Thrombophilic mutations as risk factor for retinal vein occlusion: a case-control study

Abstract

Background: Retinal vein occlusion (RVO) is the second most common retinal vein disease and an important cause of blindness and visual morbidity. Many conditions are associated with RVO but the real role of the thrombophilic mutations is still unclear.

Aim: To evaluate the potential role of thrombophilic mutations in RVO.

Methods: We have evaluated 113 patients with RVO and compared with 104 volunteer controls. The controls were all healthy blood donors without previous venous thromboembolism episode or arterial thromboembolism episode. All patients were tested for 5 gene variants (here all named as mutations): factor V (FV) Leiden (G1691A), factor II (FII; G20210A), 5,1-methylenetetra-hydrofolate reductase (MTHFR; C677T), plasminogen activator inhibitor 1 (PAI-1; 4G/5G), and angiotensin-converting enzyme (ACE; Del/Ins). Statistical analysis were performed by the 2-tailed chi-square test.

Results: Statistical test showed that TT homozygous patients of the MTHFR C677T mutation (P = .017) and heterozygous GA patients of the FII G20210A mutation (P = .018) were significantly higher than that in controls. For FV Leiden, even if the values were higher in patients than in controls, P value was not statistically significant. Conversely, for the ACE (Ins/Del) and PAI-1 (4G/5G) mutations, no difference was observed among genotypes of patients with RVO and control participants.

Conclusions: In our study, the FII G20210A and the MTHFR C677T mutations resulted significantly higher in patients than in controls; in contrast, thrombophilic mutation of FV, ACE, and PAI-1 genes was not statistically correlated with RVO. In spite of having found an association between some thrombophilic mutations and RVO, more studies with a major number of patients are necessary to determine the final role of these gene variants.

Keywords: genetic mutations; retinal vein occlusion; thromboembolism; thrombophilia.