Smoking may damage to the lipid layer of the ocular surface

Cigarette smoking may damage the precorneal tear film lipid layer, threatening stability and causing dry eye symptoms, researchers say.

Dilek Dursun Altinors, MD, and colleagues studied the effects of smoking on ocular surface and precorneal tear film, corneal and conjunctival sensitivity measurements and tear function tests of 60 cigarette smokers and 34 healthy people. Ocular surface vital fluorescein staining, conjunctival impression cytology and DR-1 tear film lipid layer interferometry also were studied. A subjective questionnaire about foreign-body sensation, burning or stinging, photophobia and ocular fatigue was also administered to both groups.

Damage was observed in the lipid layer in cigarette smokers as grade 3 or 4 dry eye changes, assessed by interferometry and frequent areas where lipid does not spread over the corneal surface, the study authors said. Clinical questionnaire scores support this claim and other clinical parameters found in the results, according to the study. Those who smoked expressed dry eye clinical signs, such as scratchiness, foreign-body sensation, burning and grittiness, compared with non-smokers.

Further studies are needed to assess the relationship between active and passive smoking, and “the effects of cigarette smoking on the ocular surface on a molecular basis in terms of free radicals,” researchers said.

The results of this study were published in the American Journal of Ophthalmology.