Reduced 25-hydroxyvitamin D concentration in the aqueous humor of cataract patients with open-angle glaucoma

Abstract

Previous epidemiological studies have demonstrated that the lower serum concentration of vitamin D was associated with elevated risk of open-angle glaucoma (OAG). However, few studies have examined the association between aqueous humor vitamin D concentrations and OAG. Hence, we investigated the relationship between 25-hydroxyvitamin D (25(OH)D) concentrations in aqueous humor and OAG. We measured 25(OH)D concentrations in aqueous humor and serum of 126 patients who underwent cataract surgery. 36 were patients with OAG and 90 were control patients. The 25(OH)D concentrations were measured using Elecsys Vitamin D Total Kits with the Cobas e602 module (Roche Diagnostics, Mannheim, Germany), an electrochemiluminescence assay. Multiple linear regression analysis was performed to investigate factors associated with serum and aqueous humor 25(OH)D concentrations. Patients with OAG had significantly lower 25(OH)D concentrations in aqueous humor than control patients. Serum 25(OH)D concentrations were higher in patients with OAG than in the control, but this was not statistically significant. 25(OH)D concentrations in aqueous humor of patients with OAG were significantly associated with axial length but not with glaucoma severity, which was determined by the retinal nerve fiber layer thickness or mean deviation. Vitamin D concentrations in aqueous humor of patients with OAG were significantly lower than those in patients without OAG.