Impact of Smoking on Choroidal Microvasculature Dropout in Glaucoma

Abstract

Purpose : To investigate the effect of smoking history on MvD in primary open angle glaucoma (POAG) eyes.

Methods : In this retrospective study, POAG patients with at least one good quality optical coherence tomography angiography (OCT-A) scan and previous smoking data (i.e. negative or positive smoking history, smoking intensity [pack/year]) were enrolled. Area and angular circumference of MvD were analyzed on an OCT-A en-face choroidal vessel density map. Univariable and multivariable linear mixed effect models were constructed to identify the factors correlated with smoking intensity in both early and moderate-severe glaucoma.

Results : Two-hundred twenty-five eyes of 125 POAG patients were included in the analysis. Of them, 56 patients (33.9%) had positive history of tobacco consumption (21.8% smoked 0-10 packs/week, 21.8% smoked 10-20 pack/year and 56.4% smoked >20 pack/year). MvD was found in 37 (51.4%) eyes with positive history of smoking and in 69 (45.1%) eyes with no history of smoking (P= 0.394). No significant differences were found in MvD area and angular circumference between smokers and non-smokers (P=0.116 and P=0.064).
In a univariable model, sex, race, VF mean deviation (MD), MvD area and MvD angular circumference were significantly associated with smoking intensity (coefficient [95% CI): 9.22 (4.07,14.37), -5.16(-9.34, -0.99), 0.42 (0.80, 0.05); P=0.027, 18.75 (2.06, 35.43); P=0.028, and 0.07 (0.02, 0.13); P=0.012, respectively). In a multivariable model adjusting for age, sex, race, VF MD, MvD area remained significantly associated with smoking index (coefficient=16.41 (0.27, 32.56), P=0.046). When considering eyes with moderate-severe glaucoma, MvD area was significantly associated with the intensity of smoking (P=0.041 and 0.031, in univariable and multivariable models), whereas no significant association was found in early glaucomas (P=0.898 and P=0.234 in univariable and multivariable models).

Conclusions : In eyes with moderate-severe glaucoma, the area of MvD was larger in heavy smokers. As MvD is considered a parameter of impaired optic nerve perfusion, the intensity of smoking might contribute to glaucoma progression, especially in eyes with more severe disease.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

 

 

Figure 1. En-face choroidal vessel density map showing MvD in two patients with similar glaucoma severity: (a) non-smoker OAG patient (VF MD -9.85 dB ) with smaller MvD; (b) smoker OAG patient (28.2 pack/year) (VF MD -9.25) with larger MvD area.