12525 Feline Hypersomatotropism In The USA And Canada: Demographics Of 4620 Cats With Presumed Acromegaly

Abstract Disclosure: R.J. Egbert: None. R.C. Fowkes: None. S.J. Niessen: None. B.K. Petroff: None. Spontaneous models of endocrinopathies are powerful tools to understand disease etiology. Endocrine diseases in companion animals are particularly useful to study, as they share their environment with humans and typically present with clinical disease that phenocopies human symptoms. One such disease in domestic cats, hypersomatotropism (HST, feline acromegaly), is a disorder of excessive growth hormone and increased IGF-1 (Insulin like Growth Factor 1), usually caused by hyperplasia or neuroendocrine tumors of the pars distalis of the pituitary gland. This retrospective study used serum IGF-1 results to investigate population characteristics for domestic cats with HST in the United States and Canada. Laboratory records from 1Jan06 to 31Dec22 were reviewed and animals with a circulating IGF-1 hormone concentration of 190 nmol/L (1,450 ng/mL) or greater were presumed to have acromegaly. This review identified 4,620 such cats with a mean age (n=4,351) of 11.2 years (median: 11.2, range: .5-20.3yr) and mean weight (n=2,086) of 6.03 Kg (median: 5.91, range: 2.27-15.0 Kg). Males outnumbered females in the database, which included 3,048 males and 1,181 females. Domestic Short/Medium/Longhair cats were the most prevalent breed (n=3,563; 77%), followed by Maine Coon cats (n=120; 2.6%) and Siamese cats (n=111, 2.4%). Just under half of the animals (n=2,037, 44%) had a history of diabetes mellitus on the submission form. Most submissions were from the US (n=4,347, 94%) with the most hypersomatotropic cats from California (n=841, 18.2%), New York (n=604, 13.1%), Massachusetts (n=402, 8.7%), Colorado (225, 4.9%), and Texas (200, 4.3%). The mean serum IGF-1 concentration of these animals was 358 nmol/mL (median: 345, range 190-761 nmol/mL). For comparison, an age and sex matched control group of 95 animals with residual samples previously submitted for unrelated testing was selected. The mean IGF-1 concentration for the control group was 97 nmol/mL (median: 85, range 0-311 nmol/mL). In summary, HST is diagnosed most frequently in older male cats in urbanized North America, and potentially displays some breed disposition, suggesting both a genetic and environmental component to the disease etiology. Presentation: 6/2/2024