Transient effects of smoking on the eye

Purpose To investigate the immediate short-term effects of smoking in habitual smokers, on the tear film, pupil size and accommodative ability of the human eye. Methods Habitual smokers were tested within 5 min of smoking a cigarette. The tear film analysis was undertaken using tear break–up time (TBUT), tear lipid layer thickness and tears meniscus height (TMH) measurements. Three different ways of tear break–up time (TBUT) were used; using fluorescein; a non-invasive TBUT using tearscope; and a video captured method with a corneal topographer. Pupil size was measured objectively using the video capture on the corneal topographer. Accommodative ability was checked by performing a ‘push up test' to measure amplitudes of accommodation (AoA) and by measuring defocus curves. Results Forty-five participants were enrolled (mean age 22.0 ± 4.4 years). TBUT was reduced after smoking a cigarette with all three assessment methods and this reduction was statistically significant (p 0.05). Conclusion The study shows that there is an immediate adverse effect of smoking on TBUT and AoA which seems to be very transient