Tobacco Effects On Ocular Surface, Meibomian Glands And Corneal Epithelium And The Benefits Of Treatment With A Lipid Based Lubricant

Our aim was to evaluate the ocular surface in chronic smokers and to assess the benefit of sodium hyaluronate (SH) versus semi-fluorinated alkane (SFA) eyedrops on tear film, meibomian glands and corneal epithelial thickness (CET).

Ophthalmology Department of Hospital Garcia de Orta, Almada, Portugal.

This prospective randomized single blinded study included smokers, who applied one eyedrop of HyabakÒ on one eye (SH group) and one eyedrop of EvotearsÒ on the fellow eye (SFA group) 4 times daily for 2 months, and age-matched non-smokers. Ocular surface parameters, including Tear Film Break-up Time Test (TBUT) and Corneal Fluorescein Staining (CFS) score, lipid layer thickness (LLT), meibography (LipiviewÒ) and CET measurements (Cirrus HD-5000Ò) were assessed at baseline and after treatment. 

Seventy-eight eyes were included in Smokers group, 39 in SH subgroup and 39 in SFA subgroup, and 42 eyes in Control group. At baseline, Smokers group had a higher prevalence of dry eye (100% vs 0%, p<0.001) and of meibomian gland disfunction (MGD), and lower CET measurements than controls (p<0.05). TBUT, CFS and LLT (Controls vs SFA group: 64.02±1.87 vs 49.56±4.33nm, p=0.05) improved in SFA subgroup after treatment, but not in SH subgroup, and became equivalent to those of controls. Prevalence of dry eye decreased in Smokers group after treatment (Controls vs SH group vs SFA group: 0 vs12.82 vs 16.26%, p>0.05). Meibomian gland morphological parameters and CET did not improve after treatment (p<0.05).

Smoking is associated with dry eye, MGD and corneal epithelial thinning, that seem to be only partially reversible with topical lubricants, preferably SFA.