Background
As the global burden of glaucoma continues to rise, evidence suggests factors beyond intraocular pressure contribute to its pathogenesis. Environmental pollutants are increasingly implicated in ocular disease, yet the association between dichlorophenol exposure and glaucoma remains unexamined. This study addresses this gap by analyzing NHANES data to investigate their relationship, providing new evidence for disease prevention and environmental intervention.
Methods
The data originated from the National Health and Nutrition Examination Survey (NHANES, 2005–2008). To explore the connection between urinary dichlorophenol levels and glaucoma, we conducted weighted logistic regression analyses. Additionally, to examine potential nonlinear associations, restricted cubic splines (RCS) were utilized. We further performed subgroup analyses to investigate interaction effects.
Results
There were 1,742 participants. The risk of glaucoma was significantly associated with higher ln-transformed urinary 2,4-dichlorophenol levels (OR = 1.39; 95% CI: 1.11–1.74; P = 0.002), as were Ln-transformed urinary 2,5-dichlorophenol levels (OR = 1.28; 95% CI: 1.09–1.51; P = 0.001). Participants in the third tertile of 2,4-dichlorophenol were at a greater risk for glaucoma compared to the first tertile (OR = 2.11; 95% CI: 1.07–4.17; P for trend = 0.042), according to the completely adjusted model. Similar results were observed for the levels of 2,5-dichlorophenol (OR = 2.15; 95% CI: 1.03–4.48; P for trend = 0.039). RCS demonstrated the nonlinear connection between urinary dichlorophenol levels (2,4-dichlorophenol and 2,5-dichlorophenol) and glaucoma risk (P for nonlinearity < 0.05).
Conclusions
Our results demonstrated a strong nonlinear positive association between urinary dichlorophenol levels and glaucoma risk. Given the global prevalence of dichlorophenols and the universal burden of glaucoma, these findings provide a valuable reference for international counterparts investigating similar environmental-ocular health links.