gms | German Medical Science

Homocysteine (Hcy) can induce vascular injury, and alterations of extra-cellular matrix metabolism due to dysregulation of matrix metalloproteinases and their inhibitors, and contributes to neuronal cell death by different mechanisms. Elevated plasma Hcy levels have been found in patients with secondary open-angle glaucoma due to pseudoexfoliation syndrome (PEXG). The present study examined the relationship between vitamin status and plasma Hcy in patients with PEXG.

The study included 51 well nourished patients with PEX glaucoma and 50 controls with concurrent diagnosis of cataract. Total plasma Hcy, vitamin B6, B12 and folate levels were measured in both groups. Exclusion criteria were any commonly known other risk factors for hyperhomocsteinemia and vitamin deficiency The study and control groups were matched by age, gender and concurrent diagnosis of systemic hypertension.

Patients with PEXG showed significantly higher Hcy concentrations (14.3±6.7μmol/l; p=0.016) than control patients (11.53.9±μmol/l). In con-trast, the vitamin B6 and folate levels, but not the vitamin B12 levels, were significantly decreased in PEXG (B6: 10.77±7.23μg/l; p=0.034; folate: 9.745.72 ng/ml; p=0.017; B12: 390±219 pg/ml; p=0.21), when compared with controls (B6: 13.28±8.37 pg/ml; folate: 11.72±5.33 ng/ml; B12: 449±270 pg/ml). Additionally, all three vitamins showed significantly inverse correlation with the Hcy level in PEXG patients (B6: r= - 0.41; p= 0.04; folate: r= - 0.36; p= 0.014; B12: r= -0.32; p= 0.03) but not in controls (B6: r= - 0.22; p= 0.13; folate: r= -0.29; p= 0.052; B12: r= - 0.10; p=0.53).

The moderate hyperhomocysteinemia in patients with PEXG may be caused by decreased levels of vitamin B6 and folate. In well nourished patients, a malabsorption of vitamins due to a manifestation of the general-ized PEX-process in the gastrointestinal tract might be responsible for the lack of vitamins in patients with PEX glaucoma.