Sasan Mojimi, MD
Image Credit: Healey Eye Institute
A retrospective cross-sectional study found that smoking intensity was associated with greater rates of choroidal microvascular shedding in patients with glaucoma, especially those with moderate to severe disease.1
The research team, led by Sasan Moghimi, MD, Department of Ophthalmology, UC San Diego Healey Eye Institute, said these data point to a potential role of smoking in the pathogenesis of glaucoma.
“In the current study, smoking intensity was associated with the area of microvasculature shedding, suggesting that long-term smoking may affect choroidal and deep optic nerve microvasculature,” the researchers wrote.
Smoking is a known risk factor for the development and progression of various eye diseases, including age-related macular degeneration (AMD), cataracts, and retinal vein occlusion (RVO). However, its role in glaucoma is unclear—some literature suggests that smoking is not associated with glaucoma, while other studies report that smoking increases the risk of progression of open-angle glaucoma.2
The disease is characterized by loss of retinal ganglion cells, resulting in loss of function and deterioration of visual field.3 Choroidal microvascular loss is a localized parapapillary perfusion defect that can be identified using optical coherence tomography angiography (OCTA). In this cross-sectional analysis, Moghimi and colleagues evaluated the effect of smoking on choroidal microvasculature detachment in patients with primary open-angle glaucoma.1
This analysis documents the self-history of tobacco consumption. Smoking intensity was quantified using the pack-year index, defined as consumption of 20 cigarettes per day in a year. Eyes were assessed as having glaucoma based on ≥2 consecutive, reproducible abnormal visual field test results and evidence of glaucomatous optic neuropathy.
Multivariable linear mixed-effects models were used to determine the effect of smoking intensity on choroidal microvasculature shedding and angular circumference. Covariates included age, sex, race, self-reported diabetes, and visual field mean deviation (MD). A sensitivity analysis was performed by classifying glaucoma severity as determined by visual field MD.
A total of 223 eyes of 163 patients with primary open-angle glaucoma who had completed OCTA imaging were included. Among these patients, 55 (33.7%) patients had a history of tobacco consumption (21.8%, 0-10 pack-years; 21.8%, 10-20 pack-years; 56.4%, >20 pack-years). Eyes with a history of smoking have a higher rate of moderate and advanced glaucoma compared with eyes without a history of smoking (ask = .004).
After analysis, choroidal microvessel detachment was observed in 37 eyes (51.4%) with a history of smoking and in 67 eyes (44.4%) with no history of smoking.ask = .389). Analysis showed that compared with non-smokers, smokers had larger areas of capillary shedding and wider angular circumferences (ask = .068 and ask = .046, respectively).
Furthermore, in the multivariable model, after adjusting for relevant variables, greater smoking intensity was associated with greater microvascular shedding area (0.30 (95% CI, 0.01 to 0.60) per 0.01 mm2 per pack-year; ask =.044).
In eyes with moderate to severe glaucoma (MD <−6) (n = 104), smoking intensity was associated with greater area of microvascular loss (0.47 per 0.01 mm per 10 pack-years (95% CI, 0.11 to 0.83 ); ask =.011). However, in eyes with early-stage glaucoma (MD ≥-6) (n = 102), no association was observed (–0.08 (95% CI, –0.26 to 0.11), ask =.401).
Based on these data, Moghimi and colleagues noted that the relationship between smoking intensity and microvasculature shedding depends on the severity of the disease. They noted that this association may be due to severely impaired microvascular circulation in eyes with moderate to advanced glaucoma.
“A history of heavy smoking may lead to further deterioration of microvasculature, leading to more extensive glaucomatous damage,” the researchers wrote. “Conversely, in mildly glaucomatous eyes with healthier microvasculature, smoking intensity may not have a substantial impact on choroidal perfusion. damage.”
refer to
- Nishida T, Micheletti E, Latif K, Du KH, Weinreb RN, Moghimi S. Effect of smoking on choroidal microvascular shedding in glaucoma: a cross-sectional study. BMJ Open Ophthalmology. 2023;8(1):e001421. doi:10.1136/bmjophth-2023-001421
- Nishida T, Mahmoudinezhad G, Weinreb RN, et al. The retinal nerve fiber layer gradually becomes thinner in smoking and glaucoma. Br J Ophamol 2022: bjophamol-2022-321237. doi:10.1136/bjo-2022-321237
- Weinreb RN, Leung CKS, Crowston JG, et al. Primary open-angle glaucoma. Nat Rev Dis Primer 2016;2:16067. doi:10.1038/nrdp.2016.67