Greenspace exposure and the incidence of ocular and adnexal diseases: novel findings from a large prospective cohort study
image: The models were adjusted for age, gender, ethnicity, indices of Thompson deprivation, employment status, household income, and qualifications. HR, hazard ratio; CI, confidence interval. The P-overall value indicated the significance level of the overall association of all factors in the model (significant if less than 0.05). The P-nonlinear value indicated the significance level of the nonlinear association in the model (significant if less than 0.05). (A) Disorders of eyelid, lacrimal system, and orbit. (B) Disorders of conjunctiva. (C) Disorders of sclera, cornea, iris, and ciliary body. (D) Disorders of lens. (E) Disorders of choroid and retina. (F) Glaucoma. (G) Disorders of vitreous body and globe. (H) Disorders of ocular muscles, binocular movement, accommodation, and refraction. (I) Visual disturbances and blindness.
Credit: Bo-Yi Yang
Researchers from Sun Yat-sen University, Imperial College London, Guangzhou Medical University, and collaborating institutions have published a study in Health Data Science examining residential greenspace exposure and incident ocular and adnexal diseases in UK Biobank. The findings show that associations differ by disease subtype, suggesting that the health implications of greenspace should be assessed with outcome-specific care.
Ocular and adnexal diseases are important causes of vision impairment, but longitudinal evidence on greenspace and these outcomes has been limited. Greenspace may be associated with eye health through lower air pollution and more physical activity, while it may also increase exposure to pollen allergens or ultraviolet radiation; its overall associations may therefore vary.
The prospective study included 241,576 UK Biobank participants at baseline from 2006 to 2010. The investigators assessed the percentage of greenspace within residential buffers and followed incident ocular and adnexal disease subtypes. Comparing the highest with the lowest quartile of greenspace percentage within a 300-m buffer, higher exposure was associated with lower incidence of lens disorders (hazard ratio [HR], 0.931; 95% confidence interval [CI], 0.896 to 0.968) and a borderline lower incidence of choroid and retina disorders (HR, 0.935; 95% CI, 0.874 to 1.000). The association for lens disorders was partly mediated by physical activity and air pollution. In contrast, higher greenspace was associated with a higher incidence of eyelid, lacrimal system, and orbit disorders (HR, 1.082; 95% CI, 1.018 to 1.150); conjunctiva disorders were more frequent in the first versus third quartile comparison (HR, 1.129; 95% CI, 1.027 to 1.241).
The findings suggest that greenspace-related strategies should not assume identical effects across eye disease outcomes. Because this is an observational cohort analysis, the results describe associations rather than causation; findings across settings, greenspace types, and behavioral patterns require further study.