Abstract
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 < 0.001). A reduction in lipid layer thickness was seen after smoking a cigarette with both methods used and was statistically significant (p < 0.01). A significant reduction in pupil size (p < 0.01) and in AoA (p < 0.001) was observed after smoking a cigarette. The difference in TMH and defocus curves, before and after smoking, were not 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.
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 < 0.001). A reduction in lipid layer thickness was seen after smoking a cigarette with both methods used and was statistically significant (p < 0.01). A significant reduction in pupil size (p < 0.01) and in AoA (p < 0.001) was observed after smoking a cigarette. The difference in TMH and defocus curves, before and after smoking, were not 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.
| Original language | English |
|---|---|
| Article number | 101595 |
| Journal | Contact Lens and Anterior Eye |
| Volume | 45 |
| Issue number | 5 |
| Early online date | 6 Apr 2022 |
| DOIs | |
| Publication status | Published - Oct 2022 |
Bibliographical note
© 2022 The Authors. Published by Elsevier Ltd on behalf of British Contact Lens Association. This is an open access article under the CC BY-NC-ND licence 4.0Keywords
- Pupil
- Smoking
- Tear break–up time
- The amplitude of accommodation