Eye drops slow cataracts in dogs with diabetes

Abstract

OBJECTIVE: To determine whether topical administration of the aldose reductase inhibitor Kinostat™ can ameliorate the onset or progression of cataracts in dogs with naturally occurring diabetes mellitus (DM). MATERIALS AND METHODS: A randomized, prospective, double-masked placebo control pilot study was conducted with 40 dogs newly diagnosed with DM with no or minimal lens changes. Twenty-eight dogs received Kinostat™ and 12 dogs received placebo. PROCEDURES: Owners administered the agent into both eyes three times daily for 1 year and compliance was monitored with log sheets. Complete ophthalmic examinations were performed on dilated eyes at the time of enrollment and 1, 2, 3, 6, and 12 months into treatment. Cataract severity was assessed on a scale of 0-3. At 12 months, full bloodwork, including HbA1C and blood Kinostat™ levels were performed. RESULTS: After 12 months of treatment, the cataract score in the placebo group significantly increased with seven dogs (14 eyes) developing mature cataracts, two dogs (4 eyes) developing cortical opacities, and one dog (2 eyes) developing equatorial vacuoles with mild punctate cortical opacities. In contrast, the cataract score in the Kinostat™ treated dogs was significantly less with seven developing anterior equatorial vacuoles, two developing incipient anterior cortical cataracts, and four developing mature cataracts. In fact, the cataract scores of the Kinostat™ group at 12 months did not significantly increase from the score at the time of enrollment. The HbA1C values between the two groups after 12 months of treatment were similar, and no blood levels of Kinostat™ were found in any enrolled dog. CONCLUSION: The onset and/or progression of cataracts in dogs with DM can be significantly delayed by topical administration of Kinostat™.