Effect of smoking on retina nerve fiber layer and ganglion cell-inner plexiform layer complex

The aim of this study is to show the effects of smoking on retina layers, especially retina nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer complex (GCIPL).

Participants smoking for more than 10 years at least 1 pack of cigarettes a day and a control group, both including participants between ages of 20 and 50 years with no other systemic or ocular diseases were studied. After normality tests, an independent sample t test was used to analyze the differences in age, sex, spherical equivalent (SE), intraocular pressure (IOP), axial length (AL), GCIPL and RNFL values between the groups.

There were 44 participants in each group. There were 32 (62.5%) men and 12(37.5%) women in smokers and 36 (77.88%) men and 8 (22.22%) women in control group. Mean ages were 39.85 ± 8.41 and 38.66 ± 10.47 years, mean spherical equivalent (SE) values were -0.15 ± 0.4 and 0 ± 0.29 dioptries in smokers and control groups, respectively. The IOP, AXL, GCIPL and RNFL values were 17.58 ± 3.41 mmHg, 23.69 ± 0.56 mm, 84.3 ± 5.83 μm and 92.3 ± 3.51 μm in the smokers group and 18.5 ± 2.91 mmHg, 23.45 ± 0.72 mm, 86.11 ± 8.02 μm and 97.66 ± 8.23 μm in the control group. The inferior, superior, nasal and temporal values of RNFL quadrants were 123.18 ± 26.14, 117.05 ± 5.51, 64.95 ± 8.67 and 63.5 ± 6.88 μm in the smokers group and 130.81 ± 11.8, 123.55 ± 11.03, 72.44 ± 9.84 and 58.44 ± 7.48 μm in the control group. There were no significant difference of age, sex, SE, IOP, AXL and GCIPL values between the smokers and control groups (p > 0.05). The mean RNFL was significantly thinner in the smokers group compared to controls (p = 0.03, independent t test). Inferior and superior quadrants of RNFL decreased in smokers group (p = 0.01 and p = 0.03, respectively) but temporal and nasal quadrants did not seem to be changed (p = 0.96 and p = 0.07, respectively).

Smoking may affect RNFL thickness but not GCIPL.