Glucose-6-phosphate dehydrogenase deficiency in retinal vein occlusion.

PURPOSE

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common human genetic abnormalities, with a high prevalence in Sardinia, Italy. Evidence indicates that G6PD-deficient patients are protected against ischemic heart and cerebrovascular disease. The purpose of this study was to assess the frequency of G6PD deficiency in Sardinian patients with retinal vein occlusion (RVO) and to ascertain whether the deficiency may offer protection against RVO.

METHODS

Erythrocyte G6PD levels were measured in 448 consecutive RVO patients: 194 with central RVO (CRVO) and 254 with branch RVO (BRVO). Age- and sex-matched subjects (n = 896) who were undergoing cataract surgery and had no history of RVO served as the control. Multiple logistic regression models were used to investigate the association between G6PD deficiency and RVO, CRVO, or BRVO.

RESULTS

G6PD deficiency was found in 21 (4.7%) patients with RVO, 7 (3.6%) with CRVO, 14 (5.5%) with BRVO, and 107 (11.9%) control subjects. Differences between cases and controls were statistically significant (P < 0.005). Multiple conditional logistic regression analysis, including as covariates G6PD deficiency, hypertension, diabetes, and hypercholesterolemia, revealed that G6PD deficiency was significantly associated with decreased risk of development of RVO, CRVO, or BRVO. After adjustment for hypertension, diabetes, and hypercholesterolemia, the association between G6PD deficiency and RVO, CRVO, or BRVO remained statistically significant. Similar results were obtained after adjustment for systolic or diastolic blood pressure, plasma glucose, and cholesterol levels. However, when the patients with CRVO or BRVO were categorized by gender, a significant association was found only in the women.

CONCLUSIONS

The frequency of G6PD deficiency in patients with RVO was significantly lower than expected. The results suggest that G6PD-deficient patients have a significantly decreased risk of development of RVO in the Sardinian population.