Socioeconomic Deprivation Amplifies the Risk of Glaucoma From Ultrafine Particle Exposure: Evidence From the Retrospective Cohort Study.

Objective

Evidence has revealed that socioeconomic deprivation (SED) could enhance the hazard of particulate matter on health. However, the relationship between SED, ultrafine particles (UFPs), and the development of glaucoma remains uninvestigated. We aim to estimate the association between UFPs, SED, and glaucoma. Additionally, the potential modifiers of this association are also explored.

Design

A population-based retrospective cohort study.

Participants

This study contained 379,724 participants aged exceeded 50 years without glaucoma at baseline from the UK Biobank.

Methods

UFPs were estimated with the ECHAM/MESSy Atmospheric Chemistry model. SED was assessed via Townsend deprivation index (TDI), with higher scores indicating greater deprivation. Cox proportional hazards models were conducted to evaluate the association between SED, UFPs, and glaucoma. Potential effect modifiers of UFP-glaucoma association were further explored.

Main outcome measures

The primary outcome was the development of glaucoma.

Results

During a median follow-up of 12.6 years, 10,950 participants were diagnosed with glaucoma. Higher UFP exposure was positively associated with glaucoma risk, and this association was significantly enhanced among individuals with higher TDI (P interaction = .004). Compared with the lowest quartile, the hazard ratios (HRs) for the highest quantile were 1.16 (1.08, 1.24) in total population, 1.10 (1.00, 1.21) in the low-TDI group, and 1.21 (1.09, 1.34) in the high-TDI groups. Stratified analyses showed that only greenness exposure attenuated the hazard of UFPs on glaucoma, with a Normalized Difference Vegetation Index higher than 0.6 reversing the association to nonsignificant, especially in the high-TDI group.

Conclusions

Our findings provide the first evidence that SED enhances the detrimental effect of UFPs on glaucoma risk, exacerbating health inequality. Targeted strategies aimed at increasing greenness exposure may be effective in mitigating these disparities, especially in underdeveloped regions.