African Descent and Glaucoma Evaluation Study (ADAGES) III: Vitamin D Levels are Associated with Severity of Primary Open Angle Glaucoma (POAG) in African

Abstract

Purpose : To evaluate possible association between serum Vitamin D levels and POAG and in a cohort of patients of African descent (AD).

Methods : A subset of the ADAGES III cohort, consisting of 201 patients with a diagnosis of POAG and 80 age-matched normal controls of self-reported AD, were included in this analysis. Blood samples and family history were obtained from each patient. All patients with a diagnosis of POAG had glaucomatous visual field damage or an optic disc photograph or clinical drawing clearly indicating POAG. Control subjects had intraocular pressures ≤ 21 mm Hg, no evidence of glaucomatous optic neuropathy based on a clinical exam, and no family history of POAG in 1^st degree relatives. POAG patients were classified into ‘mild’ and ‘severe’ phenotypes based on the severity of their visual field damage, and were matched for age, gender, and history of hypertension and diabetes. Serum 25 (OH) Vitamin D levels were measured by ELISA. Association of serum Vitamin D levels with the development and severity of POAG was tested by ANOVA and paired t-Test.

Results : The early glaucoma group (‘mild’) comprising 89 subjects had a visual field mean deviation (MD) of better than -4.0 dB. The advanced glaucoma group had 112 subjects with visual field MD or worse than -10 dB. Comparison of the levels of serum Vitamin D between the mild, severe and control groups by ANOVA showed a significant difference among the three groups (p=0.016). Pair-wise t-test revealed that the mean (95% CI) levels of Vitamin D of subjects in the control (6.21±4.04 pg/mL) and mild phenotype (6.24±3.52 pg/mL) groups are significantly different from the levels observed in subjects with severe phenotype (5.01±2.82 pg/mL) (p=0.020 and 0.011, respectively). Whereas, the mean levels of serum Vitamin D in controls is not significantly different from the subjects with the mild phenotype

Conclusions : In this AD cohort, lower serum levels of vitamin D were present in subjects with advanced glaucoma compared to early glaucoma and normal subjects.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.