Levels of plasma homocysteine in pseudoexfoliation glaucoma

Background: To examine levels of serum homocysteine (Hcy), vitamin B12 and folic acid in patients with pseudoexfoliation glaucoma (PEXG), primary open-angle glaucoma (POAG), and healthy control subjects. Methods: This study included 36 patients with PEXG, 40 with POAG, and 40 age-matched healthy subjects. Fasting plasma Hcy concentrations and levels of serum vitamin B12 and folic acid were measured using competitive chemiluminescent enzyme immunoassay; values exceeding 14 μm/l were considered elevated. Results: Mean plasma Hcy was significantly higher in PEXG (16.55 ± 7.23 μm/l) compared with POAG (13.91 ± 3.61 μm/l) and controls (13.12 ± 5.13 μm/l) (p = 0.03 and p = 0.0007 respectively). There were no statistical differences in serum vitamin B12 and folic acid levels among PEXG, POAG and control subjects (p > 0.05). A moderate, although statistically significant, relationship between Hcy and folic acid levels was found in the PEXG group (R(2) = 0.23, p = 0.003). Hcy levels were found not to be related with folic acid or vitamin B12 in either POAG or control subjects. Conclusions: In this study, plasma Hcy is significantly higher in PEXG group than the POAG and control groups. Hyper-Hcy might play a role in the pathogenesis of PEXG. Hyper-Hcy may be an independent factor stressing vasculopathy in addition to pseudoexfoliation, so might be a modifiable risk factor for PEXG.