RT Journal Article
SR Electronic
T1 Tear neuromediators in eyes on chronic topical antiglaucoma therapy with and without BAK preservatives
JF British Journal of Ophthalmology
JO Br J Ophthalmol
FD BMJ Publishing Group Ltd.
SP bjophthalmol-2019-314234
DO 10.1136/bjophthalmol-2019-314234
A1 Vanathi Murugesan
A1 Roopa Dwivedi
A1 Manu Saini
A1 Viney Gupta
A1 Tanuj Dada
A1 S Vivekanandhan
YR 2019
UL http://bjo.bmj.com/content/early/2019/08/04/bjophthalmol-2019-314234.abstract
AB Purpose To evaluate tear neuropeptides (NPs) (vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), calcitonin gene-related peptide (CGRP), substance P (SP), nerve growth factor (NGF)) in chronic ocular topical hypotensive therapy with and without benzalkonium chloride (BAK) preservative.Methods A comparative, open label, cross-sectional study of patients using antiglaucoma medications for >6 months with BAK (group I), without BAK (group II) and controls was done. Tear NPs (ELISA), ocular surface evaluation tests (tear breakup time (TBUT), Schirmer’s test, corneal and conjunctival staining score) and confocal central corneal subbasal nerve fibre layer (SBNFL) imaging was done.Results Of 153 eyes evaluated, group 1 (82 eyes (41 patients; mean age 48±14.5 years)) and group 2 (71 eyes (36 patients; mean age 43.11±15 years)) were on therapy for a mean duration of 10.05±2.0 and 9.67±2.3 months, respectively. Tear analysis showed elevated SP and NGF (p<0.01); decreased CGRP (p=0.03), VIP and NPY (p<0.01) compared with controls (n=30, mean age 29.33±5.7 years). Tear NP levels (SP (p=0.1), NGF (p=0.33), CGRP (p=1), VIP (p=0.87), NPY (p=0.83)) and SBNFL (p=0.09) were comparable in both groups. There was no correlation seen between tear NP levels and clinical tests and SBNFL.Conclusion Our study analysis points towards altered tear NP levels in eyes on chronic topical hypotensive therapy in comparison with controls with no significant difference in tear NP levels and central corneal SBNFL density between the BAK preservative and BAK-free antiglaucoma therapy.