Oral Vitamin D Supplementation and Clinical Outcomes of Intravitreal Bevacizumab Injection for Macular Edema Secondary to Retinal Vein Occlusions

Purpose: To evaluate the therapeutic response of retinal vein occlusion (RVO) to intravitreal bevacizumab (IVB) with and without concomitant vitamin D supplementation. Method: Seventy eyes of 68 patients with macular edema associated with branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) received three monthly IVB injections. Patients with serum 25-hydroxyvitamin D (25(OH) D) higher than 30 ng/ml were considered as the sufficient group. Cases with serum 25(OH) D levels below 30 ng/ml were randomized into the treatment and control groups. The control group received 50,000 IU of oral vitamin D, weekly for two months. One month after the last IVB injection, best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured and compared with the preinjection values. Results: While 43 eyes (61.4%) of 42 patients had BRVO, 27 eyes (38.6%) of 26 patients had CRVO. In BRVO patients, changes of CMT and BCVA were not significantly different between the sufficient, control, and treatment groups (P = 0.58 and 0.64, respectively). In the CRVO group, CMT reduction in the control group was significantly less than the sufficient and treatment groups (P = 0.048). In addition, improvement of BCVA in the control group was significantly less (P = 0.036) than the sufficient and treatment groups. Conclusion: Oral vitamin D supplement therapy may improve anatomical and functional outcomes in patients with CRVO and vitamin D deficiency.