DOGS TREATED WITH TRILOSTANE IN FIRST OPINION PRACTICE USING A PROTOCOL FORTIGHT CONTROL OF HYPERCORTISOLISM: SURVIVAL TIMES

SF Foster,

1 JM Morton,2LM Fleeman,3 KFA Langner,4 JA Braddock.1

1. Vetnos@cs, 60 Waterloo Rd, Macquarie Park NSW 2113, Australia; 2. Jemora Pty Ltd, PO Box 5010, East Geelong Vic 3219, Australia; 3. Animal Diabetes Australia, 5 Hood St, Collingwood VIC 3066, Australia; 4. Western Australian Veterinary Emergency and Specialty, 1/640 Beeliar Drive, Success WA 6164, Australia

Background: Conservative control of hypercortisolism is implemented to limit clinical hypocortisolism. Hypothesis: Dogs with tight control of hypercortisolism, defined by adrenocorticotropic hormone (ACTH)-stimulated cortisol concentrations <70 nmol/L (Advia Centaur) on tests 4-6 h after trilostane in first opinion practice have long survival times.

Methods: Dogs with tight control ≥ 12 months were identified between August 2017 and February 2019. The dogs’ veterinarians were contacted for survival data in March and April 2022. One-, 2-, and 3-year survival percentages from the end of the dogs’ first 12-month period of tight control were calculated using the Kaplan-Meier survival function. For comparison, crudely equivalent measures for dogs treated with trilostane under other protocols in referral and general practice were also calculated from published papers.

Results: There were 41 periods of tight control in 40 dogs with median age at the first monitoring test being 10 years. The mean interval from diagnosis to the end of the first 12 months of tight control was 588 days. Median survival times from the end of the first 12 months of control for dogs aged <11 years, 11 to <12.5 years, and ≥12.5 years, respectively, were 1,519, 1,260, and 525 days. One-, 2-, and 3-year survival percentages from the end of 12 months of tight control were 95%, 65%, and 37%, respectively. Survival times were beler or comparable to those from previous studies.

Conclusions: Tight control of hypercortisolism in first opinion practice, assessed by ACTH simulation tests 4-6 h after trilostane, is associated with long-term survival rates.