Cofactors associated with Sudden Acquired Retinal Degeneration Syndrome: 151 dogs within a reference population.

Abstract

OBJECTIVE: To determine factors associated with sudden acquired retinal degeneration syndrome (SARDS) diagnosed within one referral population. ANIMALS STUDIED: 151 dogs diagnosed with SARDS. PROCEDURES: Breed, age, sex, and body weight were compared between dogs with electroretinogram-confirmed SARDS and dogs presented to the UC Davis Veterinary Medical Teaching Hospital (UCD-VMTH) from 1991 to 2014. RESULTS: SARDS was diagnosed in 151 dogs, representing 1.3% of dogs presented to the UCD-VMTH for ophthalmic disease. Although dogs of 36 breeds were affected, the Dachshund (n&#xa0;=&#xa0;31, 21%), Schnauzer (16, 11%), Pug (11, 7%), and Brittany (5, 3%) were significantly overrepresented, and the Labrador Retriever (3, 2%) was significantly underrepresented vs. the reference population (P&#xa0;<&#xa0;0.001). Median (range) age and body weight of affected vs. reference dogs were 8.9 (3-20) vs. 6.8 (0.1-26)&#xa0;years and 12.4 (2.8-52.7) vs. 22.3 (0.1-60)&#xa0;kg, respectively. Dogs 6-10&#xa0;years of age and between 10-20&#xa0;kg in body weight were significantly overrepresented in the SARDS population, while dogs <6&#xa0;years of age were significantly underrepresented (P&#xa0;<&#xa0;0.01). Spayed females (59% of affected dogs) were significantly overrepresented compared to the reference population, whereas intact females (1% of affected dogs) were significantly underrepresented. CONCLUSIONS: Consistent with previous studies, smaller, middle-aged, spayed female dogs may be at increased risk of developing SARDS. Unlike previous studies, this is the first study comparing a variety of SARDS-affected breeds to a reference population. Potentially increased risk of SARDS in several breeds, particularly Dachshunds, suggests a familial factor that warrants further investigation using genetic techniques.