The largest study to date to estimate the prevalence and risk factors for Cushing’s syndrome in dogs attending primary-care practice in the UK has found several novel breed associations for the disease. The study, published in the latest issue of the Journal of Small Animal Practice (JSAP), identified that the Border terrier, the Lhasa apso and Staffordshire bull terrier have increased odds of Cushing’s syndrome compared with crossbreed dogs in the UK primary-practice population.
The study “Frequency and risk factors for naturally occurring Cushing’s syndrome in dogs attending UK primary-care practices”, identified dogs with Cushing’s syndrome from the electronic patient records of practices participating in the UK VetCompass programme during 2016. Both pre-existing and incident cases of Cushing’s syndrome during 2016 were included to estimate the one-year period prevalence.
Available demographic data for study dogs included date of birth, sex, neuter status, breed and mean lifetime bodyweight above 18 months. Multivariable binary logistic regression modelling was used to assess the associations between risk factors and Cushing’s syndrome.
Dr Imogen Schofield, corresponding author for the paper, said: “A total of 1,527 Cushing’s syndrome cases were identified in this study, from a population of 905,544 dogs in 2016. The estimated one-year period prevalence for Cushing’s syndrome in dogs was 0.17 percent (95 percent confidence interval 0.05 to 0.07).”
“The findings of this study provide evidence from primary-care clinical records on the epidemiology of Cushing’s syndrome which can help primary-care veterinarians during diagnosis.
“Seven breeds were associated with increased odds of Cushing’s syndrome; the Bichon frise (OR=6.17, 95 percent CI 4.22 to 9.00), Border terrier (5.40, 95 percent CI 3.66 to 7.97), Miniature schnauzer (3.05, 95 percent CI 1.67 to 5.57), Lhasa apso (2.52, 95 percent CI 1.49 to 4.28), Yorkshire terrier (1.82, 95 percent CI 1.23 to 2.70), Staffordshire bull terrier (1.52, 95 percent CI 1.08 to 2.13) and Jack Russell terrier (1.50, 95 percent CI 1.07 to 2.08).
“Four breeds were at decreased odds of Cushing’s syndrome: the Golden retriever (0.24, 95 percent CI 0.06 to 0.98), Labrador retriever (0.3, 95 percent CI 0.17 to 0.54), Border collie (0.32, 95 percent CI 0.13 to 0.78) and Cocker spaniel (0.44, 95 percent CI 0.21 to 0.90), which could help vets in practice lower their index of suspicion for Cushing’s syndrome for these breeds.
“Dogs with a bodyweight higher than their breed-sex mean had 1.44 times the odds of Cushing’s syndrome than those within their breed mean (95 percent CI 1.17 to 1.78), suggesting either over-weight dogs or larger examples of the breed are at increased risk of this condition or that dogs with Cushing’s syndrome gain weight.”
Nicola Di Girolamo, editor of JSAP, concluded: “When we look at risk factor analysis in previous studies, the generalisability of their findings to the general population of dogs in the UK have typically been limited due to studying dogs from referral populations or due to a lack of multivariable analysis.
“The findings of this study help to address that knowledge gap, supporting some of the risk factors previously reported, and by identifying novel associations, such as that in the Border terrier.
“Awareness of breeds with high or low risk could help to enhance the index of suspicion for veterinary surgeons working in primary-care practice where Cushing’s syndrome is predominantly diagnosed and managed.”
The full article can be found in the April issue of the Journal of Small Animal Practice and can be read online.
The Journal of Small Animal Practice is published monthly and access to articles is free for BSAVA members. For information on how to become a BSAVA member visit the membership page on the BSAVA website.
