Impact of Chronic Smoking on Meibomian Gland Dysfunction

PURPOSE: The aim of this study was to explore the relationship between chronic cigarette smoking and meibomian gland dysfunction (MGD). METHODS: This study enrolled 322 smokers with MGD and 2067 non-smokers with MGD. All enrolled subjects were tested in the following sequence: Ocular Surface Disease Index (OSDI), tear film breakup time (TBUT), corneal fluorescein staining (CFS), Schirmer I test (SIT)and finally slit-lamp microscope examination of lid margin abnormalities, meibomian gland expression as well as meibum. RESULTS: Compared with the MGD patients without smoking, the MGD patients with smoking had significantly increased scores of lid margin abnormality and meibum (P<0.01 for each comparison). No significant difference was noted in OSDI, TBUT, CFS, SIT or the score of Meibomian gland expressibility between the smokers and non-smokers (P>0.05 for each comparison). In the smokers, the smoking index was significantly correlated with the scores of lid margin abnormality (Both sexes, R = 0.19, P<0.01; Male, R = 0.18, P<0.01) and meibum (Both sexes, R = 0.29, P<0.01; Male, R = 0.20, P<0.01), whereas it was not significantly correlated with OSDI, TBUT, CFS, SIT or score of Meibomian gland expressibility (P>0.05 for each comparison). CONCLUSION: The findings of this study suggest chronic smoking might be associated with MGD.