Effect of smoking on meibomian gland among Nepalese population

Purpose of study: To investigate the effects of cigarette smoking on meibomian gland and tear function test. Methods: It was a hospital-based cross-sectional study, which enrolled examined 30 subjects with a smoking history of at least 1 year (study group) alongside 25 healthy non-smokers (control group). Each participant’s symptoms were assessed using the Ocular Surface Disease Index (OSDI) questionnaire. A comprehensive ophthalmological evaluation followed, which included the non-invasive tear breakup time (NITBUT) and Schirmer test (with anesthesia). Additionally, we conducted a detailed analysis of the meibomian glands in both the upper and lower eyelids using meibography, employing the advanced Sirius anterior segment analysis system. Results: Participants in the study group averaged a smoking history of 6.94 ± 6.73 pack years. The mean OSDI score was 36.45 ± 10.60 in the study group, compared to 31.41 ± 8.12 in the control group ( P = 0.05). For the NITBUT and Schirmer test, the study group recorded values of 9.54 ± 5.89 seconds and 14.77 ± 9.39 mm, respectively, while the control group showed 9.95 ± 6.15 seconds and 19.08 ± 7.08 mm ( P = 0.85 and P = 0.03, respectively). Upper lid meibography revealed a 55.40 ± 10.10% gland loss in the study group, significantly higher than the 46.33 ± 14.70% observed in the control group ( P = 0.01). However, no statistically significant difference was found in lower lid meibomian gland loss between the groups, with the study group at 54.08 ± 9.71% and the control group at 51.41 ± 17.24% ( P = 0.49). Conclusion: Smoking results in meibomian gland damage which may be a risk factor for dry eye. In cases of ocular surface disorders related to chronic smoking, meibomian gland damage should be taken into consideration.