Effect of Smoking on Retinal Thickness and Vascular Density in Thyroid Eye Disease

PURPOSE: To evaluate the effect of smoking on retinal thickness and macular and peripapillary vascular density in thyroid eye disease (TED). METHODS: In this cross-sectional study, subjects diagnosed with TED were analyzed in three groups: smokers, passive smokers, and non-smokers. Ganglion cell complex thickness, total retinal thickness, macular superficial vascular plexus densities, deep vascular plexus densities, optic nerve head, and radial peripapillary capillary density were measured in each group. RESULTS: Twenty-two eyes (21.6%) of active smokers, 11 eyes (10.8%) of passive smokers, and 69 eyes (67.6%) of non-smokers constitute the study subjects. Twenty-one eyes (12.6%) had active status (clinical activity score ≥3), 77 eyes (46.1%) were neither active nor compressive, four eyes (2.4%) of two patients constituted the compressive group. Age and disease activity adjusted analysis was performed. Ganglion cell complex thickness of smokers was significantly higher than non-smokers in the inferior hemi-parafoveal sector (p = 0.04). Active smokers had significantly higher (p < 0.01) retinal thickness in all sectors compared to non-smokers, except the foveal sector. Smokers had lower superficial vessel density in the superior parafoveal sector compared to non-smokers (p = 0.04). Considering deep vessel densities between smokers and non-smokers, no significant difference was observed. Radial peripapillary capillary densities (significant difference was observed in the whole image and infranasal peripapillary sector), Macular vascular densities (significant difference was observed in parafoveal sectors), and optic nerve head (not reaching statistical significance level in any sectors) were highest in passive smokers. CONCLUSIONS: Smoking is associated with increased total retinal thickness. Macular vascular densities were not different between smokers and non-smokers in TED.