilcon A (DF)- group A- or vice-versa (group B). Tear break-up time (TBUT), corneal (CS) and conjunctival staining (CJS) were graded at every visit. Subjects'symptoms were evaluated with Contact Lens Dry Eye Questionnaire (CLDEQ-8) and a research questionnaire (Université de Montréal).
Results: Compared to baseline (BL), TBUT did not vary (BL) 6.7+2.1s vs. 6.7+1.8s (NF) vs. 6.4+1.9 (DF) (F=1.69; p=0.201) NF wearers were more at risk of developing moderate CJS (odds ratio 14.324; 95% CI 3.103-66.126) and more likely to show increased CS (odds ratio 8.754; 95% CI 2.181-35.146). Comfortable hours of wear reported at BL (7.6+2.3h) did not improve significantly with NF lenses (8.5+ 2.6h; F=1.095; p=0.394) but increased by 22% with DF lenses (10.7+3.0h; F=2.434; p=0.031). The total CLDEQ-8 score was improved with DF lenses (BL 17.2 vs. NF 16.1, p=0.397; vs. DF 8.3, p<0.001), especially on more symptomatic subjects. In the end, 92% of patients preferred to switch over DD lenses, 78% selecting DF material for the future.
Conclusion: Outcome from switching CLD wearers to DD lenses is material related. It seems that initial severity of the symptoms could be also a factor to consider.
(Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)