Effect of oral antioxidants on the progression of canine senile cataracts: a retrospective study

Background: Cataracts are the leading cause of impaired vision or blindness in dogs. There are many antioxidants that can prevent cataract progression, but whether they are clinically effective in dogs has not been established. Objectives: To analyze the delaying or preventing effect of oral antioxidants on canine senile cataracts through retrospective analysis. Methods: Medical records of dogs from January 1, 2015 to July 10, 2020 were reviewed. Dogs that were 8 yr of age or older with senile cataracts were included in this study. The dogs were divided into two treatment groups (dogs administered with Ocu-GLO supplement and dogs administered with Meni-One Eye R/C supplement) and a control group (dogs that were not administered any supplement). Dogs with incipient and immature cataracts were included in this study. Altogether, 112 dogs (156 eyes) with incipient cataracts and 60 dogs (77 eyes) with immature cataracts were included. The period of time that cataracts progressed from incipient to immature, and from immature to mature was recorded for each dog. Results: There was no significant delaying effect on the progression of incipient cataracts. However, both Ocu-GLO (hazard ratio = 0.265, p = 0.026) and Meni-One (hazard ratio = 0.246, p = 0.005) significantly delayed the progression of immature cataracts compared to the control group. Conclusions: Although there was no significant delaying effect of oral antioxidants on incipient cataract progression, antioxidants could be used to delay the progression of senile immature cataract.