Hyperhomocysteinemia and the MTHFR C677T mutation in central retinal vein occlusion

Abstract

ABSTRACT.Background: Hyperhomocysteinemia is a factor that predisposes to thrombosis, and the C677T mutation in methylene-tetrahydrofolate reductase (MTHFR) is known to give increased plasma homocysteine. We wanted to investigate if these factors were overrepresented in a group of patients with central retinal vein occlusion. Methods: 116 patients with a history of central retinal vein occlusion were examined for the presence of hyperhomocysteinemia and the MTHFR C677T mutation. Results: Compared to the control groups, there was no significant increase, neither in plasma homocysteine nor in the frequency of the MTHFR C677T mutation in the patients. Even when we looked selectively at the young patients, age less than 50 years, no difference could be detected. Conclusion: It seems that neither hyperhomocysteinemia nor the MTHFR C677T mutation is an important risk factor for the aetiology of central retinal vein occlusion.

Hyperhomocysteinemia and low plasma folate as risk factors for central retinal vein occlusion: a case–control study in a Chinese population

“…In a logistic regression analysis, a 1 μmol/l increase of plasma homocysteine level was associated with an odds ratio of 1.368. Our results are similar to those of the study conducted by Weger et al [16], but differ from those of Hayreh et al [8] and Larsson et al [11]. The discrepancies may be due to two reasons: First, the study populations were different.…”

Hyperhomocysteinemia: A Risk Factor for Retinal Vein Occlusion

“…The results of these studies all indicate that hyperhomocysteinemia is a risk factor for RVO, similar to the findings of this study. On the other hand, there are reports in the literature with contradictory findings in which no significant association between hyperhomocysteinemia and RVO was found [13, 14, 15]. Thus, the role of hyperhomocysteinemia in RVO is debatable in view of the contradictory results.…”

“…One can speculate that, although plasma folate levels were comparable between RVO cases and controls, they were not sufficient for patients with RVO, possibly because they had a genetically variant MTHFR enzyme (which, in fact, was not investigated in this study) that resulted in elevated plasma tHcy levels. On the other hand, studies investigating the role of the MTHFR variant in the etiology of RVO have also resulted in conflicting outcomes [10, 11, 13, 20]. The prevalence of MTHFR mutation is known to change considerably according to the geographic area; hence, results of these studies may depict the role of different genetic backgrounds [11].…”

Central Retinal Vein Occlusion Associated with Hyperhomocysteinemia in a Patient with Heterozygous for the Methylenetetrahydrofolate Reductase C677T Mutation: Case Report

“…13 In contrast, Larsson et al stated that neither hyperhomocysteinemia nor the MTHFR gene mutation are important risk factors for retinal vein occlusion. 17 Di Crecchio et al suggested that hyperhomocysteinemia, along with the MTHFR gene mutation, were not a prime reason, but could be a determinant of atherosclerosis. 18 These studies show that the relationship between the MTHFR gene mutation and thromboembolic events is still uncertain.…”