Plasma homocysteine, vitamin B12 and folate levels in age-related macular degeneration.

Department of Ophthalmology, Hacettepe University Hospital, 06100, Sihhiye, Ankara, Turkey.
Albrecht von Graæes Archiv für Ophthalmologie (Impact Factor: 2.33). 06/2006; 244(5):565-9. DOI: 10.1007/s00417-005-0108-2
Source: PubMed

ABSTRACT The purpose of this study was to investigate the association of age-related macular degeneration (AMD) with plasma homocysteine, vitamin B12, and folate levels.
Sixty patients diagnosed with AMD at our clinic between March 2004 and September 2004 were assessed in a prospective cross-sectional study. Plasma homocysteine, vitamin B12, and folate levels taken after 8 h of fasting from 30 patients with exudative AMD and 30 patients with dry AMD were compared with the results of 30 age- and sex-matched healthy participants.
Patients with both exudative and dry types of AMD had significantly higher plasma homocysteine levels (mean 14.19+/-3.11 micromol/l; 13.07+/-2.90 micromol/l respectively) compared with the controls (mean 10.79+/-2.56 micromol/l; (p=0.000 and p=0.008 respectively). Homocysteine levels were higher in the exudative AMD group compared with the dry AMD group, but the difference was not statistically significant (p=0.290). Plasma vitamin B12 levels were found to be significantly lower in the exudative AMD group (289.14+/-113.44 pg/l) compared with the controls (436.17+/-204.12 pg/l) and dry AMD group (443.47+/-190.83 pg/l; (p=0.000). Plasma folate levels were comparable among groups (p=0.106).
This study suggests an association between elevated plasma homocysteine and AMD regardless of the subtype. Further controlled prospective studies are needed to investigate the possible role of homocysteine in AMD and the effect of vitamin B12 and folate supplementation in this process.

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    ABSTRACT: To evaluate levels of homocysteine, asymmetric dimethylarginine (ADMA), and nitric oxide (NO), as well as activity of endothelial NO synthase (eNOS), in patients with age-related macular degeneration (AMD).
    Clinical ophthalmology (Auckland, N.Z.) 01/2014; 8:1573-8. DOI:10.2147/OPTH.S66160
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    ABSTRACT: Abstract Purpose/Aim: To compare the plasma levels of homocysteine and asymmetrical dimethyl-l-arginine (ADMA) and the degree of whole blood DNA methylation in patients with early and neovascular age-related macular degeneration (AMD) and in controls without maculopathy of any sort. Materials and methods: This observational case-control pilot study included 39 early AMD patients, 27 neovascular AMD patients and 132 sex- and age-matched controls without maculopathy. Plasma homocysteine and ADMA concentrations and the degree of whole blood DNA methylation were measured. Quantitative variables were compared by Student's t-test or Mann-Whitney test. Logistic regression models were used to investigate the significance of the association between early or wet AMD and some variables. Results: There were no significant differences in mean plasma homocysteine and ADMA concentrations and in the degree of whole blood DNA methylation between patients with early or neovascular AMD and their controls. Similarly, logistic regression analysis disclosed that plasma homocysteine and ADMA levels were not associated with an increased risk for early or neovascular AMD. Conclusions: We failed to demonstrate an association between early or neovascular AMD and increased plasma homocysteine and/or ADMA. Results also suggest that the degree of whole blood DNA methylation is not a marker of AMD.
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    Turkish Journal of Electrical Engineering and Computer Sciences 11/2013; 21:2062 – 2078. DOI:10.3906/elk-1111-21 · 0.57 Impact Factor


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