Association of retinal vein occlusion, homocysteine, and the thrombophilic mutations in a Turkish population: A case-control study

To compare homocysteine and thrombophilic mutations for the methylenetetrahydrofolate reductase (MTHFR) C677T, factor V Leiden, and prothrombin G20210A between retinal vein occlusion (RVO) and healthy controls in a Turkish population.

Forty-nine subjects with RVO were compared for homocysteine status and the MTHFR C677T, prothrombin G20210A, and factor V Leiden mutations with those of 68 healthy controls. Then, the groups were subdivided into two subgroups according to age (less than 50 years old, equal to or more than 50 years old) and were further compared.

Mean plasma level of homocysteine was similar, but the frequency of hyperhomocysteinemia was significantly higher in the RVO group when compared with the control group (22.5% and 8.8%, respectively, p = 0.037). The frequency of all thrombophilic mutations was similar between the groups (p > 0.05). The frequency of all thrombophilic mutations and homocysteine levels was also similar between age subgroups (p > 0.05). Only hyperhomocysteinemia was significantly different between subgroups (p = 0.037); the frequency of hyperhomocysteinemia was significantly different in RVO patients less than 50 years old (22.7%) from that in healthy controls less than 50 years old (11.1%). Two RVO patients (4.1%) with bilateral involvement had MTHFR C677T mutation.

Screening for thrombophilic mutations such as MTHFR C677T, factor V Leiden, and prothrombin G20210A in RVO patients at all ages seems to be unnecessary and not cost-effective. However, thrombophilic disorders should be screened selectively, focusing on young individuals, especially with bilateral involvement, without additional cardiovascular risk factors, or a family history of thrombosis.