Lung function a potential biomarker for glaucoma

Lung function measures are associated with risk of glaucoma, indicating their potential role as biomarkers for the optic neuropathy with a devastating visual impact, researchers from the Chinese University of Hong Kong, Princes of Wales Hospital and Hong Kong Eye Hospital have reported.

In a cross-sectional study, the researchers investigated associations of lung function with glaucoma and related traits using data from 85,369 participants (mean age, 56.6 years; female, 55.7 percent) with lung function measurements at baseline from the UK Biobank cohort. The primary outcome of glaucoma was based on self-reported diagnoses and Hospital Episode Statistics data. [Invest Ophthalmol Vis Sci 2025;66:48]

The large-scale analysis revealed significant inverse associations between lung function measures and glaucoma, with odds ratios (ORs) of 0.86 (95 percent confidence interval [CI], 0.81–0.91) for forced vital capacity (FVC), 0.81 (95 percent CI, 0.75–0.87) for forced expiratory volume in 1 second (FEV₁), 0.49 (95 percent CI, 0.29–0.84) for FEV₁/FVC ratio, and 0.994 (95 percent CI, 0.992–0.996) for Global Lung Initiative (GLI)–predicted FEV₁ (all p<0.05).

Compared with the highest quartile of lung function measures, ORs for the lowest quartile were 1.51 (95 percent CI, 1.31–1.74; p=7.6 x 10^-8) for FVC, 1.58 (95 percent CI, 1.37–1.81; p=4.7 x 10^-10) for FEV₁, 1.20 (95 percent CI, 1.08–1.34; p=0.002) for FEV₁/FVC ratio, and 1.30 (95 percent CI, 1.17–1.44; p=8.8 x 10^-7) for GLI-predicted FEV₁.

Similar associations were found between impaired lung function and glaucoma, with ORs of 1.22 (95 percent CI, 1.11–1.33; p=1.2 x 10^-5) for FEV₁ <80 percent of GLI-predicted value, and 1.13 (95 percent CI, 1.03–1.24; p=0.01) for FEV₁/FVC ratio <0.7.

However, subgroup analysis by sex showed that impaired lung function was significantly associated with glaucoma in males, but not in females.

“Although hormonal factors and differences in airway geometry between men and women may contribute to variations in the association between lung function and glaucoma, the precise nature of these differences remained largely unknown,” the investigators noted. [Pharmaco Ther 2015;150:94-108]

Other possible explanations for the between-sex difference include the association of hormone replacement therapy with better FEV₁ and FVC in elderly women, the greater effect of inflammatory processes on lung function in males than females, and potential differences in cumulative effects of smoking on lung function between males and females, given the higher prevalence of smoking observed in male vs female participants in the current study. [Pulm Ther 2023;9:461-477; Public Health 2020;183:88-93; Respir Med 2013;107:91-97]

The study’s results also showed that lower FVC, FEV₁, GLI-predicted FEV₁ and FEV₁/FVC ratio were associated with lower intraocular pressure, thinner macular retinal nerve fibre layer thickness, and thinner ganglion cell–inner plexiform layer thickness (all p<0.05).

However, Mendelian randomization analyses did not reveal any significant causal relationship between lung function measures and primary open-angle glaucoma.

“Lower FVC, FEV₁ and FEV₁/FVC ratio, as well as impaired lung function, are potential biomarkers for glaucoma risk. These findings may facilitate clinical strategies for glaucoma management, particularly for individuals with impaired lung function,” the investigators concluded.